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
  • Articles  (66,958)
  • Springer Nature  (63,835)
  • Macmillan Magazines Ltd.  (2,351)
  • Blackwell Publishing Ltd  (772)
  • American Meteorological Society
  • International Union of Crystallography
  • Springer Science + Business Media
  • 2000-2004  (40,043)
  • 1960-1964  (26,915)
  • Medicine  (66,958)
Collection
  • Articles  (66,958)
Source
Publisher
Years
Year
Journal
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Endoribonuclease RNase III is essential in Bacillus subtilis (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The rncS gene of Bacillus subtilis encodes Bs-RNase III, a narrow-specificity endoribonuclease. Previous attempts to disrupt rncS were unsuccessful. Here, a strain was constructed in which Bs-RNase III expression was dependent upon transcription of rncS from a temperature-sensitive plasmid. Growth of this strain at the non-permissive temperature resulted in 90–95% cell death, and virtually all the cells that survived retained the rncS-expressing plasmid. Thus, we conclude that rncS is essential in B. subtilis. The rncS conditional strain also revealed that Bs-RNase III participates in the processing of ribosomal RNA, in addition to processing small cytoplasmic RNA, a member of the signal recognition particle RNA family. Most significantly, a rare rncS null strain was isolated that will aid further study of the critical role Bs-RNase III plays in B. subtilis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02185.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The HspR regulon of Streptomyces coelicolor: a role for the DnaK chaperone as a transcriptional co-repressor† (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The dnaK operon of Streptomyces coelicolor encodes the DnaK chaperone machine and HspR, the transcriptional repressor of the operon; HspR confers repression by binding to several inverted repeat sequences in the promoter region, dnaKp. Here, we demonstrate that HspR specifically requires the presence of DnaK protein to retard a dnaKp fragment in gel-shift assays. This requirement is independent of the co-chaperones, DnaJ and GrpE, and it is ATP independent. Furthermore the retarded protein–DNA complex can be ‘supershifted’ by anti-DnaK monoclonal antibody, demonstrating that DnaK forms an integral component of the complex. It was shown in DNase I footprinting experiments that refolding and specific binding of HspR to its DNA target does not require DnaK. We conclude that the formation of the stable DnaK–HspR–DNA ternary complex does not depend on the chaperoning activity of DnaK. In affinity chromatography experiments using whole-cell extracts, DnaK was shown to co-purify with HspR, providing additional evidence that the two proteins interact in vivo; it was not possible to purify HspR away from DnaK in any experiments unless a powerful denaturant was used. The level of heat shock induction of chromosomal DnaK could be partially suppressed by expressing dnaK extrachromosomally from a heterologous promoter. In addition, it is shown that DnaK confers enhanced HspR-mediated repression of transcription in vitro. Taken together, these results suggest that DnaK functions as a transcriptional co-repressor by binding to HspR at its operator sites. In this model, the DnaK–HspR system would represent a novel example of feedback regulation of gene expression by a molecular chaperone, in which DnaK directly activates a repressor, rather than inactivates an activator (as is the case in the DnaK–σ32 and Hsp70–HSF systems of other organisms).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02194.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    New prospects in studying the bacterial signal recognition particle pathway (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: In vivo and in vitro studies have suggested that the bacterial version of the mammalian signal recognition particle (SRP) system plays an essential and selective role in protein biogenesis. The bacterial SRP system consists of at least two proteins and an RNA molecule (termed Ffh, FtsY and 4.5S RNA, respectively, in Escherichia coli). Recent evidence suggests that other putative bacterial-specific SRP components may also exist. In vitro experiments confirmed the expected basic features of the bacterial SRP system by demonstrating interactions among the SRP components themselves, between them and ribosomes, ribosome-linked hydrophobic nascent polypeptides or inner membranes. The availability of a conserved (and essential) bacterial SRP version has facilitated the implementation of powerful genetic and biochemical approaches for studying the cascade of events during the SRP-mediated targeting process in vivo and in vitro as well as the three-dimensional structures and the properties of each SRP component and complex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02198.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Characterization of the MFα pheromone of the human fungal pathogen Cryptococcus neoformans (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Cryptococcus neoformans is an important human pathogenic fungus with a defined sexual cycle and well-developed molecular and genetic approaches. C. neoformans is predominantly haploid and has two mating types, MATa and MATα. Mating is known to be regulated by nutritional limitation and thought also to be regulated by pheromones. Previously, a portion of the MATα locus was cloned, and a presumptive pheromone gene, MFα1, was identified by its ability to induce conjugation tube-like filaments when introduced by transformation into MATa cells. Here, the ability of the MFα1 gene to induce these morphological changes in MATa cells was used as a phenotypic assay to perform a structure–function analysis of the gene. We show that the MFα1 open reading frame is required for the morphological response of MATa cells. We also find that the cysteine residue of the C-terminal CAAX motif is required for activity of the MFα1 pheromone. In addition, we use a reporter system to measure the expression levels of the MFα1 pheromone gene and find that two signals, nutrient starvation and the presence of factors secreted by mating partner cells, impinge on this promoter and regulate MFα1 expression. We identify a second pheromone gene, MFα2, and show phenotypically that this gene is also expressed. Finally, we have synthesized the MFα1 pheromone and show that only the predicted mature modified form of the α-factor peptide triggers morphological responses in MATa cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02213.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Interplay between three global regulatory proteins mediates oxygen regulation of the Escherichia coli cytochrome d oxidase (cydAB) operon (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The Escherichia coli cydAB operon, encoding the subunits of the high-affinity cytochrome d oxidase, is maximally transcribed in microaerobiosis as a result of the combined action of the oxygen-responsive regulators Fnr and ArcA. Here, we report that the histone-like protein H-NS is an aerobic repressor of cydAB expression. ArcA is shown to antagonize H-NS action to render cydAB expression insensitive to H-NS repression in anaerobiosis. The targets for H-NS-mediated aerobic repression are the four oxygen-regulated promoters, designated P1, P2, P3 and P4. H-NS control is the result of H-NS binding to an extended region within the cydAB promoter element, including sequences upstream from and overlapping the four regulated promoters. We propose a regulatory model in which oxygen control of cydAB transcription is mediated by three alternative protein–DNA complexes that are assembled sequentially on the promoter region as the cells are shifted from aerobic to microaerobic and to anaerobic conditions. According to this model, ArcA-P plays a central role in cydAB regulation by antagonizing H-NS repression of cydAB transcription when oxygen becomes limiting. This allows peak gene expression and subsequent repression by Fnr under fully anaerobic conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02215.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Modulation of KdpD phosphatase implicated in the physiological expression of the Kdp ATPase of Escherichia coli (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The KdpD sensor kinase and the KdpE response regulator control the expression of the kdpFABC operon, encoding the KdpFABC high-affinity K+ transport system of Escherichia coli. Low turgor pressure has been postulated to be the environmental stimulus to express KdpFABC. KdpD has autokinase, phosphotransferase and, like many sensor kinases, response regulator (phospho-KdpE) specific phosphatase activity. To determine which of these activities are altered in response to the environmental stimulus, we isolated and analysed six kdpD mutants that cause constitutive expression of KdpFABC. In three of the mutants, phosphatase activity was undetectable and, in two, phosphatase was reduced. Kinase activity was unaffected in four of the mutants, but elevated in one. In one mutant, a pseudorevertant of a kdpD null mutation, kinase and phosphatase were both reduced to 20% of the wild-type level. These findings suggest that initiation of signal transduction by KdpD is mediated by the inhibition of the phospho-KdpE-specific phosphatase activity of KdpD, leading to an accumulation of phospho-KdpE, which in turn activates the expression of the KdpFABC system. The data also suggest that levels of activity in vitro may differ from what occurs in vivo, because in vitro conditions cannot replicate those in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02219.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Genome organization and characterization of mycobacteriophage Bxb1 (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Mycobacteriophage Bxb1 is a temperate phage of Mycobacterium smegmatis. The morphology of Bxb1 particles is similar to that of mycobacteriophages L5 and D29, although Bxb1 differs from these phages in other respects. First, it is heteroimmune with L5 and efficiently forms plaques on an L5 lysogen. Secondly, it has a different host range and fails to infect slow-growing mycobacteria, using a receptor system that is apparently different from that of L5 and D29. Thirdly, it is the first mycobacteriophage to be described that forms a large prominent halo around plaques on a lawn of M. smegmatis. The sequence of the Bxb1 genome shows that it possesses a similar overall organization to the genomes of L5 and D29 and shares weak but detectable DNA sequence similarity to these phages within the structural genes. However, Bxb1 uses a different system of integration and excision, a repressor with different specificity to that of L5 and encodes a large number of novel gene products including several with enzymatic functions that could degrade or modify the mycobacterial cell wall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02183.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Group II introns in the bacterial world (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Group II introns are large catalytic RNA molecules that act as mobile genetic elements. They were initially identified in the organelle genomes of lower eukaryotes and plants, and it has been suggested that they are the progenitors of nuclear spliceosomal introns. Group II self-splicing introns were shown to be present in bacteria in 1993, since when the various bacterial genome sequencing projects have led to a significant increase in the number of group II intron sequences present in databases. However, few of these introns have been characterized, and most were identified on the basis of their intron-encoded protein (IEP), with little data available concerning their ribozyme/RNA structure. Their frequency in prokaryotes is also unknown. We attempt here to provide a first comprehensive review of bacterial group II introns based on recent genome sequencing data and mechanistic studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02197.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    A two-component system involving an HD-GYP domain protein links cell–cell signalling to pathogenicity gene expression in Xanthomonas campestris (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: The synthesis of extracellular enzymes and extracellular polysaccharide (EPS) in Xanthomonas campestris pv. campestris (Xcc) is regulated by a cluster of genes called rpf (for regulation of pathogenicity factors). Two of the genes, rpfF and rpfB, have previously been implicated in the synthesis of a diffusible regulatory molecule, DSF. Here, we describe a screen of transposon insertion mutants of Xcc that identified two DSF-overproducing strains. In each mutant, the gene disrupted is rpfC, which encodes a hybrid two-component regulatory protein in which the sensor and regulator domains are fused and which contains an additional C-terminal phosphorelay (HPt) domain. We show that rpfC is in an operon with rpfH and rpfG. The predicted protein RpfG has a regulatory input domain attached to a specialized version of an HD domain, previously suggested to function in signal transduction. The predicted protein RpfH is structurally related to the sensory input domain of RpfC. We show that RpfC and RpfG act positively to regulate the synthesis of extracellular enzymes and EPS, but that RpfC acts negatively to regulate the synthesis of DSF. We propose that RpfGHC is a signal transduction system that couples the synthesis of pathogenicity factors to sensing of environmental signals that may include DSF itself.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02196.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The abaA homologue of Penicillium marneffei participates in two developmental programmes: conidiation and dimorphic growth (2000)
    Oxford, UK : Blackwell Publishing Ltd
    Molecular microbiology 38 (2000), S. 0 
    Details
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Penicillium marneffei is the only known species of its genus that is dimorphic. At 25°C, P. marneffei exhibits true filamentous growth and undergoes asexual development producing spores borne on complex structures called conidiophores. At 37°C, P. marneffei undergoes a dimorphic transition to produce uninucleate yeast cells that divide by fission. We have cloned a homologue of the Aspergillus nidulans abaA gene encoding an ATTS/TEA DNA-binding domain transcriptional regulator and shown that it is involved in both these developmental programs. Targeted deletion of abaA blocks asexual development at 25°C before spore production, resulting in aberrant conidiophores with reiterated terminal cells. At 37°C, the abaA deletion strain fails to switch correctly from multinucleate filamentous to uninucleate yeast cells. Both the transitional hyphal cells, which produce the yeast cells, and the yeast cells themselves contain multiple nuclei. Expression of the abaA gene is activated during both conidiation and the hyphal–yeast switch. Interestingly, the abaA gene of the filamentous monomorphic fungus A. nidulans can complement both conidiation and dimorphic switching defects in the P. marneffei abaA mutant. In addition, ectopic overexpression of abaA results in anucleate yeast cells and multinucleate vegetative filamentous cells. These data suggest that abaA regulates cell cycle events and morphogenesis in two distinct developmental programmes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2958.2000.02202.x
    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...