The alternative sigma factor σ B in Staphylococcus aureus : regulation of the sigB operon in response to growth phase and heat shock

1997 ◽  
Vol 167 (2-3) ◽  
pp. 151-159 ◽  
Author(s):  
I. Kullik ◽  
P. Giachino
Keyword(s):  
Staphylococcus Aureus ◽  
Heat Shock ◽  
Growth Phase ◽  
Sigma Factor ◽  
Alternative Sigma Factor

Activation of the alternative sigma factor SigB of Staphylococcus aureus following internalization by epithelial cells – An in vivo proteomics perspective

2014 ◽  
Vol 304 (2) ◽  
pp. 177-187 ◽  
Author(s):  
Henrike Pförtner ◽  
Marc S. Burian ◽  
Stephan Michalik ◽  
Maren Depke ◽  
Petra Hildebrandt ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Epithelial Cells ◽  
Sigma Factor ◽  
Alternative Sigma Factor

scholarly journals CspA Regulates Pigment Production in Staphylococcus aureus through a SigB-Dependent Mechanism

2005 ◽  
Vol 187 (23) ◽  
pp. 8181-8184 ◽  
Author(s):  
Samuel Katzif ◽  
Eun-Hee Lee ◽  
Anthony B. Law ◽  
Yih-Ling Tzeng ◽  
William M. Shafer
Keyword(s):  
Staphylococcus Aureus ◽  
Sigma Factor ◽  
Cold Shock ◽  
Pigment Production ◽  
Cold Shock Protein ◽  
Alternative Sigma Factor ◽  
Expression Of Genes ◽  
Maximal Production ◽  
Dependent Mechanism

ABSTRACT We report that the cold shock protein CspA of Staphylococcus aureus is required for maximal production of pigment. Results from transcriptional studies revealed that loss of CspA resulted in decreased expression of genes needed for the biosynthesis of 4,4′-diaponeurosporene and the alternative sigma factor SigB.

scholarly journals Robust Heat Shock Response in Chlamydia Lacking a Typical Heat Shock Sigma Factor

2022 ◽  
Vol 12 ◽  
Author(s):  
Yehong Huang ◽  
Wurihan Wurihan ◽  
Bin Lu ◽  
Yi Zou ◽  
Yuxuan Wang ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Heat Shock Response ◽  
Sigma Factor ◽  
Target Genes ◽  
Sigma Factors ◽  
Survival Strategies ◽  
Alternative Sigma Factor ◽  
Metabolism Enzymes ◽  
Shock Response

Cells reprogram their transcriptome in response to stress, such as heat shock. In free-living bacteria, the transcriptomic reprogramming is mediated by increased DNA-binding activity of heat shock sigma factors and activation of genes normally repressed by heat-induced transcription factors. In this study, we performed transcriptomic analyses to investigate heat shock response in the obligate intracellular bacterium Chlamydia trachomatis, whose genome encodes only three sigma factors and a single heat-induced transcription factor. Nearly one-third of C. trachomatis genes showed statistically significant (≥1.5-fold) expression changes 30 min after shifting from 37 to 45°C. Notably, chromosomal genes encoding chaperones, energy metabolism enzymes, type III secretion proteins, as well as most plasmid-encoded genes, were differentially upregulated. In contrast, genes with functions in protein synthesis were disproportionately downregulated. These findings suggest that facilitating protein folding, increasing energy production, manipulating host activities, upregulating plasmid-encoded gene expression, and decreasing general protein synthesis helps facilitate C. trachomatis survival under stress. In addition to relieving negative regulation by the heat-inducible transcriptional repressor HrcA, heat shock upregulated the chlamydial primary sigma factor σ66 and an alternative sigma factor σ28. Interestingly, we show for the first time that heat shock downregulates the other alternative sigma factor σ54 in a bacterium. Downregulation of σ54 was accompanied by increased expression of the σ54 RNA polymerase activator AtoC, thus suggesting a unique regulatory mechanism for reestablishing normal expression of select σ54 target genes. Taken together, our findings reveal that C. trachomatis utilizes multiple novel survival strategies to cope with environmental stress and even to replicate. Future strategies that can specifically target and disrupt Chlamydia’s heat shock response will likely be of therapeutic value.

scholarly journals The Staphylococcus aureus rsbW(orf159) Gene Encodes an Anti-Sigma Factor of SigB

1999 ◽  
Vol 181 (9) ◽  
pp. 2846-2851 ◽  
Author(s):  
Eishi Miyazaki ◽  
Jong-Min Chen ◽  
Chiew Ko ◽  
William R. Bishai
Keyword(s):  
Staphylococcus Aureus ◽  
Stress Responses ◽  
Sigma Factor ◽  
Specific Binding ◽  
In Vitro Transcription ◽  
Alternative Sigma Factor ◽  
Consensus Sequences ◽  
Its Gene ◽  
Genes Encoding

ABSTRACT SigB, a newly discovered alternative sigma factor ofStaphylococcus aureus, has been shown to play an important role in stress responses and the regulation of virulence factors. ThersbW (orf159) gene is immediately upstream ofsigB. Its gene product is homologous to Bacillus subtilis RsbW which under appropriate conditions binds toB. subtilis SigB and functions as an anti-sigma factor or negative posttranslational regulator. To define the function ofS. aureus RsbW, both the S. aureus SigB and RsbW proteins were expressed in Escherichia coli and purified. Cross-linking experiments with these purified proteins revealed that RsbW was capable of specific binding to SigB. In an in vitro transcription runoff assay, RsbW prevented SigB-directed transcription from the sar P3 promoter, a known SigB-dependent promoter, and the inhibitory activity of RsbW was found to be concentration dependent. We also identified SigB promoter consensus sequences upstream of the genes encoding alkaline shock protein 23 and coagulase and have demonstrated SigB and RsbW dependence for the promoters in vitro. These results show that RsbW is a protein sequestering anti-sigma factor of S. aureus SigB and suggest that SigB activity in S. aureus is regulated posttranslationally.

scholarly journals Salt-Induced Stress Stimulates a Lipoteichoic Acid-Specific Three-Component Glycosylation System inStaphylococcus aureus

2018 ◽  
Vol 200 (12) ◽  
Author(s):  
Kelvin Kho ◽  
Timothy C. Meredith
Keyword(s):  
Staphylococcus Aureus ◽  
Sigma Factor ◽  
Cell Envelope ◽  
Normal Growth ◽  
Lipoteichoic Acid ◽  
Growth Conditions ◽  
Growth Media ◽  
Alternative Sigma Factor ◽  
Content Type

ABSTRACTLipoteichoic acid (LTA) inStaphylococcus aureusis a poly-glycerophosphate polymer anchored to the outer surface of the cell membrane. LTA has numerous roles in cell envelope physiology, including regulating cell autolysis, coordinating cell division, and adapting to environmental growth conditions. LTA is often further modified with substituents, includingd-alanine and glycosyl groups, to alter cellular function. While the genetic determinants ofd-alanylation have been largely defined, the route of LTA glycosylation and its role in cell envelope physiology have remained unknown, in part due to the low levels of basal LTA glycosylation inS. aureus. We demonstrate here thatS. aureusutilizes a membrane-associated three-component glycosylation system composed of an undecaprenol (Und)N-acetylglucosamine (GlcNAc) charging enzyme (CsbB; SAOUHSC_00713), a putative flippase to transport loaded substrate to the outside surface of the cell (GtcA; SAOUHSC_02722), and finally an LTA-specific glycosyltransferase that adds α-GlcNAc moieties to LTA (YfhO; SAOUHSC_01213). We demonstrate that this system is specific for LTA with no cross recognition of the structurally similar polyribitol phosphate containing wall teichoic acids. We show that while wild-typeS. aureusLTA has only a trace of GlcNAcylated LTA under normal growth conditions, amounts are raised upon either overexpressing CsbB, reducing endogenousd-alanylation activity, expressing the cell envelope stress responsive alternative sigma factor SigB, or by exposure to environmental stress-inducing culture conditions, including growth media containing high levels of sodium chloride.IMPORTANCEThe role of glycosylation in the structure and function ofStaphylococcus aureuslipoteichoic acid (LTA) is largely unknown. By defining key components of the LTA three-component glycosylation pathway and uncovering stress-induced regulation by the alternative sigma factor SigB, the role ofN-acetylglucosamine tailoring during adaptation to environmental stresses can now be elucidated. As thedltand glycosylation pathways compete for the same sites on LTA and induction of glycosylation results in decreasedd-alanylation, the interplay between the two modification systems holds implications for resistance to antibiotics and antimicrobial peptides.

scholarly journals Role of RsbU in Controlling SigB Activity in Staphylococcus aureus following Alkaline Stress

2009 ◽  
Vol 191 (8) ◽  
pp. 2561-2573 ◽  
Author(s):  
Jan Pané-Farré ◽  
Beate Jonas ◽  
Steven W. Hardwick ◽  
Katrin Gronau ◽  
Richard J. Lewis ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
High Activity ◽  
Protein Phosphatase ◽  
Sigma Factor ◽  
Alternative Sigma Factor ◽  
Alkaline Stress ◽  
High Molecular Weight Complex ◽  
Terminal Domain ◽  
Related Organism

ABSTRACT SigB is an alternative sigma factor that controls a large regulon in Staphylococcus aureus. Activation of SigB requires RsbU, a protein phosphatase 2C (PP2C)-type phosphatase. In a closely related organism, Bacillus subtilis, RsbU activity is stimulated upon interaction with RsbT, a kinase, which following an activating stimulus switches from a 25S high-molecular-weight complex, the stressosome, to the N-terminal domain of RsbU. Active RsbU dephosporylates RsbV and thereby triggers the release of SigB from its inhibitory complex with RsbW. While RsbU, RsbV, RsbW, and SigB are conserved in S. aureus, proteins similar to RsbT and the components of the stressosome are not, raising the question of how RsbU activity and hence SigB activity are controlled in S. aureus. We found that in contrast to the case in B. subtilis, the induced expression of RsbU was sufficient to stimulate SigB-dependent transcription in S. aureus. However, activation of SigB-dependent transcription following alkaline stress did not lead to a clear accumulation of SigB and its regulators RsbV and RsbW or to a change in the RsbV/RsbV-P ratio in S. aureus. When expressed in B. subtilis, the S. aureus RsbU displayed a high activity even in the absence of an inducing stimulus. This high activity could be transferred to the PP2C domain of the B. subtilis RsbU protein by a fusion to the N-terminal domain of the S. aureus RsbU. Collectively, the data suggest that the activity of the S. aureus RsbU and hence SigB may be subjected to different regulation in comparison to that in B. subtilis.

Sign in / Sign up

Export Citation Format

Share Document