ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Photosynthesis
  • Springer  (51)
  • American Association for the Advancement of Science (AAAS)
  • American Association of Petroleum Geologists (AAPG)
  • American Geophysical Union
  • Elsevier
  • Periodicals Archive Online (PAO)
  • 1975-1979  (51)
Collection
Keywords
Publisher
  • Springer  (51)
  • American Association for the Advancement of Science (AAAS)
  • American Association of Petroleum Geologists (AAPG)
  • American Geophysical Union
  • Elsevier
    • +
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    A proposal concerning the origin of life on the planet earth (1979)
    Springer
    Journal of molecular evolution 13 (1979), S. 95-101 
    Details
    ISSN: 1432-1432
    Keywords: Oparin Ocean ; Origin of Life ; Evolution ; Runaway greenhouse ; Photosynthesis ; Methanogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The widely accepted Oparin thesis for the origin and early evolution of life seems sufficiently far from the true state of affairs as to be considered incorrect. It is proposed that life on earth actually arose in the planet's atmosphere, however an atmosphere very different from the present one. Because of an extremely warm surface, the early earth may have possessed no liquid surface water, its water being partitioned between a molten crust and a fairly dense atmosphere. Early preliving systems are taken to arise in the droplet phase in such an atmosphere. The early earth, which resembled Venus then and to some extent now, underwent a transition to its present condition largely as a result of the evolution of methanogenic metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01732865
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Effect of carbon dioxide and temperature on photosynthetic CO2 uptake and photorespiratory CO2 evolution in sunflower leaves (1979)
    Springer
    Planta 145 (1979), S. 219-223 
    Details
    ISSN: 1432-2048
    Keywords: C3-plants ; CO2 and photorespiration ; Helianthus ; Photorespiration ; Photosynthesis ; Temperature and photorespiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using an open gas-exchange system, apparent photosynthesis, true photosynthesis (TPS), photorespiration (PR) and dark respiration of sunflower (Helianthus annuus L.) leaves were determined at three temperatures and between 50 and 400 μl/l external CO2. The ratio of PR/TPS and the solubility ratio of O2/CO2 in the intercellular spaces both decreased with increasing CO2. The rate of PR was not affected by the CO2 concentration in the leaves and was independent of the solubility ratio of oxygen and CO2 in the leaf cell. At photosynthesis-limiting concentrations of CO2, the ratio of PR/TPS significantly increased from 18 to 30°C and the rate of PR increased from 4.3 mg CO2 dm-2 h-1 at 18°C to 8.6 mg CO2 dm-2 h-1 at 30°C. The specific activity of photorespired CO2 was CO2-dependent but temperature-independent, and the carbon traversing the glycolate pathway appeared to be derived both from recently fixed assimilate and from older reserve materials. It is concluded that PR as a percentage of TPS is affected by the concentrations of O2 and CO2 around the photosynthesizing cells, but the rate of PR may also be controlled by other factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00454444
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Analysis and characterization of DCMU-resistant Euglena gracilis (1979)
    Springer
    Planta 145 (1979), S. 259-267 
    Details
    ISSN: 1432-2048
    Keywords: DCMU-resistance ; Euglena ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Dark-grown, DCMU-adapted Euglena gracilis Z (ZR) are able to undergo light-induced chloroplast development in the presence or absence of DCMU. The differentiated chloroplasts are photosynthetically active and are resistant not only to DCMU, but also to an analog, o-phenanthrolene. When DCMU overdoses are added to ZR cells or to chloroplasts isolated from these cells, photosynthesis is partially inhibited. A brief period of darkness removes this inhibition. This recovery phenomenon is related to DCMU resistance, since it is not exhibited by non-resistant control cells. The chloroplast protein synthesis apparatus is not involved in DCMU resistance. Rather, this phenomenon is apparently related to new characteristics of thylakoids. It is shown that photosynthetic recovery by ZR cells depends on the accessibility and fluid properties of membranes. The analysis of fluorescence induction kinetics shows that changes in the environmental conformation of photosystem II units occur during recovery.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00454450
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Photomovement of the red alga Porphyridium cruentum (Ag.) naegeli I. Photokinesis (1979)
    Springer
    Archives of microbiology 122 (1979), S. 207-212 
    Details
    ISSN: 1432-072X
    Keywords: Photokinesis ; Red algae ; Porphyridium cruentum ; Action spectrum ; Photosynthesis ; Inhibitors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Photokinesis of the red alga Porphyridium cruentum was studied with the aid of a population method. Because of the slow spreading velocity (0.35 μm/min) the duration of the experiments was 7 days in general. According to the white light illuminance-response curve the zero threshold of photokinesis lies below 10 lx and the optimum around 10,000 lx. With further increasing illuminance the photokinetic effect decreases, reaching zero at about 100,000 lx. The action spectrum indicates that the photokinetically active radiation is absorbed by photosynthetic pigments, namely the biliproteins B-phycoerythrin, R-phycocyanin and allo-phycocyanin, as well as by chlorophyl a, although the photokinetic effect of blue light is relatively low. From the action spectrum and the results of inhibitor experiments with DCMU, DBMIB and DSPD it is concluded that the photokinetic effect is due to an additional ATP supply from non-cyclic and/or pseudo-cyclic photophosphorylation to the motor apparatus.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00411362
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Isolation of cyanobacteria from the aquatic fern, Azolla (1979)
    Springer
    Archives of microbiology 120 (1979), S. 161-165 
    Details
    ISSN: 1432-072X
    Keywords: Azolla ; Cyanobacteria ; Blue-green algae ; Nitrogen fixation ; Symbiont ; Photoheterotroph ; Algal isolation ; Photosynthesis ; Plant metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A procedure has been developed to isolate cyanobacteria from the aquatic fern Azolla. The method is based upon recovery of cyanobacterial “bundles” from digests of plants and use of this material as a massive inoculum for nitrogen-free media, followed by prolonged incubation in light. The procedure appears to select for those cells capable of growth in vitro. Isolated cyanobacteria were found to resemble Anabaena sp. morphologically but were capable of heterotrophic growth and had high nitrogenase activity when grown on fructose in the dark.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00409103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Hydrogen formation by cyanobacteria cultures selected for nitrogen fixation (1979)
    Springer
    Archives of microbiology 123 (1979), S. 227-232 
    Details
    ISSN: 1432-072X
    Keywords: Hydrogen production ; Nitrogen fixation ; Photosynthesis ; Cyanobacteria ; Enrichment cultures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Seventy-one cyanobacteria containing cultures were enriched from various soil and water locations either under aerobic and/or anaerobic conditions on agar medium selective for nitrogen fixation. Kept under argon containing 1% CO2 for 24 and 48 h most of these cultures evolved hydrogen at very variable rates up to 116 μl per mg chlorophyll and hour as a mean value over a time period of 24h. Several samples evolved hydrogen more efficiently compared with known hydrogen producing pure strains from culture collections. Thirty-one of the investigated cultures showed a hydrogen formation higher than 10 μl per mg chlorophyll and hour measured over 24 or 48 h. Among these all the morphological forms of cyanobacteria i.e. unicellular and filamentous with or without heterocysts are found. Hence, selecting for nitrogen fixing cyanobacteria seems to be a practical method to find efficient hydrogen producers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00406654
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The structure of cyanobacterial phycobilisomes: a model (1979)
    Springer
    Archives of microbiology 123 (1979), S. 113-127 
    Details
    ISSN: 1432-072X
    Keywords: Phycobilisomes ; Phycobiliproteins ; Cyanobacteria ; Chromatic adaptation ; Fine structure ; Photosynthesis ; Protein assembly
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phycobilisomes, supramolecular complexes of water-soluble accessory pigments, serve as the major light-harvesting antennae in cyanobacteria and red algae. Regular arrays of these organelles are found on the surface of the thylakoid membranes of these organisms. In the present study, the hemi-discoidal phycobilisomes of several species of cyanobacteria were examined in thin sections of cells and by negative staining after isolation and fixation. Their fundamental structures were found to be the same. Isolated phycobilisomes possessed a triangular core assembled from three stacks of disc-shaped subunits. Each stack contained two discs which were ∼12 nm in diameter and ∼6–7 nm thick. Each of these discs was probably subdivided into halves ∼3–3.5 nm thick. Radiating from each of two sides of the triangular core were three rods ∼12 nm in diameter. Each rod consisted of stacks of 2 to 6 disc-shaped subunits ∼6 nm thick. These discs were subdivided into halves ∼3 nm thick. The average number of discs of ∼6 nm thickness forming the peripheral rods varied among the strains studied. For certain chromatically adapting strains, the average rod length was dependent upon the wavelength of light to which cells were exposed during growth. Analyses of phycobilisomes by spectroscopic techniques, polyacrylamide gel electrophoresis, and electron microscopy were compared. These analyses suggested that the triangular core was composed of allophycocyanin and that the peripheral rods contained phycocyanin and phycoerythrin (when present). A detailed model of the hemi-discoidal phycobilisome is proposed. This model can account for many aspects of phycobiliprotein assembly and energy transfer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00446810
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Parameter identification of the calvin photosynthesis cycle (1979)
    Springer
    Journal of mathematical biology 7 (1979), S. 99-116 
    Details
    ISSN: 1432-1416
    Keywords: Parameter identification ; Error sensitivity analysis ; Calvin cycle ; Photosynthesis ; Non-linear optimization ; Stiff systems of differential equations ; Chemical biodynamics ; Biochemical kinetics ; Mathematical models ; Numerical techniques
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Summary This article is concerned with the determination of kinetic parameters of the Calvin photosynthesis cycle which is described by seventeen nonlinear ordinary differential equations. It is shown that the task requires dynamic data for several sets of initial conditions. The numerical technique is based upon an algorithm for non-linear optimization and Gear's numerical integration scheme for stiff systems of differential equations. The sensitivity of the parameters to noise in the data is tested with a method adapted from Rosenbrook and Storey. A preliminary set of parameters has been obtained from a preliminary set of experimental data. The numerical methods are then tested with synthetic data derived from these parameters. The mathematical model and the results obtained in the simulation are used as an aid in designing new experiments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00276924
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Auslösung der circadianen Photosynthese-Rhythmik beiAcetabularia durch Blaulicht (1979)
    Springer
    Protoplasma 99 (1979), S. 341-346 
    Details
    ISSN: 1615-6102
    Keywords: Acetabularia ; Blue light ; Circadian rhythm ; Photosynthesis ; “Zeitgeber”
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Additional irradiation with blue light of low intensity ofAcetabularia mediterranea cells, pretreated by prolonged irradiation with red, induces an increase of photosynthetic activity. This induction is accompanied by the appearance of rhythmic changes of the O2 production. Maxima are found about 6, 30, 54, 78, ... hours after the onset of blue light irradiation. Thus blue light not only induces an increase of the rate of photosynthesis but also acts as a “Zeitgeber” for the circadian rhythm of photosynthesis inAcetabularia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01275806
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Studies onSargassum (1979)
    Springer
    Protoplasma 99 (1979), S. 247-261 
    Details
    ISSN: 1615-6102
    Keywords: Phaeophyta ; Photosynthesis ; Respiration ; Stereology ; Structure-function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Cytological comparisons of homologous tissues in blades and stipes by stereological analysis have shown differences exist between blade and stipe organs inSargassum. Based on measurements of total thylakoid and cristae membrane surface areas in these organs blades were found to contain 61% more thylakoid membrane surface and 65% more cristae membrane than stipes on a per unit volume basis. Assuming photosynthesis and respiration are directly related to the surface area of the internal membranes in the respective organelles it is possible to predict that blades will have a 61% greater photosynthetic and a 65% greater respiratory potential. Photosynthetic and respiratory rates for blades and stipes were determined manometrically and show a 62% greater photosynthetic and 59% greater respiratory rates for the blade tissues agreeing very well with predicted values. Present evidence indicates that photosynthetic and respiratory rate differences observed in the blades and stipes inSargassum are the result of increased membrane surface areas in the larger cells of the tissues which make up the blade. The basic cell structure,i.e., the percent volume of cell cytoplasm occupied by each organelle, is similar in homologous tissues of both organs regardless of cell size. Therefore physiological differences between the two organs are primarily due to changes in cell size and not in basic cell construction. This provides an interesting mechanism for producing physiological differences without changing basic cell structure in the organs of this plant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01275799
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Effects of salinity, N-nutrition and humidity on photosynthesis and protein metabolism ofChloris gayana Kunth (1979)
    Springer
    Plant and soil 53 (1979), S. 477-486 
    Details
    ISSN: 1573-5036
    Keywords: Chloris ; Humidity ; Nitrogen ; Nutrition ; Photosynthesis ; Rhodes grass ; Salinity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Under high atmospheric humidity, Rhodes grass plants responded favourably to an increase in nitrate fertilization. Under low atmospheric humidity an optimum point was reached at lower N-treatment. Plants' growth was improved by a salinity treatment of up to 100 mM, at high atmospheric humidity. A higher salt concentration cancelled the favourable effect of added nitrate. The rise in yield which follows salt or nitrate treatments is apparently combined with an increase in activity of the key photosynthetic enzymes, Phosphoenol pyruvate carboxylase and Ribulose biphosphate carboxylase. A similar rise in activity is seen in nitrate reductase, a key enzyme in nitrogen metabolism. Evidently, all three enzymatic systems are not damaged in high salt treatments, and the potential photosynthetic capacity remained practically uneffected in all treatments. As no correlation could be found between transpiration and growth curves, it is assumed that the supply of CO2 is also unhampered. Thus, the major negative effect of salinity, seems to be on protein synthesis, which eventually leads to disturbed growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02140719
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Studies of soil moisture stress in barley (Hordeum vulgare L.) (1979)
    Springer
    Plant and soil 52 (1979), S. 581-584 
    Details
    ISSN: 1573-5036
    Keywords: Barley ; Photosynthesis ; Protein ; Respiration ; Soil moisture stress ; Water use efficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The objective was to find the optimum range of water contents for inducing better growth, physiological efficiency and yield potential of barley plants (Hordeum vulgare L. var. K18). A pot culture experiment was conducted in the Division of Crop Physiology and Biochemistry Kanpur-2. The plants were subjected to various soil moisture stresses,i.e., 0.15, 0.30, 0.45, 0.60 and 0.75 atm tension throughout the crop growth period measured by irrometers. Plants maintained at 0.45 soil moisture tension required 19.07 litre of water and had the best water use efficiency (1765 mg dm/litre of water) which favourably influenced the leaf water balance (85.9%), plant growth as measured by plant height (85.4 cm) and tiller production (35.6) per hill, photosynthetic efficiency (2.185 mg CO2/g dm/h), grain number (722) and grain yield (33.7 g) per hill while plants irrigated at a tension greater than 0.45 SMT did not develop as well. However, protein and gluten percentage increased gradually with the subsequent increase in soil moisture tension. On the other hand respiration rate (2.090 mg CO2/g dm/hr) and leaf area (4375 cm2) were recorded to be the highest at 0.60 and 0.30 atm SMT respectively. Thus it is suggested that for reaping high harvest of barley crop, the physiological need of water (19.07 litre) in total of plant life should be made available through scheduled irrigation based on maintenance of plant at 0.45 SMT from seeding to maturity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02277954
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Photosynthetic carbon fixation in iron-chlorotic and recovered green sugarcane leaves (1979)
    Springer
    Plant and soil 53 (1979), S. 505-511 
    Details
    ISSN: 1573-5036
    Keywords: Chlorophylls ; Ferrous sulphate ; Inactive iron ; Iron chlorosis ; Malate synthesis ; Photosynthesis ; Sucrose metabolism ; Sugarcane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Sugarcane var. Co 740 is grown in various parts of Maharashtra (India) and is susceptible to chlorosis due to physiological non-utilization of iron. The physiological disorder is seen over a large area and it results in poor yield. Low sucrose yield can be recovered by foliar sprays of ferrous sulphate. The nonchlorotic and chlorotic leaves were used for the photosynthetic studies. The leaves after ferrous sulphate treatment show an increase in total chlorophyll contents and at the same time show an improved chlorophylla to chlorophyllb ratio which is affected in the chlorotic ones. The recovered green leaves have higher uptake of nitrogen, phosphorus, potassium and iron.14CO2 fixation studies for short- and long-term experiments reveal that recovered green leaves can synthesize malate more efficiently and also utilize it for sucrose synthesis more rapidly than in the chlorotic ones. On the contrary more amino acids, reducing sugars and sugar phosphates are synthesized in the chlorotic leaves. There is also an accumulation of citrate, glutamate, and tartrate in the chlorotic leaves. Our results indicate that sucrose synthesis is disturbed in the chlorotic leaves and can be corected byfolia: sprays of ferrous sulphate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02140721
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    A model for the evolution of photosynthetic oxygen (1978)
    Springer
    Pure and applied geophysics 116 (1978), S. 234-238 
    Details
    ISSN: 1420-9136
    Keywords: Atmospheric evolution ; 13C ; Photosynthesis ; Sedimentary mass
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01636881
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    The early history of oxygen and ozone in the atmosphere (1978)
    Springer
    Pure and applied geophysics 117 (1978), S. 498-512 
    Details
    ISSN: 1420-9136
    Keywords: History of atmosphere ; Oxygen ; Ozone ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract There may have been three stages in the growth of oxygen in the terrestrial atmosphere. Prior to the origin of photosynthesis the only source of oxygen was photolysis of water vapor followed by escape of hydrogen to space. The rate of this process was probably less than the rate of release of reduced gases (principally hydrogen) from volcanoes, so the oxygen partial pressure was held to negligibly low values by photochemical reactions with an excess of hydrogen. The photosynthetic source of oxygen was probably in operation as long ago as 3.8 billion years. It released oxygen to the ocean. Presumably most of this oxygen was destroyed in the ocean as long as its rate of supply was less than the rate of supply of readily oxidizable material (principally Fe2+) provided by the weathering of rocks. This phase appears to have lasted until about 2 billion years ago, during which period most banded iron formations were deposited. During this period the production of oxygen by algae was limited by competition with photosynthetic bacteria, which preempted the supply of nutrient phosphorus as long as reduced chemicals were available in the environment. Once the photosynthetic oxygen source exceeded the rate of supply of reduced minerals exposed by erosion and weathering, the accumulation of oxygen in the ocean and atmosphere could be controlled only by reaction of oxygen with reduced organic material. This is the stabilization mechanism that operates today. It seems unlikely that oxygen could be consumed at a significant rate by this process until oxygen levels sufficiently high to support respiration had been achieved. I therefore suggest that atmospheric oxygen rose rapidly from essentially zero to approximately its present value (within a factor of 10) when the photosynthetic source of oxygen rose above the weathering source of reduced minerals, probably about 2 billion years ago. The ozone layer and the ultraviolet screen were absent prior to this time and essentially fully developed after this time.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00876630
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    The biota as ancient and modern modulator of the Earth's atmosphere (1978)
    Springer
    Pure and applied geophysics 116 (1978), S. 239-243 
    Details
    ISSN: 1420-9136
    Keywords: Gaia ; Paleoatmospheres ; Atmospheric oxygen ; Photosynthesis ; Microbial gas exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The composition of the Earth's atmosphere is thought to have been highly modified by surface microbiotas and modulated around quantities of gases optimized for growth of these microbiotas. Three diagrams are presented: The first shows a probable order of appearance of major metabolic pathways in microbes that interact with sediment and atmosphere. It is based on evolutionary considerations and was devised independently of the fossil record. The second diagram shows the qualitative emissions and removals of atmospheric gases by obligately anaerobic organisms; it approximates those processes thought to have dominated the Earth's atmosphere in Archean times. The third diagrams gaseous emissions and removals by the major groups of organisms, including oxygen-releasing and utilizing forms. Biological gas exchange processes thought to have dominated the atmosphere since the Proterozoic are thus represented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01636882
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Long-term global sea surface temperature fluctuations and their possible influence on atmospheric CO2 concentrations (1978)
    Springer
    Pure and applied geophysics 116 (1978), S. 351-371 
    Details
    ISSN: 1420-9136
    Keywords: CO2 variation ; Nutrients ; Photosynthesis ; Sea surface temperature ; Upwelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Changes of atmospheric CO2 concentration since 1958 are shown to be related to sea surface temperature changes. The largest contribution to changes arises from the Pacific equatorial upwelling region, with the Indian Ocean and Atlantic contributing only small fractions to the variance. It is hypothesized that the observed relationship is related to the nutrients that are brought up by upwelling cold water, with photosynthesis contributing to a lowering of the partial pressure of CO2 in the sea and thus to a greater tendency for a flux from the air to the sea. Possible longer term variations of sea temperature and CO2 are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01636891
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Oxygen and hydrogen in the primitive atmosphere (1978)
    Springer
    Pure and applied geophysics 116 (1978), S. 222-231 
    Details
    ISSN: 1420-9136
    Keywords: Photolysis ; Photosynthesis ; Primitive Atmosphere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract From time to time there appears in the literature the assertion that photolysis of water vapor could have maintained an appreciable concentration of oxygen in the primitive (prebiological) atmosphere. The implausibility of this assertion is argued in this paper. By itself, photolysis does not provide a source of oxygen because it is usually followed by recombination of the products of photolysis. Only the escape to space (at a much smaller rate) of the hydrogen produced by photolysis of water results in a net source of oxygen. The oxidation state of the primitive atmosphere depended on the relative magnitudes of this net source of oxygen and a volcanic source of hydrogen and other reduced gases. Today the volcanic source of reduced gases is approximately equal to the oxygen source provided by photolysis followed by escape. The oxygen source depends on the mixing ratio of water vapor in the stratosphere, which ultimately determines the rate of escape of hydrogen produced from water vapor. Its magnitude may not have been very different in the past. The volcanic source of hydrogen, on the other hand, is likely to have been much larger when the earth was tectonically young. Hydrogen was therefore released to the primitive atmosphere more rapidly than oxygen, probably. Photochemical reactions with the excess hydrogen maintained oxygen mixing ratios at negligibly small levels. The hydrogen mixing ratio was determined by a balance between the volcanic source (reduced by recombination with oxygen) and escape to space. In time, either because of decline of the volcanic source of hydrogen or because of addition of a biological source of oxygen, the input of oxygen to the atmosphere rose above the input of hydrogen. The oxidation state of the atmosphere changed rapidly. Volcanic hydrogen was now consumed by photochemical reactions with excess oxygen, while the oxygen mixing ratio was determined by a balance between the source (reduced by recombination with volcanic hydrogen) and consumption in reactions with reduced material at the surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01636879
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Photosynthetic apparatus in chilling-sensitive plants (1978)
    Springer
    Planta 140 (1978), S. 121-128 
    Details
    ISSN: 1432-2048
    Keywords: Chilling ; Cold storage ; Cucumis ; Hill reaction ; Lycopersicon ; Phaseolus ; Photosynthesis ; Temperature (chilling)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Chloroplast isolated from the detached leaves of chilling-sensitive plants-Phaseolus vulgaris L., Cucumis sativus L., and Lycopersicon esculentum Mill.-stored in the cold for 2–4 days in the dark exhibit an almost complete loss of Hill reaction activity, which on illumination of leaves is restored to almost the original level. In contrast, illumination of either chloroplast suspensions or homogenates from leaves stored in the cold in the dark does not cause restoration of electron transport. Cold and dark storage of leaves of chilling-sensitive plants affects the electron transport before the site of electron donation by diphenylcarbazide and results in an increased sensitivity of the Hill reaction of isolated chloroplasts to exogenous linolenic acid. Illumination of leaves reverses these processes. When tomato plants are exposed to 0°C in intermittent light, Hill reaction activity is not affected while dark storage either at 0°C or 25°C results in a significant decrease of Hill reaction activity after 2–3 days followed by the restoration of electron transport to the original level after 1 or 2 days of the prolonged dark storage of plants. When tomato plants are stored either at 0°C in intermittent light, at 0°C in dark, or at 25°C in dark the sensitivity of the Hill reaction to exogenous linolenic acid remains increased despite a significant restoration of this activity. In conclusion, both darkness and the detachment of leaves from the plant are more effective than cold treatment in damaging photosystem II whereas both light and intact structure of the cell are required for restoration of Hill reaction activity in chloroplasts following cold and dark storage of detached leaves.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384910
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Inhibition of photosynthesis and respiration by batatasins (1978)
    Springer
    Planta 138 (1978), S. 167-172 
    Details
    ISSN: 1432-2048
    Keywords: Batatasin ; Discorea ; Dormancy ; Photophosphorylation ; Photosynthesis ; Respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of batatasins I, III and V, phenolic growth inhibitors occuring in dormant bulbils of Dioscorea batatas Decne., on photosynthetic reactions of chloroplasts from spinach (Spinacia oleracea L.) and on respiration of mitochondria from potatoes (Solanum tuberosum L.) were investigated. In chloroplasts, the batatasins effectively inhibited CO2-dependent oxygen evolution and electron flow from water to acceptors such as dichlorophenolindophenol, ferricyanide and methylviologen. Photosystem-I dependent electron transport from ascorbate to oxygen was stimulated. The proton conductivity of thylakoid membranes was increased and phosphorylation was uncoupled from electron transport. Inhibition of electron transport with water as electron donor appeared to precede uncoupling. In mitochondrial, batatasin I did not much inhibit succinate-dependent O2 uptake in the absence of ADP, but caused strong inhibition in the presence of ADP. Batatasins III and V inhibited oxygen uptake irrespective of the presence or absence of ADP. Inhibition of chloroplast and mitochondrial reactions by batatasins was shown to be reversible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391174
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    The specific radioactivity of glycolic acid in relation to the specific activity of carbon dioxide evolved in light in photosynthesizing sunflower leaves (1978)
    Springer
    Planta 138 (1978), S. 257-261 
    Details
    ISSN: 1432-2048
    Keywords: Glycolic acid ; Helianthus ; Photosynthesis ; Photorespiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Attached leaves of sunflower (Helianthus annuus L.) were exposed to 14CO2 during steady-state photosynthesis for 2 to 30 min in 345 μl/l CO2 and 21% O2 at 29° C and a light intensity of 1300 μE m-2s-1. Glycolic acid was extracted with water and diethyl ether, and was determined in the aqueous residue by high-pressure liquid column chromatography. The relative specific radioactivity of the glycolic acid synthesized during photosynthesis reached about 100% after 30 min of photosynthesis and was almost equal to that of the CO2 evolved during photorespiration, their ratio at all times being nearly one. These results provide strong in-vivo evidence that the glycolic acid is the substrate for CO2 evolved by sunflower leaves in light.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00386820
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Photosynthetic apparatus in chilling-sensitive plants (1978)
    Springer
    Planta 140 (1978), S. 129-136 
    Details
    ISSN: 1432-2048
    Keywords: Chilling ; Chloroplasts ; Cold storage ; Cucumis ; Lycopersicon ; Phaseolus ; Photosynthesis ; Temperature (chilling)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The composition of free fatty acids (FFA) in relation to Hill reaction activity and photoperoxidation of lipids was studied in chloroplasts isolated from fresh, cold and dark-stored as well as illuminated leaves of Lycopersicon esculentum Mill., Phaseolus vulgaris L. and Cucumis sativus L. Following the cold and dark-storage of leaves the loss of Hill reaction activity is accompanied by approximately a 5-fold increase in the amount of FFA and by an increase in the percentage of unsaturated FFA, particularly that of linolenic acid. Illumination of the cold- and dark-stored leaves restores both Hill reaction activity and the content and composition of chloroplast FFA. Following the second and third cycles of cold storage and illumination of leaves the percentage of unsaturated fatty acids in chloroplasts increases while that of saturated ones decreases despite of the significant restoration of Hill reaction activity. Since the illumination of cold-stored leaves results in peroxidation of inhibitory fatty acids it seems likely that this phenomenon could, at least partially, be responsible for the restoration of Hill reaction activity. Inhibition of Hill reaction activity by exogenous linolenic acid in chloroplasts of fresh, cold-stored as well as cold-stored and illuminated leaves could be reversed following the incubation of chloroplast suspension with BSA, however only to a value measured in the absence of unsaturated fatty acid. All these results indicate that the inhibition of Hill reaction activity due to the cold and dark storage of leaves is caused by both inhibitory FFA released from chloroplast lipids as well as by damage to the thylakoid structure affecting the electron transport within photosystem II.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    O2-dependent inhibition of photosynthetic capacity in intact isolated chloroplasts and isolated cells from spinach leaves illuminated in the absence of CO2 (1978)
    Springer
    Planta 142 (1978), S. 229-233 
    Details
    ISSN: 1432-2048
    Keywords: Chloroplasts ; Leaf cells ; Photoinhibition ; Photorespiration ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract When isolated intact chloroplasts or cells from spinach (Spinacia oleracea L.) leaves are incubated in the light in the absence of CO2, their capacity for subsequent CO2-dependent photosynthetic oxygen evolution is drastically decreased. This inhibition is light and oxygen-dependent and can be prevented by addition of bicarbonate. It is concluded that the normal dissipation of photosynthetic energy by carbon assimilation and in processes related to photorespiration is an essential condition for the physiological stability of illuminated intact chloroplasts and cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00388218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    Membrane potential changes during transport of hexoses in Lemna gibba G1 (1978)
    Springer
    Planta 138 (1978), S. 263-270 
    Details
    ISSN: 1432-2048
    Keywords: ATP ; Hexose transport ; Lemna ; Membrane potential ; Photosynthesis ; Respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The membrane potential (pd) of duck weed (Lemna gibba G1) proved to be energy dependent. At high internal ATP levels of 74 to 105 nmol ATP g-1 FW, pd was between -175 and -265 mV. At low ATP levels of 23 to 46 nmol ATP g-1 FW, pd was low, about -90 to -120 mV at pH 5.7, but -180 mV at pH 8. Upon addition of glucose in the dark or by light energy the low pd recovered to the high values. The active component of the pd was depolarized by the addition of hexoses in the dark and in the light. Hexose-dependent depolarization of the pd (=Δ pd) followed a saturation curve similar to active hexose influx kinetics. Depolarization of the pd recovered in the dark even in the presence of the hexoses and with a 10fold enhancement in the light. Depolarization and recovery could be repeated several times with the same cell. Glucose uptake caused a maximum depolarization of 133 mV, fructose uptake half that amount, sucrose had the same effect as glucose. During 3-O-methylglucose and 2-deoxyglucose uptake the depolarizing effect was only slightly lower. The pd remained unchanged in the presence of mannitol. The glucose dependent Δ pd and especially the rate of pd recovery proved to be pH-dependent between pH 4 and pH 8. It was independent of the presence of 1 mM KCl. Although no Δ pH could be measured in the incubation medium, these results can be best explained by a H+-hexose cotransport mechanism powered by active H+ extrusion at the plasmalemma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00386821
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Active hexose uptake in Lemna gibba G1 (1978)
    Springer
    Planta 139 (1978), S. 149-153 
    Details
    ISSN: 1432-2048
    Keywords: Hexose uptake ; Invertase ; Lemna ; Photosynthesis ; Respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Growth of autotrophically growing duck-weeds (Lemna gibba L., G1) was stimulated by sucrose. The rate of respiration increased when plants had been grown on sucrose (8.7 μmol O2 g-1 fresh weight (FW) h-1) and was reduced after growth without sucrose in the dark or under longday conditions (2.5 μmol O2 g-1 FW h-1). Photosynthesis was induced already by low light intensities (0.1 klx). Short-time application of glucose or sucrose stimulated respiration in proportion to the hexose uptake rate. Sucrose is probably not taken up as the disaccharide. The transported sugar species after addition of sucrose are its hexose moieties produced by the high activity of the cell wall invertase. Fructose stimulated to a lesser extent; mannitol induced no enhancement; 2-deoxyglucose slightly inhibited O2 uptake. After mild carbon starvation of the plants the uptake of glucose and 3-O-methylglucose proceeded without any lag phase, with similar saturation kinetics in both cases. The initial uptake rate at substrate saturation was 2.6 μmol glucose g-1 FW h-1 in the dark. Light stimulated hexose uptake by 2 to 3 times. The results show that Lemna gibba has an energy-dependent constitutive system for hexose uptake.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387140
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Photosynthesis and transpiration of the flag leaf in four spring-wheat cultivars (1978)
    Springer
    Planta 141 (1978), S. 23-28 
    Details
    ISSN: 1432-2048
    Keywords: Flag leaf ; Photosynthesis ; Transpiration ; Triticum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Co2 exchange and transpiration rates of the flag leaves of four spring wheat (Triticum aestivum L.) cultivars, namely Glenlea, Neepawa, Opal and Kolibri, were compared using infra-red gas-analysis technique. The plants were grown in a controlled environment under an 18-h photoperiod, with day and night temperatures of 20 and 15° C, respectively. The time course of the CO2-exchange rate (CER) of the flag leaf differed among cultivars. CER began to decrease rapidly some 2 weeks after ear emergence in Glenlea, Neepawa and Kolibri, but only after 4 weeks in Opal. The decline in CER of Glenlea, Neepawa and Opal was continuous throughout the period of grain development whereas in Kolibri CER was maintained at a constant level between the 4th and 6th weeks after ear emergence. The transpiration rates of the flag leaves of the 4 cultivars did not change markedly until 6–7 weeks after ear emergence, indicating that the reduction in CER was not primarily a response to increased stomatal resistance to the diffusion of CO2. Removing the ear of the main shoot of intact plants failed to depress CER of the subtending flag leaf until 5 weeks after ear removal. Removing the ears of all the tillers of plants in which all but 3 tillers had been removed at ear emergence did not depress CER until 4 weeks after ear emergence, but removal of the ear of the main shoot of plants where all the tillers had been removed at ear emergence reduced the CER of the flag leaf 2 weeks after ear removal. Removal of tillers at ear emergence had a marked effect on the time course of CER and transpiration rates of the flag leaf. Both CER and transpiration rates of a 4-tiller plant were maintained at a higher level throughout ear development as compared to those of a one-tiller plant. The transpiration rate of the flag leaf of Glenlea increased during the later part of the life of the leaf even for one-tiller plants with no ear, indicating that such a stomatal response may be part of the normal course of leaf aging and not a response to a feedback stimulus from the ear.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387739
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Oxygen inhibition of photosynthesis (1978)
    Springer
    Planta 140 (1978), S. 1-6 
    Details
    ISSN: 1432-2048
    Keywords: Leaf temperature ; Oxygen (photosynthesis) ; Photosynthesis ; Temperature (photosynthesis) ; Triticum ; Zea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of leaf temperature, O2 and calculated O2/CO2 solubility ratio in the leaf on the quantum yield of photosynthesis was studied for the C4 species, Zea mays L., and the C3 species, Triticum aestivum L. Over a range of leaf temperatures of 16 to 35° C, the quantum yield of Z. mays was relatively constant and was similar under 1.5 and 21% O2, being ca. 0.059 mol CO2 mol-1 quanta absorbed. Under 1.5% O2 and atmospheric levels of CO2, the quantum yield of T. aestivum was relatively constant (0.083 mol CO2 mol-1 quanta absorbed) at leaf temperatures from 15 to 35° C. Atmospheric levels of O2 (21%) reduced the quantum yield of photosynthesis in T. aestivum and as leaf temperature increased, the quantum yield decreased from 0.062 at 15°C to 0.046 mol CO2 mol-1 quanta absorbed at 35°C. Increasing temperature decreases the solubility of CO2 relatively more than the solubility of O2, resulting in an increased solubility ratio of O2/CO2. Experimentally manipulating the atmospheric levels of O2 or CO2 to maintain a near-constant solubility ratio of O2/CO2 at varying leaf temperatures largely prevented the temperature-dependent decrease in quantum yield in t. aestivum. Thus, the decrease in quantum yield with increasing leaf temperature in C3 species may be largely caused by a temperaturedependent change in the solubility ratio of O2/CO2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00389372
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Photosynthesis in enzymatically isolated leaf cells from the CAM plant Sedum telephium L. (1978)
    Springer
    Planta 141 (1978), S. 59-63 
    Details
    ISSN: 1432-2048
    Keywords: Crassulacean acid metabolism (CAM) ; Oxygen evolution (photosynthesis) ; Photosynthesis ; Sedum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A technique has been developed for the enzymatic isolation of leaf cells from the Crassulacean acid-metabolism plant Sedum telephium. The cells exhibited high activity in both 14CO2 incorporation (30–70 μmol CO2 mg-1 chlorophyll h-1) and O2 evolution in the presence of bicarbonate (60–110 μmol O2 mg-1 chlorophyll h-1). Half-maximum saturation of 14CO2 incorporation occurred at a bicarbonate concentration of ca. 2 mM (20 μM CO2) at pH 8.4 and 30°C. Two types of light-dependent O2 evolution are reported: O2 evolution in the absence of exogenously supplied bicarbonate (endogenous O2 evolution), and bicarbonate-stimulated O2 evolution. Oxygen evolution in the presence of approximately ambient concentrations of CO2 appeared to be a combination of the endogenous O2 evolution and O2 evolution from fixation of the exogenously supplied CO2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387745
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Carboxylating enzymes and pathway of photosynthetic carbon assmilation in different marine algae—Evidence for the C4-pathway? (1977)
    Springer
    Planta 133 (1977), S. 191-196 
    Details
    ISSN: 1432-2048
    Keywords: C4-pathway ; Dark fixation CO2 dark ; Marine macroalgae ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Experiments on short-term photosynthesis in H14CO3 - (2–5 s) using various species of different algal classes resulted in predominant 14C-labelling (〉90% of total 14C-incorporation) of phosphorylated compounds. The percentage of malate and aspartate usually accounts for distinctly less than 10% of the total 14C-labelling. These findings are consistent with data from enzymatic analyses, since 97–100% of the carboxylation capacity is due to ribulose-1.5-biphosphate carboxylase (EC 4.1.1.39) in Rhodophyceae and Chlorophyceae. Phaeophyceae are generally characterized by considerable activity of phosphoenolpyruvate carboxykinase (EC 4.1.1.32): at least 10% of carboxylation is confined to this enzyme. Similar ratios are obtained when rates of photosynthesis and of light-independent CO2-fixation are compared. Activity of phosphoenolpyruvate carboxylase (EC 4.1.1.31) could not be detected in the species investigated. The results are discussed with emphasis on the pathway of photosynthetic carbon assimilation in marine algae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391918
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Ultrastructure, polypeptide composition and photochemical activity of chloroplasts during foliar senescence of a non-yellowing mutant genotype of Festuca pratensis Huds. (1977)
    Springer
    Planta 137 (1977), S. 53-60 
    Details
    ISSN: 1432-2048
    Keywords: Chloroplast ; Festuca ; Membrane ; Photosynthesis ; Senescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A study was made of the structure and function of senescent chloroplasts from a non-yellowing (NY) mutant of Festuca pratensis. Electron microscopy suggested that the stroma matrix was destroyed but that thylakoid membranes persisted in a loose, unstacked condition. By contrast, chloroplasts from the normal (Y) genotype lost both stroma and recognizable thylakoid systems. Fraction 1, the major protein of the stroma, disappeared from Y and NY at similar rates during senescence. The activities of photosystems I and II from NY also declined at a similar rate to Y photosystems. Polypeptides of chloroplast membranes were separated by SDS gel electrophoresis into at least 30 components. There was considerable heterogeneity in rates of breakdown of the different protein species of the membranes. Of the five major polypeptide components, two had kinetics of breakdown similar to those of stroma proteins and were lost from NY and Y at about the same rate, whereas the remaining three (one of which was tentatively identified as the apoprotein of the light-harvesting chlorophyll-protein complex) were more stable in NY than in Y. These results are discussed in relation to the mechanism and function of chloroplast disintegration during leaf senescence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00394435
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Nature of light requirement for the flowering of Chenopodium rubrum L. (Ecotype 60° 47′ N) (1977)
    Springer
    Planta 133 (1977), S. 103-106 
    Details
    ISSN: 1432-2048
    Keywords: Chenopodium rubrum ; Flowering ; High Energy Reaction ; Photosynthesis ; Phytochrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Seedlings of C. rubrum were irradiated with different light qualities and intensities following a single inductive dark period. Our results show that relatively low intensity white light (35–100 ft. c.) does not support flower development while high intensity white light (650–800 ft. c.) permits 100% flowering. We have shown that the low intensity light inhibiton of flower development is not due to suboptimal photosynthesis. Relatively low intensities of light rich in far-red or blue wavebands sustains optimum flower development, whereas red light is totally ineffective in this respect. Considering that the intensity dependent High Energy Reaction (HER) has its action maxima in the blue and far-red we propose that HER may be positively involved in the flower development of C. rubrum. Our study further suggests that there may be some flower inhibitory component at play in relatively low intensity white light conditions and HER may be required to counteract this flower inhibitory effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391905
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    Fluorescence induction in whole leaves: Differentiation between the two leaf sides and adaptation to different light regimes (1977)
    Springer
    Planta 133 (1977), S. 121-129 
    Details
    ISSN: 1432-2048
    Keywords: Energy distribution ; Fluorescence induction ; Light adaptation ; Photosynthesis ; Photosynthetic unit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In a variety of plants, the induction kinetics of chlorophyll fluorescence vary substantially depending on whether measured on the upper or lower side of the same leaf. The responses are comparable to those of plants grown under sun and shade conditions. Leaf morphology appears not to be the primary cause of the differences since inversion of the leaves can lead to reversed fluorescence responses. Fluorescence induction was analyzed in control and inverted leaves, and in one case, in chloroplasts from sun and shade leaves. It is concluded from the data that the major differences between the chloroplasts of the upper and lower leaf side reflect ionic and thylakoidmembrane conformational factors, rather than structural differences. Mg2+ flux probably plays a significant role in the adjustment of the thylakoid membrane to high or low light conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391909
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Nature of light requirement for the flowering of Chenopodium rubrum L. (Ecotype 60° 47′ N) (1977)
    Springer
    Planta 133 (1977), S. 97-102 
    Details
    ISSN: 1432-2048
    Keywords: Chenopodium rubrum ; Flowering ; High Energy Reaction ; Photosynthesis ; Phytochrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Seedlings of the short-day plant, Chenopodium rubrum L. (Ecotype 60° 47′ N) were irradiated with different intensities and qualities of light for 24 h preceding a single inductive dark period (12 h). Our data shows that a relatively low intensity incandescent light (35–100 ft. c.) is not effective as the photoperiod for flowering. The above effect is not due to a requirement for a relatively high level of photosynthesis. Our results suggest a definite promotory role of a blue High Energy Reaction (HER). We could not demonstrate the involvement of a far-red HER. We suggest that ineffectiveness of far-red may have been due to establishment of rather low Phytochrome, P FR , levels, suboptimal for flowering. A certain critical level of P FR (30–40%, that presumably established by blue light) seems to be necessary for photoreactions involved in flowering of C. rubrum. There are indications in our experiments of the operation of a red radiation mediated flower inhibitory photoreaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391904
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    C4-Dicarboxylic acid metabolism in bundle-sheath chloroplasts, mitochondria and strands of Eriochloa borumensis Hack., a phosphoenolpyruvate-carboxykinase type C4 species (1977)
    Springer
    Planta 133 (1977), S. 135-144 
    Details
    ISSN: 1432-2048
    Keywords: Acids, dicarboxylic ; CO2 fixation ; Eriochloa ; Gramineae ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract C4-acid metabolism by isolated bundlesheath chloroplasts, mitochondria and strands of Eriochloa borumensis Hack., a phosphoennolpyruvate-carboxykinase (PEP-CK) species, was investigated. Aspartate, oxaloacetate (OAA) and malate were decarboxylated by strands with several-fold stimulation upon illumination. There was strictly light-dependent decarboxylation of OAA and malate by the chloroplasts, but the chloroplasts did not decarboxylate aspartate in light or dark. PEP was a primary product of OAA or malate decarboxylation by the chloroplasts and its formation was inhibited by 3-(3,4-dichlorophenyl)-1, 1-dimethylurea or NH4Cl. There was very little conversion of PEP to pyruvate by bundle-sheath chloroplasts, mitochondria or strands. Decarboxylation of the three C4-acids by mitochondria was light-independent. Pyruvate was the only product of mitochondrial metabolism of C4-acids, and was apparently transaminated in the cytoplasm since PEP and alanine were primarily exported out of the bundle-sheath strands. Light-dependent C4-acid decarboxylation by the chloroplasts is suggested to be through the PEP-CK, while the mitochondrial C4-acid decarboxylation may proceed through the NAD-malic enzyme (NAD-ME) system. In vivo both aspartate and malate are considered as transport metobolites from mesophyll to bundle-sheath cells in PEP-CK species. Aspartate would be metabolized by the mitochondria to OAA. Part of the OAA may be converted to malate and decarboxylated through NAD-ME, and part may be transported to the chloroplasts for decarboxylation through PEP-CK localized in the chloroplasts. Malate transported from mesophyll cells may serve as carboxyl donor to chloroplasts through the chloroplastic NAD-malate dehydrogenase and PEP-CK. Bundle-sheath strands and chloroplasts fixed 14CO2 at high rates and exhibited C4-acid-dependent O2 evolution in the light. Studies with 3-mercaptopicolinic acid, a specific inhibitor of PEP-CK, have indicated that most (about 70%) of the OAA formed from aspartate is decarboxylated through the chloroplastic PEP-CK and the remaining (about 30%) OAA through the mitochondrial NAD-ME. Pyruvate stimulation of aspartate decarboxylation is discussed; a pyruvate-alanine shuttle and an aspartate-alanine shuttle are proposed between the mesophyll and bundle-sheath cells during aspartate decarboxylation through the PEP-CK and NAD-ME system respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00391911
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Carbon isotope composition of biochemical fractions isolated from leaves of Bryophyllum daigremontianum berger, a plant with crassulacean acid metabolism: Some physiological aspects related to CO2 dark fixation (1977)
    Springer
    Planta 135 (1977), S. 241-248 
    Details
    ISSN: 1432-2048
    Keywords: Carbon dioxide dark fixation ; Carbon isotope ratio ; Crassulacean acid metabolism ; Glycolysis ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Isotope analysis of the biochemical fractions isolated quantitatively from young and mature leaves of Bryophyllum daigremontianum Berger have been carried out before and after a dark period of accumulation of organic acids. The mature leaf is enriched in 13C compared to the young leaf. The δ13C values of the different leaf constituents vary between the δ13C values of C4 plants (-11‰) and those of C3 plants (-27‰). During the dark period, the two types of leaves store organic acids with δ13C values of ≃-15‰ and lose insoluble sugars, including starch with a δ13C value of ≃-12‰. Furthermore, young leaves store phosphorylated compounds with δ13C values of ≃-11‰ and lose weakly polymerised sugars with δ13C values of ≃-18‰. These results led to the formulation of a hypothesis of the origin of the two substrates of β-carboxylation: phosphoenolpyruvate arises from the glycolytic breakdown of the insoluble sugars rich in 13C, and the major portion of the CO2 is the result of the complete breakdown (respiration) of the soluble sugars rich in 12C. The existence of two independent sugar pools leads to the assumption that there are two separate glycolytic pathways. The 13C enrichment of the stored products of the young leaves in the day seems to be the result of a weak discrimination for 13C by ribulose diphosphate carboxylase, which reassimilates to a great extent the CO2 released from malate accumulated in the night.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384896
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    The effect of atmospheric humidity on photosynthesis, transpiration and water use efficiency of leaves of several plant species (1977)
    Springer
    Planta 134 (1977), S. 5-10 
    Details
    ISSN: 1432-2048
    Keywords: Humidity ; Photosynthesis ; Transpiration ; Water use efficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of humidity on the gas exchange of leaves of the dicotyledons soybean (Glycine max (L.) Merrill), sunflower (Helianthus annuus L.), jojoba (Simmondsia chinensis (L.) Schneider), and saltbush (Atriplex halimus L.) and the monocotyledons wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) sorghum (Sorghum bicolor (L.) Moench) and barnyard grass (Echinochloa crus-galli (L.) Beauv.) was examined under conditions of adequate soil moisture in a controlled environment. Photosynthesis and stomatal and internal diffusion resistances of whole, attached, single leaves were not affected by changes in humidity as the vapour pressure deficit between the leaf and atmosphere ranged from 8 to 27 mb. Transpiration increased linearly with increasing vapour pressure deficit. Whole plants of barley exhibited a different response. As humidity was increased, photosynthesis increased, transpiration expressed per unit of vapour pressure difference increased, and diffusion resistances became smaller. Reasons for the different behaviour of single leaves and whole plants are suggested. An index for water use efficiency, expressed per millibar of vapour pressure deficit, was calculated for single leaves of each species used in the experiments. This showed that water use efficiency was highest in the C4 xerophytes and lowest in the C3 mesophytes. The effect of environment on water use efficiency is examined using data from the literature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00390086
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Ecotypic differences in the C3 and C4 photosynthetic activity in Mollugo verticillata, a C3−C4 intermediate (1977)
    Springer
    Planta 134 (1977), S. 257-262 
    Details
    ISSN: 1432-2048
    Keywords: C4 plants ; Ecotype ; Mollugo ; Photorespiration ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four populations of Mollugo verticillata L. were compared on the basis of their photosynthetic products, photosynthetic rates, enhancement under low oxygen concentration, and CO2 compensation points. In addition, pulse-chase labeling experiments were conducted using one of the four populations. Depending on the plant population, C4 acids ranged from 40% to 11% of the primary products under short-term exposure to 14CO2. These compounds were also metabolized during pulse-chase experiments. All four populations had significantly different photosynthetic rates and those rates were correlated with the amounts of labelled C4 acids produced and C4-acid turnover. Three populations of M. verticillata had similar compensation points (40 μl/l) and degrees of photosynthetic enhancement under low [O2] (20%), the fourth population was much lower in both characteristics (CO2 compensation, 25 μl/l; low-O2 enhancement, 12%). The results verify the intermediate nature of photosynthesis in this species, and illustrate populational differences in its photosynthetic and photorespiratory carbon metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384190
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Influence of certain environmental factors on photosynthesis and photorespiration in Simmondsia chinensis (1977)
    Springer
    Planta 134 (1977), S. 127-132 
    Details
    ISSN: 1432-2048
    Keywords: Gas exchange ; Oxygen inhibition ; Photorespiration ; Photosynthesis ; Simmondsia ; Water stress
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The response of net photosynthesis and apparent light respiration to changes in [O2], light intensity, and drought stress was determined by analysis of net photosynthetic CO2 response curves. Low [O2] treatment resulted in a large reduction in the rate of photorespiratory CO2 evolution. Lightintensity levels influenced the maximum net photosynthetic rate at saturating [CO2]. These results indicate that [CO2], [O2] and light intensity affect the levels of substrates involved in the enzymatic reactions of photosynthesis and photorespiration. Intracellular resistance to CO2 uptake decreased in low [O2] and increased at low leaf water potentials. This response reflects changes in the efficiency with which photosynthetic and photorespiratory substrates are formed and utilized. Water stress had no effect on the CO2 compensation point or the [CO2] at which net photosynthesis began to saturate at high light intensity. The relationship between these data and recently published in-vitro kinetic measurements with ribulose-diphosphate carboxylase is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00384961
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    The role of vanadium in green plants (1977)
    Springer
    Archives of microbiology 114 (1977), S. 67-70 
    Details
    ISSN: 1432-072X
    Keywords: Chlorella pyrenoidosa ; Chlorophyll formation ; Dry weight ; Photosynthesis ; Toxicity ; Vanadium ; Vanadium content ; Vanadate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cells of Chlorella pyrenoidosa, derived from vanadium free agar slants, respond with great sensitivity to microamounts of vanadium, added as NH4VO3 to autotrophic liquid cultures. Between 0.01 and 1 μg V per litre nutrient medium (2·10-10-2·10-8g-at/l), the algae respond with a continuous increase in dry weight. At higher V-concentrations, further enhancement in biomass is accompanied by a additional increase in chlorophyll content. Maximum V-effect on both parameters was found to be at 500μg V/l (10-5 g-at/l). Dry weight as well as chlorophyll content of Chlorella are decreased by concentrations above 25 mg V/l; 100 mg V/l (2·10-3 g-at/l) stop growth and cause death of the cells. The toxic threshold for the V-content in the algae was determined to be at 150–200 μg V/g (3–4·10-6 g-at/g) dry weight. Two different pH-optima for a positive vanadium action on dry weight and chlorophyll biosynthesis were established, the first at pH 7, the other in the range pH 7.5–8. Two sites of vanadium action in green algae are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00429632
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Inhibition of oxygen release by anoxia in a C3-plant (Nicotiana tabacum cv. Wisconsin 38). Comparison with C4-plants (1977)
    Springer
    Planta 135 (1977), S. 39-43 
    Details
    ISSN: 1432-2048
    Keywords: Anaerobiosis inhibition ; C3/C3 plants ; Nicotiana ; Oxygen-release ; Photosynthesis ; Zea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Tobacco leaves (Nicotiana tabacum var. Wisconsin 38) submitted to anaerobic conditions behave in a manner similar to that of maize, sugarcane, or sorghum leaves (C4-plants); more precisely, a lag time in O2 release is exhibited when the leaves are exposed to light after treatment in the dark under pure nitrogen. Although the conditions for the appearance of this phenomenon in tobacco are somewhat different, the main features are identical to those observed with maize: abolition of the lag time upon immediate exposure to light, release of CO2 under light (illumination burst of CO2), photochemical nature of the reactions involved in the abolition of the lag time, activation of oxygen release by far-red light, and the antagonistic effect of red and far-red light on the lag time. The high CO2 compensation point of tobacco leaves permits the classification of this plant among the C3 group. A comparison of these experimental results with others from the literature suggests than the distinguishing features between C3- and C4-plants are not as sharp as generally thought.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00387973
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    The interaction of nitrogen assimilation with photosynthesis in nitrogen deficient cells of Chlorella (1976)
    Springer
    Planta 133 (1976), S. 9-13 
    Details
    ISSN: 1432-2048
    Keywords: Nitrogen assimilation ; Respiration ; Photosynthesis ; Chlorella
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Nitrogen-limited chemostat cultures of Chlorella fusca var. vacuolata, when given nitrogen in the inorganic forms of nitrate, nitrite and ammonium divert photo-generated electrons, from CO2 fixation to nitrogen assimilation. Addition of nitrate or nitrite, but not ammonium, stimulates rate of oxygen evolution. All but the most severely nitrogen-deficient culture have increased dark respiration rates after addition of inorganic nitrogen. The nitrite reduction step of nitrogen assimilation is the most light-dependent reaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00385999
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Characterization and structural properties of the major biliproteins of Anabaena sp. (1976)
    Springer
    Archives of microbiology 110 (1976), S. 61-75 
    Details
    ISSN: 1432-072X
    Keywords: Biliproteins ; Phycoerythrocyanin ; Assembly forms ; Anabaena sp. ; Photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Studies are presented of the biliproteins of Anabaena sp. This filamentous cyanobacterium contains three major biliproteins. Whereas two of these, C-phycocyanin and allophycocyanin, are common to all cyanobacteria, the third, phycoerythrocyanin (λmax∼568nm) has hitherto not been described and its distribution among cyanobacteria appears to be limited. Anabaena variabilis and Anabaena sp. 6411 allophycocyanin, C-phycocyanin, and phycoerythrocyanin were purified to homogeneity and characterized with respect to molecular weight, isoelectric point, absorption spectrum and amino acid composition. The α and β subunits of each of these proteins were also purified to homogeneity and characterized in the same manner. The tetrapyrrole chromophore content was determined for each of the proteins and subunits. The α subunit of phycoerythrocyanin carries a novel phycobiliviolin-like chromophore. This chromophore has not previously been detected in cyanobacterial biliproteins, but has been noted as a prosthetic group of a cryptophytan phycocyanin. Sedimentation equilibrium studies show that at pH 7.0, at protein concentrations of 0.2–0.6 mg/ml, allophycocyanin, C-phycocyanin and phycoerythrocyanin, each exists as a trimeric aggregate, (αβ)3, of molecular weight of approximately 105000. Structural studies of microcrystals of these three biliproteins by electron microscopy and X-ray diffraction reveal a common plan for the construction of higher assembly forms. The major building block appears to be the trimer (αβ)3. It is proposed that this is a dise-like structure about 3.0×12.0 nm. The individual α or β subunits are roughly spherical, 3 nm in diameter. Allophycocyanin trimers stack to form bundles of rods which form long needles. Both phycocyanin and phycoerythrocyanin form double dises (αβ)6 which are visible as ring-shaped structures by electron microscopy. The mode of assembly of the biliproteinstructures in the phycobilisome is, as yet, unknown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00416970
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Photoproduction of ammonium ion from N2 inRhodospirillum rubrum (1976)
    Springer
    Archives of microbiology 110 (1976), S. 207-213 
    Details
    ISSN: 1432-072X
    Keywords: Nitrogen fixation ; NH 4 + excretion ; Photosynthesis ; Rhodospirillum rubrum ; Photosynthetic bacteria ; Enzymes of ammonia assimilation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract NH 4 + excretion was undetectable in N2-fixing cultures ofRhodospirillum rubrum (S-1) and nitrogenase activity in these cultures was repressed by the addition of 10 mM NH 4 + to the medium. The glutamate analog,l-methionine-dl-sulfoximine (MSX), derepressed N2 fixation even in the presence of 10 mM extracellular NH 4 + . When 10 mg MSX/ml was added to cultures just prior to nitrogenase induction they developed nitrogenase activity (20% of the control activities) and excreted most of their fixed N2 as NH 4 + . Nitrogenase activities and NH 4 + production from fixed N2 were increased considerably when a combined nitrogen source, NH 4 + (〉40 μmoles NH 4 + /mg cell protein in 6 days) orl-glutamate (〉60 μmoles NH 4 + /mg cell protein in 6 days) was added to the cultures together with MSX. Biochemical analysis revealed thatR. rubrum produced glutamine synthetase and glutamate synthase (NADP-dependent) but no detectable NADP-dependent glutamate dehydrogenase. The specific activity of glutamine synthetase was observed to be maximal when nitrogenase activity was also maximal. Nitrogenase and glutamine synthetase activities were repressed by NH 4 + as well as by glutamate. The results demonstrate that utilization of solar energy to photoproduce large quantities of NH 4 + from N2 is possible with photosynthetic bacteria by interfering with their regulatory control of N2 fixation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00690229
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    The coupling effects of some thiol and other sulfur-containing compounds on the circadian rhythm of cell division in photosynthetic mutants of Euglena (1976)
    Springer
    Archives of microbiology 108 (1976), S. 1-8 
    Details
    ISSN: 1432-072X
    Keywords: Euglena ; Mutants ; Circadian rhythm ; Algae ; Biological clock ; Cell division ; Photosynthesis ; Cell cycle ; Thiols ; Synchrony
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Previous work has demonstrated a persisting, free-running, circadian rhythm of cell division in the P4ZUL photosynthetic mutant of the alga Euglena gracilis Klebs (Strain Z) Pringsheim grown organotrophically in continuous light or darkness at 19° C following prior synchronization by a repetitive LD: 10,14 light cycle. A similar circadian rhythmicity has been recently discovered in the W6ZHL heat-bleached and the Y9ZNalL naladixic acid-induced mutants of Euglena grown under comparable conditions. Over extended timespans, however, these mutants appear to gradually lose first their ability to display persisting overt rhythms, and then even their capability of being entrained by imposed LD cycles. These properties can be restored by the addition of certain sulfur-containing compounds to the medium including cysteine, methionine, dithiothreital, sodium monosulfide, sodium sulfite, and sodium thiosulfate, as well as thioglycolic [mercaptoacetic] acid. The implications of these findings toward biological clock mechanisms are discussed: It appears that some sort of coupling process is operating as opposed to the initiation of an underlying oscillation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425086
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Effect of some environmental factors on cyanophage AS-1 development in Anacystis nidulans (1976)
    Springer
    Archives of microbiology 110 (1976), S. 55-60 
    Details
    ISSN: 1432-072X
    Keywords: Cyanophage ; Blue-green algae ; Blue-green algal virus ; AS-1 ; Anacystis nidulans ; Phage development ; Photosynthesis ; Synechococcus 6301
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The development cycle of the cyanophage AS-1 was studied in the host blue-green alga, Anacystis nidulans, under conditions that impair photosynthesis and under various light/dark regimes. Under standard conditions of incubation the 16-h development cycle consisted of a 5-h eclipse period and an 8-h latent period. Burst size was decreased by dark incubation to 2% of that observed in the light. An inhibitor of photosystem II, 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU), reduced the burst size to 27% of that of the uninhibited control, whereas cyanophage production was completely abolished by carbonyl-cyanide m-chlorophenyl hydrazone (CCCP), an inhibitor of photosynthetic electron transport. Dark incubation of infected cells decreased the latent period by 1–2 h and the eclipse period by 1 h, once the cultures were illuminated. This suggests that adsorption took place in the dark. Intracellular growth curves indicated that light is necessary for viral development. Infected cells must be illuminated at least 13 h to produce a complete burst at the same rate as the continuously illuminated control. Low light intensities retarded the development cycle, and at lowest light intensities no phage yield was obtained. AS-1 is highly dependent on host cell photophosphorylation for its development.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00416969
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Ribulose 1,5-diphosphate carboxylase and Chlorobium thiosulfatophilum (1976)
    Springer
    Archives of microbiology 109 (1976), S. 15-19 
    Details
    ISSN: 1432-072X
    Keywords: Chlorobium thiosulfatophilum ; Ribulose 1,5-diphosphate crboxylase ; Phosphoribulokinase ; Photosynthesis ; CO2 assimilation ; Reductive pentose phosphate cycle ; Reductive carboxylic acid cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Cell-free extracts of the photosynthetic bacterium Chlorobium thiosulfatophilum, strains 8327 and Tassajara, were assayed for ribulose 1,5-diphosphate (RuDP) carboxylase and phosphoribulokinase-the two enzymes peculiar to the reductive pentose phosphate cycle. 2. RuDP carboxylase was consistently absent in strain 8327. The Tassajara strain showed a low RuDP-dependent CO2 fixation activity that was somewhat higher in cells following transatlantic air shipment than in freshly grown cells. The stability and behaviour of this activity in sucrose density gradients were similar to those described by other workers. 3. The radioactive carboxylation products formed in the presence of RuDP by enzyme preparations from the Tassajara strain did not include 3-phosphoglycerate-the known product of the RuDP carboxylase reaction, but instead consisted of the unrelated acids glutamate, aspartate and malate. 4. Phosphoribulokinase was absent in all preparations of the two Chlorobium strains tested. By contrast, phosphoribulokinase as well as RuDP carboxylase were readily demonstrated in preparations from pea chloroplasts and the photosynthetic bacterium Rhodospirillum rubrum. 5. It is concluded that C. thiosulfatophilum appears to lack RuDP carboxylase, phosphoribulokinase, and hence, the reductive pentose phosphate cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425107
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Physiological effects of the presence and absence of gas vacuoles in the blue-green alga,Microcystis aeruginosa Kuetz. emend. Elenkin (1976)
    Springer
    Archives of microbiology 110 (1976), S. 225-231 
    Details
    ISSN: 1432-072X
    Keywords: Blue-green algae ; Gas vesicles ; Gas vacuoles ; Pseudovacuoles ; Growth ; Photosynthesis ; Oxygen evolution ; Pigments ; Light shielding ; Volume regulation ; Free space
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Physiological evidence was obtained for a light shielding role for gas vacuoles inMicrocystis aeruginosa Kuetz. emend. Elenkin, by comparing photosynthetic oxygen evolution, growth behaviour and pigment composition of cells with intact or collapsed gas vacuoles. The oxygen evolution rates were strongly dependent on cell concentration, a maximum rate for cells with intact gas vacuoles occurring at about 1.4×109 cells/ml and for cells with collapsed gas vacuoles at about 2.5×109 cells/ml. By using light saturation curves for oxygen evolution, it was estimated that at low light intensities up to 30% of the photosynthetically useable light was shielded at a cell concentration of 6×108 cells/ml. Collapsing the gas vacuoles twice daily did not alter the initial growth rate of the cultures, but enabled them to reach a higher final cell density. Collapsing of gas vacuoles during growth for about four generations resulted in a lower level of all acetone soluble pigments with a greater relative reduction in carotenoids than in chlorophyll a. Collapse of the gas vacuoles does not alter the cell volume. Various optical interactions which could account for light shielding are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00690231
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Some preliminary observations on the enhancement of phytoplankton growth by low levels of mineral hydrocarbons (1976)
    Springer
    Hydrobiologia 51 (1976), S. 85-89 
    Details
    ISSN: 1573-5117
    Keywords: Hydrocarbons ; Nanoplankton ; µ-Flagellates ; Photosynthesis ; Haptophyceae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract From field and laboratory experiments it has been observed that low concentrations (ppb) of mineral hydrocarbons can cause an increase in photosynthesis among the nanoplankton. In field experiments, the increase in photosynthetic activity among the nanoplankton led to a bloom of µ-flagellates predominated by a member of the Haptophyceae,Chrysochromulina kappa.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00007989
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Effects of diazepam on photosynthesis, respiration, rubidium uptake, and finestructure of Scenedesmus obliquus in synchronous cultures (1975)
    Springer
    Archives of microbiology 102 (1975), S. 129-137 
    Details
    ISSN: 1432-072X
    Keywords: Diazepam ; Benzodiazepines ; Scenedesmus ; Ultrastructure ; Photosynthesis ; Respiration ; Rubidium Uptake
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of diazepam (Valium) on photosynthesis, chlorophyll/photosynthesis ratios, respiration, uptake of rubidium ions, and ultrastructure of Scenedesmus obliquus synchronized by a light-dark regimen of $$14:\overline {10}$$ hrs were determined. 80 and 160 μM diazepam, added to the nutrient medium at the start of the light-dark change (i.e., start of the cell cycle) gradually reduced rates of photosynthesis below the initial rates from the beginning of the experiment. Contents of chlorophyll, however, remained nearly unaffected. Consequently, the diazepam-treated cells had a higher chlorophyll/photosynthesis ratio—also with regard to respiration in order to calculate the gross photosynthesis. The occurrence of photorespiration cannot be assumed. The net influx or rubidium was slightly reduced by 100 μM diazepam 0.5 and 2.0 hrs after the start of the cell cycle and was strongly inhibited after 5 to 14 hrs. 80 and 160 μM diazepam caused separation of thylakoids, formation of giant mitochondria and enlargement of vacuoles. The results are discussed and it is finally suggested that diazepam acts on different membrane systems. Furthermore an ATP deficiency cannot be excluded.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00428357
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Photoassimilation of acetate and metabolism of carbohydrate in Chlorobium thiosulfatophilum (1975)
    Springer
    Archives of microbiology 104 (1975), S. 105-111 
    Details
    ISSN: 1432-072X
    Keywords: Chlorobium thiosulfatophilum ; Photosynthesis ; Carbon Pathway ; Photoassimilation ; Microbial Degradation of Glucose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Washed cell suspensions of Chlorobium thiosulfatophilum form large amounts of a polyglucose in the light. Addition of acetate to the cells increases the formation of polysaccharide considerably. During incubation in the dark, polysaccharide decreases with time, and organic acids such as succinic and propionic acid are excreted into the medium. 2. Glucose isolated from cells which had photoassimilated 1-, 2-, and U-14C-acetate had a specific activity which lay between 1 and 2 times that of the acetate substrates. 3. To analyse the distribution of radioactivity in the glucose units formed during photoassimilation of 14C-acetate, 2 microbial degradations, with bakers' yeast and Zymomonas mobilis respectively, were used. The results show that acetate gives rise to carbon atoms 1+2 and 5+6 of glucose, whereas carbon atomes 3+4 are not labelled. Further, the results indicate that glucose is not formed via the reductive pentose phosphate cycle when acetate is present.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Requirement of low oxidation-reduction potential for photosynthesis in a blue-green alga (Phormidium sp.) (1975)
    Springer
    Archives of microbiology 104 (1975), S. 7-13 
    Details
    ISSN: 1432-072X
    Keywords: Photosynthesis ; Blue-Green Alga ; Phormidium sp. ; Oxidation-Reduction Potential ; Sulfide ; Hot Spring ; Stronatolite ; Anaerobiosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Photosynthesis in a Phormidium species which forms dense conical-shaped structures in thermal springs is strongly inhibited by aeration but is stimulated by sulfide and other agents (cysteine, thioglycolate, sulfite) which lower the oxidation-reduction potential. The compact structures which this alga forms in nature may restrict oxygen penetration from the environment so that the anaerobic or microaerophilic conditions necessary for photosynthesis can develop. The alga may be defective in a regulatory mechanism that controls the reoxidation of reduced pyridine nucleotides formed during photosynthesis. It is suggested that other mat-forming and benthic blue-green algae may also prefer anaerobic conditions for growth and photosynthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447293
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...