Abstract:
:It is now well established that the sigma S subunit of RNA polymerase is a master regulator in a complex regulatory network that governs the expression of many stationary-phase-inducible genes in Escherichia coli. In this review, more recent findings will be summarized that demonstrate that sigma S also acts as a global regulator for the osmotic control of gene expression, and actually does so in exponentially growing cells. Thus, many sigma S-dependent genes are induced during entry into stationary phase as well as in response to osmotic upshift. K+ glutamate, which accumulates in hyperosmotically stressed cells, seems to specifically stimulate the activity of sigma S-containing RNA polymerase at sigma S-dependent promoters. Moreover, osmotic upshift results in an elevated cellular sigma S level similar to that observed in stationary-phase cells. This increase is the result of a stimulation of rpoS translation as well as an inhibition of the turnover of sigma S, which in exponentially growing non-stressed cells is a highly unstable protein. Whereas the RNA-binding protein HF-I, previously known as a host factor for the replication of phage Q beta RNA, is essential for rpoS translation, the recently discovered response regulator RssB, and ClpXP protease, have been shown to be required for sigma S degradation. The finding that the histone-like protein H-NS is also involved in the control of rpoS translation and sigma S turnover, sheds new light on the function of this protein in osmoregulation. Finally, preliminary evidence suggests that additional stresses, such as heat shock and acid shock, also result in increased cellular sigma S levels in exponentially growing cells. Taken together, sigma S function is clearly not confined to stationary phase. Rather, sigma S may be regarded as a sigma factor associated with general stress conditions.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Hengge-Aronis Rdoi
10.1046/j.1365-2958.1996.511405.xsubject
Has Abstractpub_date
1996-09-01 00:00:00pages
887-93issue
5eissn
0950-382Xissn
1365-2958journal_volume
21pub_type
杂志文章,评审abstract::Cells invest a significant amount of their energy synthesizing proteins, and a large portion of the energy expenditure goes into making ribosomes, the RNA-protein machines at the centre of translation. When ribosomes are damaged in a cell, i.e. during stressful conditions, cells must first recognize the damage and the...
journal_title:Molecular microbiology
pub_type: 评论,杂志文章
doi:10.1111/j.1365-2958.2009.07017.x
更新日期:2010-02-01 00:00:00
abstract::DNA processing reactions often involve multiple components acting in concert to achieve the desired outcome. However, it is usually difficult to know how the components communicate and cooperate to orchestrate an ordered series of events. We address this question in the context of the Tn 10 transposition reaction, in ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05432.x
更新日期:2006-12-01 00:00:00
abstract::Micrococcus luteus secretes a small protein called Rpf, which has autocrine and paracrine signalling functions and is required for the resuscitation of dormant cells. Originally isolated from the supernatant of actively growing cultures, Rpf was also detected on the surface of actively growing bacteria. Most molecules...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03183.x
更新日期:2002-11-01 00:00:00
abstract::Multimer formation reduces plasmid copy number and is an established cause of segregational instability. Nevertheless, it is difficult to rationalize observations that low levels of dimers can cause severe instability, if we assume they are distributed evenly in cell populations. We report here that dimer distribution...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1993.tb01648.x
更新日期:1993-06-01 00:00:00
abstract::A reputed iron-responsive region, which contains multiple nuclear protein-binding DNA sequences, was shown previously to regulate iron-inducible transcription of the ap65-1 gene in the protozoan pathogen, Trichomonas vaginalis. These DNA sequences include two overlapping MYB recognition elements (MRE-1/MRE-2r) and thr...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04088.x
更新日期:2004-06-01 00:00:00
abstract::Burkholderia mallei, the aetiologic agent of glanders, causes a variety of illnesses in animals and humans ranging from occult infections to acute fulminating septicaemias. To better understand the role of lipopolysaccharide (LPS) in the pathogenesis of these diseases, studies were initiated to characterize the struct...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05519.x
更新日期:2007-01-01 00:00:00
abstract::Members of the bacterial genus Brucella are facultative intracellular pathogens that reside predominantly within membrane-bound compartments within two host cell types, macrophages and placental trophoblasts. Within macrophages, the brucellae route themselves to an intracellular compartment that is favourable for surv...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.2004.04017.x
更新日期:2004-05-01 00:00:00
abstract::Candida albicans is the single, most frequently isolated human fungal pathogen. As with most fungal pathogens, the factors which contribute to pathogenesis in C. albicans are not known, despite more than a decade of molecular genetic analysis. Candida albicans was thought to be asexual until the discovery of the MTL l...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03263.x
更新日期:2002-12-01 00:00:00
abstract::The complete nucleotide sequence of the gene for a cell-surface protein antigen (PAc) of Streptococcus mutans MT8148 (serotype c) was determined. The pac gene consisted of 4695 bp and coded for a 170773D protein. The pac gene product contained a putative 38 amino acid signal peptide, resulting in a 166817D mature prot...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1989.tb00215.x
更新日期:1989-05-01 00:00:00
abstract::Dynamic oscillation of the Min system in Escherichia coli determines the placement of the division plane at the midcell. In addition to stimulating MinD ATPase activity, we report here that MinE can directly interact with the membrane and this interaction contributes to the proper MinDE localization and dynamics. The ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2009.07006.x
更新日期:2010-01-01 00:00:00
abstract::Beta-oxidation (beta-ox) occurs exclusively in the peroxisomes of Saccharomyces cerevisiae and other yeasts, leading to the supposition that fungi lack mitochondrial beta-ox. Here we present unequivocal evidence that the filamentous fungus Aspergillus nidulans houses both peroxisomal and mitochondrial beta-ox. While g...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04340.x
更新日期:2004-12-01 00:00:00
abstract::Thymidylate, an essential building block of DNA, is synthesized either from deoxyuridylate by thymidylate synthase (TS) or thymidine (dT) by thymidine kinase (TK). Thymidylate kinase (TMPK) phosphorylates dTMP to dTTP. Thymidine phosphorylase (TP) catalyses reversible phosphorolysis of dT. Using transposon mutagenesis...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07298.x
更新日期:2010-09-01 00:00:00
abstract::Francisella tularensis are the causative agent of the zoonotic disease, tularaemia. Among four F. tularensis subspecies, ssp. novicida (F. novicida) is pathogenic only for immunocompromised individuals, while all four subspecies are pathogenic for mice. This study utilized proteomic and bioinformatic approaches to ide...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05365.x
更新日期:2006-10-01 00:00:00
abstract::The bioluminescent marine bacterium Vibrio harveyi controls light production (lux) by an elaborate quorum-sensing circuit. V. harveyi produces and responds to two different autoinducer signals (AI-1 and AI-2) to modulate the luciferase structural operon (luxCDABEGH) in response to changes in cell-population density. U...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.01913.x
更新日期:2000-05-01 00:00:00
abstract::The overall transcription of DNA has previously been demonstrated to proceed at extremely high levels of accuracy. We review the evidence that the process of transcription is subject to proof-reading in the Hopfield sense. In addition, we speculate that the proof-reading activity associated with transcription is subje...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.1991.tb01872.x
更新日期:1991-05-01 00:00:00
abstract::Clp ATPases, which include the ubiquitous HSP100 family, are classified according to their structural features and sequence similarities. During the course of the Bacillus subtilis genome sequencing project, we identified a gene encoding a new member of the HSP100 family. We designated this protein ClpE, as it is the ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1999.01374.x
更新日期:1999-05-01 00:00:00
abstract::Genotoxic agents from endogenous and exogenous sources cause double-strand breaks (DSBs) in chromosomal DNA. Given the threat these lesions pose to viability, it is not surprising that multiple, conserved mechanisms exist for their detection, processing and repair. Previous studies have established both functional non...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07462.x
更新日期:2011-01-01 00:00:00
abstract::Pseudomonas aeruginosa, a Gram-negative bacterium, is a significant opportunistic pathogen associated with skin and soft tissue infections, nosocomial pneumonia and sepsis. In addition, it can chronically colonize the lungs of cystic fibrosis (CF) patients. Overproduction of the exopolysaccharide called alginate provi...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.2012.08049.x
更新日期:2012-05-01 00:00:00
abstract::Phytopathogenic bacteria possess a large number of genes that allow them to grow and cause disease on plants. Many of these genes should be induced when the bacteria come in contact with plant tissue. We used a modified in vivo expression technology (IVET) approach to identify genes from the plant pathogen Pseudomonas...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.02877.x
更新日期:2002-04-01 00:00:00
abstract::Prior to the discovery of a minimal ATP-dependent DNA ligase in Haemophilus influenzae, bacteria were thought to only possess a NAD-dependent ligase, which was involved in sealing of Okazaki fragments. We now know that a diverse range of bacterial species possess up to six of these accessory bacterial ATP-dependent DN...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13229
更新日期:2016-01-01 00:00:00
abstract::In the yeast Saccharomyces cerevisiae, PKA and Sch9 exert similar physiological roles in response to nutrient availability. However, their functional redundancy complicates to distinguish properly the target genes for both kinases. In this article, we analysed different phenotypic read-outs. The data unequivocally sho...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04429.x
更新日期:2005-02-01 00:00:00
abstract::We have isolated and sequenced a set of deletions stimulated by DNA palindromes in Escherichia coli. All of the deletions are asymmetric with respect to the parental sequence and have occurred at short direct repeats. This is consistent with deletion by strand slippage during DNA replication. The orientation of the as...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00831.x
更新日期:1998-05-01 00:00:00
abstract::Entamoeba histolytica cells secrete electron-dense granules (EDGs) that have collagenase activity. To study the possible involvement of calmodulin (CaM) on EDG secretion, the effect of several CaM antagonists (TFP, R24571, W-7, W-5, dibucaine and DL-propranolol) was tested on this cellular function. Except for W-5 and...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1991.tb01919.x
更新日期:1991-07-01 00:00:00
abstract::Superoxide dismutase, catalase, glutathione peroxidase and peroxiredoxins form an antioxidant network protecting cells against reactive oxygen species (ROS). Catalase is a potent H2O2-detoxifying enzyme, which is unexpectedly absent in some members of the Kinetoplastida and Apicomplexa, but present in Toxoplasma gondi...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2003.03823.x
更新日期:2004-01-01 00:00:00
abstract::The PII protein has been considered pivotal to the dual cascade regulating ammonia assimilation through glutamine synthetase activity. Here we show that PII, encoded by the glnB gene, is not always essential; for instance upon ammonia deprivation of a glnB deletion strain, glutamine synthetase can be deadenylylated as...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1996.6281349.x
更新日期:1996-07-01 00:00:00
abstract::Cell cycle transitions are often triggered by the proteolysis of key regulatory proteins. In Caulobacter crescentus, the G1-S transition involves the degradation of an essential DNA-binding response regulator, CtrA, by the ClpXP protease. Here, we show that another critical cell cycle regulator, SciP, is also degraded...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12166
更新日期:2013-03-01 00:00:00
abstract::Pseudomonas syringae pv. tomato (Pst) strain DC3000 infects the model plants Arabidopsis thaliana and tomato, causing disease symptoms characterized by necrotic lesions surrounded by chlorosis. One mechanism used by Pst DC3000 to infect host plants is the type III protein secretion system, which is thought to deliver ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.02964.x
更新日期:2002-09-01 00:00:00
abstract::Bacteria attach to their appropriate environmental niche by using adhesins. To maximize their contact with the environment, adhesins are often present on the ends of long hairlike structures called pili. Recently, attention has focused on pili of Gram-positive bacteria because they may be vaccine candidates in importa...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.2006.05279.x
更新日期:2006-10-01 00:00:00
abstract::Bacterial autotransporters consist of an N-terminal 'passenger domain' that is transported into the extracellular space by an unknown mechanism and a C-terminal 'beta-domain' that forms a beta-barrel in the outer membrane. Recent studies have revealed that fully assembled autotransporters have an unusual architecture ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2007.06048.x
更新日期:2008-01-01 00:00:00
abstract::The ability of Salmonella typhimurium to survive and replicate within murine macrophages is dependent on a low phagosomal pH. This requirement for an acidic vacuole suggests that low pH is an important environmental stimulus for the transcription of genes necessary for intracellular survival. To study the behaviour of...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1996.00120.x
更新日期:1996-10-01 00:00:00