scholarly journals Dual Roles of FmtA in Staphylococcus aureus Cell Wall Biosynthesis and Autolysis

2012 ◽  
Vol 56 (7) ◽  
pp. 3797-3805 ◽  
Author(s):  
Aneela Qamar ◽  
Dasantila Golemi-Kotra
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Wall Stress ◽  
Microscopy Study ◽  
Dual Roles ◽  
Content Type ◽  
Teichoic Acids ◽  
Low Concentrations ◽  
High Concentrations ◽  
Wall Teichoic Acids

ABSTRACTThefmtAgene is a member of theStaphylococcus aureuscore cell wall stimulon. The FmtA protein interacts with β-lactams through formation of covalent species. Here, we show that FmtA has weakd-Ala-d-Ala-carboxypeptidase activity and is capable of covalently incorporating C14-Gly into cell walls. The fluorescence microscopy study showed that the protein is localized to the cell division septum. Furthermore, we show that wall teichoic acids interact specifically with FmtA and mediate recruitment of FmtA to theS. aureuscell wall. Subjection ofS. aureusto FmtA concentrations of 0.1 μM or less induces autolysis and biofilm production. This effect requires the presence of wall teichoic acids. At FmtA concentrations greater than 0.2 μM, autolysis and biofilm formation inS. aureusare repressed and growth is enhanced. Our findings indicate dual roles of FmtA inS. aureusgrowth, whereby at low concentrations, FmtA may modulate the activity of the major autolysin (AtlA) ofS. aureusand, at high concentrations, may participate in synthesis of cell wall peptidoglycan. These two roles of FmtA may reflect dual functions of FmtA in the absence and presence of cell wall stress, respectively.

scholarly journals Biosynthesis of the Unique Wall Teichoic Acid of Staphylococcus aureus Lineage ST395

mBio ◽  
2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Volker Winstel ◽  
Patricia Sanchez-Carballo ◽  
Otto Holst ◽  
Guoqing Xia ◽  
Andreas Peschel
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Biosynthesis Pathway ◽  
Glycerol Phosphate ◽  
Coagulase Negative Staphylococci ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Wall Teichoic Acids

ABSTRACT The major clonal lineages of the human pathogen Staphylococcus aureus produce cell wall-anchored anionic poly-ribitol-phosphate (RboP) wall teichoic acids (WTA) substituted with d-Alanine and N-acetyl-d-glucosamine. The phylogenetically isolated S. aureus ST395 lineage has recently been found to produce a unique poly-glycerol-phosphate (GroP) WTA glycosylated with N-acetyl-d-galactosamine (GalNAc). ST395 clones bear putative WTA biosynthesis genes on a novel genetic element probably acquired from coagulase-negative staphylococci (CoNS). We elucidated the ST395 WTA biosynthesis pathway and identified three novel WTA biosynthetic genes, including those encoding an α-O-GalNAc transferase TagN, a nucleotide sugar epimerase TagV probably required for generation of the activated sugar donor substrate for TagN, and an unusually short GroP WTA polymerase TagF. By using a panel of mutants derived from ST395, the GalNAc residues carried by GroP WTA were found to be required for infection by the ST395-specific bacteriophage Φ187 and to play a crucial role in horizontal gene transfer of S. aureus pathogenicity islands (SaPIs). Notably, ectopic expression of ST395 WTA biosynthesis genes rendered normal S. aureus susceptible to Φ187 and enabled Φ187-mediated SaPI transfer from ST395 to regular S. aureus. We provide evidence that exchange of WTA genes and their combination in variable, mosaic-like gene clusters have shaped the evolution of staphylococci and their capacities to undergo horizontal gene transfer events. IMPORTANCE The structural highly diverse wall teichoic acids (WTA) are cell wall-anchored glycopolymers produced by most Gram-positive bacteria. While most of the dominant Staphylococcus aureus lineages produce poly-ribitol-phosphate WTA, the recently described ST395 lineage produces a distinct poly-glycerol-phosphate WTA type resembling the WTA backbone of coagulase-negative staphylococci (CoNS). Here, we analyzed the ST395 WTA biosynthesis pathway and found new types of WTA biosynthesis genes along with an evolutionary link between ST395 and CoNS, from which the ST395 WTA genes probably originate. The elucidation of ST395 WTA biosynthesis will help to understand how Gram-positive bacteria produce highly variable WTA types and elucidate functional consequences of WTA variation.

scholarly journals The Posttranslocational Chaperone Lipoprotein PrsA Is Involved in both Glycopeptide and Oxacillin Resistance in Staphylococcus aureus

2012 ◽  
Vol 56 (7) ◽  
pp. 3629-3640 ◽  
Author(s):  
Ambre Jousselin ◽  
Adriana Renzoni ◽  
Diego O. Andrey ◽  
Antoinette Monod ◽  
Daniel P. Lew ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Wall Stress ◽  
Growth Conditions ◽  
Transcriptional Analysis ◽  
Pharmacological Intervention ◽  
Content Type ◽  
Cell Wall Stress ◽  
Oxacillin Resistance ◽  
Mrsa Strains

ABSTRACTUnderstanding in detail the factors which permitStaphylococcus aureusto counteract cell wall-active antibiotics is a prerequisite to elaborating effective strategies to prolong the usefulness of these drugs and define new targets for pharmacological intervention. Methicillin-resistantS. aureus(MRSA) strains are major pathogens of hospital-acquired and community-acquired infections and are most often treated with glycopeptides (vancomycin and teicoplanin) because of their resistance to most penicillins and a limited arsenal of clinically proven alternatives. In this study, we examined PrsA, a lipid-anchored protein of the parvulin PPIase family (peptidyl-prolylcis/transisomerase) found ubiquitously in all Gram-positive species, in which it assists posttranslocational folding at the outer surface of the cytoplasmic membrane. We show by both genetic and biochemical assays thatprsAis directly regulated by the VraRS two-component sentinel system of cell wall stress. Disruption ofprsAis tolerated byS. aureus, and its loss results in no detectable overt macroscopic changes in cell wall architecture or growth rate under nonstressed growth conditions. Disruption ofprsAleads, however, to notable alterations in the sensitivity to glycopeptides and dramatically decreases the resistance of COL (MRSA) to oxacillin. Quantitative transcriptional analysis reveals thatprsAandvraRare coordinately upregulated in a panel of stable laboratory and clinical glycopeptide-intermediateS. aureus(GISA) strains compared to their susceptible parents. Collectively, our results point to a role forprsAas a facultative facilitator of protein secretion or extracellular folding and provide a framework for understanding whyprsAis a key element of the VraRS-mediated cell wall stress response.

scholarly journals Staphylococcus aureus Mutants Lacking the LytR-CpsA-Psr Family of Enzymes Release Cell Wall Teichoic Acids into the Extracellular Medium

2013 ◽  
Vol 195 (20) ◽  
pp. 4650-4659 ◽  
Author(s):  
Y. G. Y. Chan ◽  
M. B. Frankel ◽  
V. Dengler ◽  
O. Schneewind ◽  
D. Missiakas
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Extracellular Medium ◽  
Teichoic Acids ◽  
Wall Teichoic Acids

scholarly journals A PBP 2 Mutant Devoid of the Transpeptidase Domain Abolishes Spermine–β-Lactam Synergy in Staphylococcus aureus Mu50

2011 ◽  
Vol 56 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Xiangyu Yao ◽  
Chung-Dar Lu
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Wall Stress ◽  
Enzyme Hydrolysis ◽  
Dependent Manner ◽  
Content Type ◽  
C Terminus ◽  
Alkaline Conditions ◽  
Exogenous Spermine ◽  
Ph Range

ABSTRACTExogenous spermine was reported to enhance the killing of methicillin-resistantStaphylococcus aureus(MRSA) by β-lactams through a strong synergistic effect of unknown nature. Spermine alone also exerts an antimicrobial activity againstS. aureusin a pH-dependent manner. MIC measurements revealed stronger effects of spermine under alkaline conditions, suggesting the nucleophilic property of spermine instead of its positive charge as the cause of adverse effects. A spontaneous suppressor mutant (MuM) of MRSA Mu50 was selected for spermine resistance and conferred complete abolishment of spermine–β-lactam synergy. In comparison to that in Mu50, the spermine MIC in MuM remained constant (64 mM) at pH 6 to 8; however, MuM, a heat-sensitive mutant, also grew in a very narrow pH range. Furthermore, MuM acquired a unique phenotype of vancomycin-spermine synergy. Genome resequencing revealed a 7-bp deletion inpbpB, which results in a truncated penicillin-binding protein 2 (PBP 2) without the transpeptidase domain at the C terminus while the N-terminal transglycosidase domain remains intact. The results of fluorescent Bocillin labeling experiments confirmed the presence of this defective PBP 2 in MuM. All the aforementioned phenotypes of MuM were reverted to those of Mu50 after complementation by the wild-typepbpBcarried on a recombinant plasmid. The anticipated changes in cell wall metabolism and composition in MuM were evidenced by observations that the cell wall of MuM was more susceptible to enzyme hydrolysis and that MuM exhibited a lower level of autolytic activities. Pleiotropic alterations in gene expression were revealed by microarray analysis, suggesting a remarkable flexibility of MuM to circumvent cell wall damage by triggering adaptations that are complex but completely different from that of the cell wall stress stimulon. In summary, these results reveal phenotypic changes and transcriptome adaptations in a uniquepbpBmutant and provide evidence to support the idea that exogenous spermine may perturb normal cell wall formation through its interactions with PBP 2.

Analysis of Cell Wall Teichoic Acids in Staphylococcus aureus

2016 ◽  
pp. 201-213 ◽  
Author(s):  
Gonçalo Covas ◽  
Filipa Vaz ◽  
Gabriela Henriques ◽  
Mariana G. Pinho ◽  
Sérgio R. Filipe
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Teichoic Acids ◽  
Wall Teichoic Acids

scholarly journals Effects of Low-Dose Amoxicillin on Staphylococcus aureus USA300 Biofilms

2016 ◽  
Vol 60 (5) ◽  
pp. 2639-2651 ◽  
Author(s):  
Kevin D. Mlynek ◽  
Mary T. Callahan ◽  
Anton V. Shimkevitch ◽  
Jackson T. Farmer ◽  
Jennifer L. Endres ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Biofilm Formation ◽  
Low Dose ◽  
Wall Stress ◽  
Extracellular Dna ◽  
Novel Genes ◽  
Content Type ◽  
Cell Wall Stress ◽  
Mrsa Strains

ABSTRACTPrevious studies showed that sub-MIC levels of β-lactam antibiotics stimulate biofilm formation in most methicillin-resistantStaphylococcus aureus(MRSA) strains. Here, we investigated this process by measuring the effects of sub-MIC amoxicillin on biofilm formation by the epidemic community-associated MRSA strain USA300. We found that sub-MIC amoxicillin increased the ability of USA300 cells to attach to surfaces and form biofilms under both static and flow conditions. We also found that USA300 biofilms cultured in sub-MIC amoxicillin were thicker, contained more pillar and channel structures, and were less porous than biofilms cultured without antibiotic. Biofilm formation in sub-MIC amoxicillin correlated with the production of extracellular DNA (eDNA). However, eDNA released by amoxicillin-induced cell lysis alone was evidently not sufficient to stimulate biofilm. Sub-MIC levels of two other cell wall-active agents with different mechanisms of action—d-cycloserine and fosfomycin—also stimulated eDNA-dependent biofilm, suggesting that biofilm formation may be a mechanistic adaptation to cell wall stress. Screening a USA300 mariner transposon library for mutants deficient in biofilm formation in sub-MIC amoxicillin identified numerous known mediators ofS. aureusβ-lactam resistance and biofilm formation, as well as novel genes not previously associated with these phenotypes. Our results link cell wall stress and biofilm formation in MRSA and suggest that eDNA-dependent biofilm formation by strain USA300 in low-dose amoxicillin is an inducible phenotype that can be used to identify novel genes impacting MRSA β-lactam resistance and biofilm formation.

scholarly journals Wall teichoic acids prevent antibody binding to epitopes within the cell wall of Staphylococcus aureus

2015 ◽  
Vol 11 (1) ◽  
pp. 25-30 ◽  
Author(s):  
Samir Gautam ◽  
Taehan Kim ◽  
Evan Lester ◽  
Deeksha Deep ◽  
David A. Spiegel
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Antibody Binding ◽  
Teichoic Acids ◽  
Wall Teichoic Acids

scholarly journals Mutations inmmpLand in the Cell Wall Stress Stimulon Contribute to Resistance to Oxadiazole Antibiotics in Methicillin-Resistant Staphylococcus aureus

2014 ◽  
Vol 58 (10) ◽  
pp. 5841-5847 ◽  
Author(s):  
Qiaobin Xiao ◽  
Sergei Vakulenko ◽  
Mayland Chang ◽  
Shahriar Mobashery
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Wall Stress ◽  
Methicillin Resistant ◽  
Content Type ◽  
Cell Wall Stress ◽  
A Cell ◽  
Putative Member

ABSTRACTStaphylococcus aureusis a leading cause of hospital- and community-acquired infections, which exhibit broad resistance to various antibiotics. We recently disclosed the discovery of the oxadiazole class of antibiotics, which hasin vitroandin vivoactivities against methicillin-resistantS. aureus(MRSA). We report herein that MmpL, a putative member of the resistance, nodulation, and cell division (RND) family of proteins, contributes to oxadiazole resistance in theS. aureusstrain COL. Through serial passages, we generated twoS. aureusCOL variants that showed diminished susceptibilities to an oxadiazole antibiotic. The MICs for the oxadiazole against one strain (designatedS. aureusCOLI) increased reproducibly 2-fold (to 4 μg/ml), while against the other strain (S. aureusCOLR), they increased >4-fold (to >8 μg/ml, the limit of solubility). The COLRstrain was derived from the COLIstrain. Whole-genome sequencing revealed 31 mutations inS. aureusCOLR, of which 29 were shared with COLI. Consistent with our previous finding that oxadiazole antibiotics inhibit cell wall biosynthesis, we found 13 mutations that occurred either in structural genes or in promoters of the genes of the cell wall stress stimulon. Two unique mutations inS. aureusCOLRwere substitutions in two genes that encode the putative thioredoxin (SACOL1794) and MmpL (SACOL2566). A role formmpLin resistance to oxadiazoles was discerned from gene deletion and complementation experiments. To our knowledge, this is the first report that a cell wall-acting antibiotic selects for mutations in the cell wall stress stimulon and the first to implicate MmpL in resistance to antibiotics inS. aureus.

scholarly journals Epigallocatechin Gallate Induces Upregulation of the Two-Component VraSR System by Evoking a Cell Wall Stress Response in Staphylococcus aureus

2012 ◽  
Vol 78 (22) ◽  
pp. 7954-7959 ◽  
Author(s):  
Oren Levinger ◽  
Tamar Bikels-Goshen ◽  
Elad Landau ◽  
Merav Fichman ◽  
Roni Shapira
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Epigallocatechin Gallate ◽  
Wall Stress ◽  
Null Mutant ◽  
Wild Type ◽  
Content Type ◽  
Cell Wall Stress ◽  
Two Component ◽  
A Cell

ABSTRACTWe previously found that a short exposure ofStaphylococcus aureusto subinhibitory (SI) doses of epigallocatechin gallate (EGCG) results in increased cell wall thickness, adaptation, and enhanced tolerance to cell-wall-targeted antibiotics. In this study, the response to EGCG ofsigBandvraSRtranscription factor mutants was characterized. We show that in contrast to the results observed for wild-type (WT) strains, anS. aureus315vraSRnull mutant exposed to SI doses of EGCG did not exhibit increased tolerance to EGCG and oxacillin. A diminished increase in tolerance to ampicillin (from 16-fold to 4-fold) and no change in the magnitude of resistance to vancomycin were observed. Preexposure to EGCG enhanced the tolerance of wild-type andsigBnull mutant cells to lysostaphin, but this enhancement was much weaker in thevraSRnull mutant. Marked upregulation (about 60-fold) ofvraRand upregulation of the peptidoglycan biosynthesis-associated genesmurA,murF, andpbp2(2-, 5-, and 6-fold, respectively) in response to SI doses of EGCG were determined by quantitative reverse transcription-PCR (qRT-PCR). EGCG also induced the promoter ofsas016(encoding a cell wall stress protein of unknown function which is not induced invraSRnull mutants) in a concentration-dependent manner, showing kinetics comparable to those of cell-wall-targeting antibiotics. Taken together, our results suggest that the two-component VraSR system is involved in modulating the cell response to SI doses of EGCG.

scholarly journals Antimicrobial Activity of the Quinoline Derivative HT61 against Staphylococcus aureus Biofilms

2020 ◽  
Vol 64 (5) ◽  
Author(s):  
C. J. Frapwell ◽  
P. J. Skipp ◽  
R. P. Howlin ◽  
E. M. Angus ◽  
Y. Hu ◽  
...  
Keyword(s):  
Health Care ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Cell Wall ◽  
Wall Stress ◽  
Quinoline Derivative ◽  
Significant Problem ◽  
Content Type ◽  
Health Care Settings ◽  
Cell Wall Stress

ABSTRACT Staphylococcus aureus biofilms are a significant problem in health care settings, partly due to the presence of a nondividing, antibiotic-tolerant subpopulation. Here we evaluated treatment of S. aureus UAMS-1 biofilms with HT61, a quinoline derivative shown to be effective against nondividing Staphylococcus spp. HT61 was effective at reducing biofilm viability and was associated with increased expression of cell wall stress and division proteins, confirming its potential as a treatment for S. aureus biofilm infections.

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