The staphylococcal respiratory response regulator SrrAB induces ica gene transcription and polysaccharide intercellular adhesin expression, protecting Staphylococcus aureus from neutrophil killing under anaerobic growth conditions

We previously described a transposon mutant in Staphylococcus aureus strain SH1000 that exhibited reduced susceptibility to cationic thrombin-induced platelet microbicidal proteins (tPMPs). The transposon insertion site was mapped to the gene snoD, the staphylococcal nuo orthologue. Hence, further studies have been performed to understand how this mutation impacts susceptibility to tPMP, by comparing proteomics profiling and membrane lipid analyses of the parent vs. mutant strains. Surprisingly, the mutant showed differential regulation of only a single protein when cultivated aerobically (FadB), and only a small number of proteins under anaerobic growth conditions (AdhE, DapE, Ddh, Ald1, IlvA1, AgrA, Rot, SA2366, and SA2367). Corresponding to FadB impact on lipid remodeling, membrane fatty acid analyses showed that the snoD mutant contained more short chain anteiso-, but fewer short chain iso-branched chain fatty acids under both aerobic and anaerobic conditions vs. the parental strain. Based upon these proteomic and membrane compositional data, a hypothetical “network” model was developed to explain the impact of the snoD mutation upon tPMP susceptibility.

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The sensor kinase DcuS of Escherichia coli: two stimulus input sites and a merged signal pathway in the DctA/DcuS sensor unit

Biological Chemistry ◽

10.1515/hsz-2012-0229 ◽

2012 ◽

Vol 393 (11) ◽

pp. 1291-1297 ◽

Cited By ~ 11

Author(s):

Julian Witan ◽

Christian Monzel ◽

Patrick D. Scheu ◽

Gottfried Unden

Keyword(s):

Escherichia Coli ◽

Target Genes ◽

Response Regulator ◽

Growth Conditions ◽

Kinase Domain ◽

Anaerobic Growth ◽

Phosphoryl Transfer ◽

Sensor Kinase ◽

Signal Transfer ◽

Sensor Unit

Abstract The membrane-integral sensor kinase DcuS of Escherichia coli consists of a periplasmically located sensory PASP domain, transmembrane helices TM1 and TM2, a cytoplasmic PASC domain and the kinase domain. Stimulus (C4-dicarboxylate) binding at PASP is required to stimulate phosphorylation of the kinase domain, resulting in phosphoryl transfer to the response regulator DcuR. PASC functions as a signaling device or a relay in signal transfer from TM2 to the kinase. Phosphorylated DcuR induces the expression of the target genes. Sensing by DcuS requires the presence of the C4-dicarboxylate transporter DctA during aerobic growth. DctA forms a sensor unit with DcuS, and a short C-terminal sequence of DctA forming the putative helix 8b is required for interaction with DcuS. Helix 8b contains a LDXXXLXXXL motif that is essential for function and interaction. DcuS requires the PASC domain for signal perception from DctA. Thus, DcuS and DctA form a DctA/DcuS sensory unit, and DcuS perceives stimuli from two different sites (PASP and DctA). The signal transfer pathways are supposed to merge at PASC. The fumarate/succinate antiporter DcuB takes over the role as a co-sensor of DcuS under anaerobic growth conditions.

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Global Gene Expression in Staphylococcus aureus Biofilms

Journal of Bacteriology ◽

10.1128/jb.186.14.4665-4684.2004 ◽

2004 ◽

Vol 186 (14) ◽

pp. 4665-4684 ◽

Cited By ~ 385

Author(s):

Karen E. Beenken ◽

Paul M. Dunman ◽

Fionnuala McAleese ◽

Daphne Macapagal ◽

Ellen Murphy ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Adaptive Response ◽

Biofilm Formation ◽

Global Gene Expression ◽

Growth Conditions ◽

Anaerobic Growth ◽

Over Expression ◽

Custom Made

ABSTRACT We previously demonstrated that mutation of the staphylococcal accessory regulator (sarA) in a clinical isolate of Staphylococcus aureus (UAMS-1) results in an impaired capacity to form a biofilm in vitro (K. E. Beenken, J. S. Blevins, and M. S. Smeltzer, Infect. Immun. 71:4206-4211, 2003). In this report, we used a murine model of catheter-based biofilm formation to demonstrate that a UAMS-1 sarA mutant also has a reduced capacity to form a biofilm in vivo. Surprisingly, mutation of the UAMS-1 ica locus had little impact on biofilm formation in vitro or in vivo. In an effort to identify additional loci that might be relevant to biofilm formation and/or the adaptive response required for persistence of S. aureus within a biofilm, we isolated total cellular RNA from UAMS-1 harvested from a biofilm grown in a flow cell and compared the transcriptional profile of this RNA to RNA isolated from both exponential- and stationary-phase planktonic cultures. Comparisons were done using a custom-made Affymetrix GeneChip representing the genomic complement of six strains of S. aureus (COL, N315, Mu50, NCTC 8325, EMRSA-16 [strain 252], and MSSA-476). The results confirm that the sessile lifestyle associated with persistence within a biofilm is distinct by comparison to the lifestyles of both the exponential and postexponential phases of planktonic culture. Indeed, we identified 48 genes in which expression was induced at least twofold in biofilms over expression under both planktonic conditions. Similarly, we identified 84 genes in which expression was repressed by a factor of at least 2 compared to expression under both planktonic conditions. A primary theme that emerged from the analysis of these genes is that persistence within a biofilm requires an adaptive response that limits the deleterious effects of the reduced pH associated with anaerobic growth conditions.

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Role and regulation of the superoxide dismutases of Staphylococcus aureus

Microbiology ◽

10.1099/mic.0.26353-0 ◽

2003 ◽

Vol 149 (10) ◽

pp. 2749-2758 ◽

Cited By ~ 132

Author(s):

Michail H. Karavolos ◽

Malcolm J. Horsburgh ◽

Eileen Ingham ◽

Simon J. Foster

Keyword(s):

Staphylococcus Aureus ◽

Gene Transcription ◽

Growth Phase ◽

Parental Strain ◽

Growth Conditions ◽

Superoxide Dismutases ◽

Sod Activity ◽

Host Infection ◽

Transcriptional Start Sites ◽

Superoxide Scavenger

Staphylococcus aureus has two superoxide dismutases (SODs), encoded by the sodA and sodM genes, which inactivate harmful superoxide radicals () encountered during host infection or generated from aerobic metabolism. The transcriptional start sites have been mapped and expression analysis on reporter fusions in both genes has been carried out. Under standard growth conditions, manganese (Mn), a mineral superoxide scavenger, elevated total SOD activity but had no effect on the transcription of either gene. Transcription of sodA and sodM was most strongly induced by either internally or externally generated , respectively. Sensitivity to internally generated was linked with SodA deficiency. Mn supplementation completely rescued a sodA mutant when challenged by internally generated , and this was growth-phase-dependent. Sensitivity to externally generated stress was only observed in a sodA sodM mutant and was Mn-independent. In a mouse abscess model of infection, isogenic sodA, sodM and sodA sodM mutants had reduced virulence compared to the parental strain, showing the importance of the enzymic scavenging system for the survival of the pathogen.

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Evolutionary rewiring: a modified prokaryotic gene-regulatory pathway in chloroplasts

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0260 ◽

2013 ◽

Vol 368 (1622) ◽

pp. 20120260 ◽

Cited By ~ 25

Author(s):

Sujith Puthiyaveetil ◽

Iskander M. Ibrahim ◽

John F. Allen

Keyword(s):

Green Algae ◽

Gene Transcription ◽

Response Regulator ◽

Regulatory System ◽

Photosynthetic Electron Transport ◽

Sensor Kinase ◽

Ps I ◽

Component Systems ◽

Two Component Systems ◽

Gene Regulatory

Photosynthetic electron transport regulates chloroplast gene transcription through the action of a bacterial-type sensor kinase known as chloroplast sensor kinase (CSK). CSK represses photosystem I (PS I) gene transcription in PS I light and thus initiates photosystem stoichiometry adjustment. In cyanobacteria and in non-green algae, CSK homologues co-exist with their response regulator partners in canonical bacterial two-component systems. In green algae and plants, however, no response regulator partner of CSK is found. Yeast two-hybrid analysis has revealed interaction of CSK with sigma factor 1 (SIG1) of chloroplast RNA polymerase. Here we present further evidence for the interaction between CSK and SIG1. We also show that CSK interacts with quinone. Arabidopsis SIG1 becomes phosphorylated in PS I light, which then specifically represses transcription of PS I genes. In view of the identical signalling properties of CSK and SIG1 and of their interactions, we suggest that CSK is a SIG1 kinase. We propose that the selective repression of PS I genes arises from the operation of a gene-regulatory phosphoswitch in SIG1. The CSK-SIG1 system represents a novel, rewired chloroplast-signalling pathway created by evolutionary tinkering. This regulatory system supports a proposal for the selection pressure behind the evolutionary stasis of chloroplast genes.

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Anaerobic Conditions Induce Expression of Polysaccharide Intercellular Adhesin in Staphylococcus aureus and Staphylococcus epidermidis

Infection and Immunity ◽

10.1128/iai.69.6.4079-4085.2001 ◽

2001 ◽

Vol 69 (6) ◽

pp. 4079-4085 ◽

Cited By ~ 222

Author(s):

Sarah E. Cramton ◽

Martina Ulrich ◽

Friedrich Götz ◽

Gerd Döring

Keyword(s):

Staphylococcus Aureus ◽

Staphylococcus Epidermidis ◽

Biofilm Formation ◽

Extracellular Polysaccharide ◽

Growth Conditions ◽

Anaerobic Conditions ◽

Anaerobic Environment ◽

Specific Mrna

ABSTRACT Products of the intercellular adhesion (ica) operon in Staphylococcus aureus and Staphylococcus epidermidis synthesize a linear β-1,6-linked glucosaminylglycan. This extracellular polysaccharide mediates bacterial cell-cell adhesion and is required for biofilm formation, which is thought to increase the virulence of both pathogens in association with prosthetic biomedical implants. The environmental signal(s) that triggers ica gene product and polysaccharide expression is unknown. Here we demonstrate that anaerobic in vitro growth conditions lead to increased polysaccharide expression in both S. aureus and S. epidermidis, although the regulation is less stringent inS. epidermidis. Anaerobiosis also dramatically stimulates ica-specific mRNA expression inica- and polysaccharide-positive strains of both S. aureus and S. epidermidis.These data suggest a mechanism whereby ica gene expression and polysaccharide production may act as a virulence factor in an anaerobic environment in vivo.

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Acute Peritonitis Caused by Propionibacterium Acnes in a Peritoneal Dialysis Patient

BANTAO Journal ◽

10.1515/bj-2017-0008 ◽

2017 ◽

Vol 15 (1) ◽

pp. 33-34

Author(s):

Nikolina Basic-Jukic ◽

Vesna Furic-Cunko ◽

Ivana Juric ◽

Lea Katalinic ◽

Ana Rukavina ◽

...

Keyword(s):

Peritoneal Dialysis ◽

Human Skin ◽

Dialysis Patient ◽

Propionibacterium Acnes ◽

Peritoneal Dialysis Patient ◽

Growth Conditions ◽

Anaerobic Growth ◽

Gram Positive ◽

Acute Peritonitis ◽

Clinical Conditions

AbstractPropionibacterium acnes is a gram-positive human skin commensal that is involved in the pathogenesis of acne and prefers anaerobic growth conditions. It has been considered as a low virulence pathogen in different clinical conditions. We present the case of acute peritonitis caused by Propionibacterium acnes in a peritoneal dialysis patient.

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