Abstract
Evidence for a cyclic electron flow has been sought by study of the steady-state poise of P700 and rate of photoreaction 1 in three cyanobacteria. Under an actinic light 1 (440 or 680 nm) the rate of photoreaction 1 is limited by the rate of electron supply provided by photoreaction 2 and by all return electron flow from low potential donors such as ferredoxin and NAD(P)H. Plots of p, the steady-state fraction of P700 reduced, versus the reciprocal intensity, 1/I, yield linear segments of slope Ip. From considerations of a simple model the slopes and extrapolated intercepts of the linear segments provide estimates of the rate of return electron flow. Analysis shows that the total return electron flow cannot be large, by one estimate not more than three times the rate of dark respiration. This result leads to a conclusion that cyclic electron flow (and any dependent phosphorylation) is not a significant process in these cyanobacteria at ordinary light intensities.
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Abbreviations
- DAD:
-
diaminodurene
- PMS:
-
phenazine methosulfate
References
Avron M and Neuman J (1968) Photophosphorylation in chloroplasts Ann Rev Plant Physiol 19: 137–166
Bottomly PJ and Stewart WDP (1976) ATP pools and transients in the blue-green alga, Anabaena cylindrica. Arch Microbiol 108: 246–258
Chain RK and Arnon DI (1977) Quantum efficiency of photosynthetic energy conversion. Proc Natl Acad Sci USA 74: 377–3381
Gimmler H (1977) Photophosphorylation in vivo. In: Trebst A and Avron M (eds), Encyclopedia of Plant Physiology New Series. Vol 5 Photosynthesis I, pp 448–472. Berlin, Heidelberg: Springer
Hatchard CG and Parker CA (1956) Potassium ferrioxalate as a standard chemical actinometer. Proc Roy Soc London A235: 518–536
Hauska G, Reimer S and Trebst A (1974) Native and artificial energy-conserving sites in cyclic photophosphorylation systems. Biochim Biophys Acta 357: 1–13
Hirano M, Satoh K and Katoh S (1986) Plastoquinone as a common link between photosynthesis and respiration in a blue-green alga. Photosyn Res 9: 135–147
Hiyama T, McSwain BD and Arnon DI (1977) P700 and the photoreduction of NADP+ in chloroplast fragments. Biochim Biophys Acta 460: 65–75
Hiyama T, McSwain BD and Arnon DI (1977) Evidence for two types of P700 in membrane fragments from a blue-green alga. Biochim Biophys Acta 460: 76–84
Hoch G, Owens H and Kok B (1963) Photosynthesis and respiration. Arch Biochem Biophys 101: 171–180
Myers J (1986) Photosynthetic and respiratory electron transport in a cyanobacterium. Photosyn Res 9: 135–147
Myers J and Graham JR (1971) The photosynthetic unit in Chlorella measured by repetitive short flashes. Plant Physiol 48: 282–286
Myers J, Graham JR and Wang RT (1980) Spontaneous pigment mutants of Anacystis nidulans selected by growth under far-red light. Arch Microbiol 124: 143–148
Rippka R, Derulles J, Waterbury JB, Herdman M and Stanier RY (1979) Generic assignment, strain histories, and properties of pure cultures of cyanobacteria J Gen Microbiol 111: 1–16
Sandman G and Malkin R (1983) NADH and NADPH as electron donors to respiratory and photosynthetic transport in the blue-green alga, Aphanocapsa. Biochim Biophys Acta 725: 221–224
Simonis W and Urbach W (1973) Photosynthetic phosphorylation in vivo. Annu Rev Plant Physiol 24: 89–114
Wang RT and Myers J (1976) On the distribution of excitation energy to two photoreactions of photosynthesis Photochem Photobiol 23: 405–410
Wang RT, Stevens CLR and Myers J (1977) Action spectra for photoreactions I and II of photosynthesis in the blue-green alga Anacystis nidulans. Photochem Photobiol 25: 103–108
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Myers, J. Is there significant cyclic electron flow around photoreaction 1 in cyanobacteria?. Photosynth Res 14, 55–69 (1987). https://doi.org/10.1007/BF00019592
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DOI: https://doi.org/10.1007/BF00019592