scholarly journals YycH and YycI Regulate Expression of Staphylococcus aureus Autolysins by Activation of WalRK Phosphorylation

2020 ◽  
Vol 8 (6) ◽  
pp. 870
Author(s):  
Mike Gajdiss ◽  
Ian R. Monk ◽  
Ute Bertsche ◽  
Janina Kienemund ◽  
Tanja Funk ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Teichoic Acid ◽  
Regulatory System ◽  
Regulatory Function ◽  
Wall Teichoic Acid ◽  
Dependent Cell ◽  
Severe Infections

Staphylococcus aureus is a facultative pathogen that can encode numerous antibiotic resistance and immune evasion genes and can cause severe infections. Reduced susceptibility to last resort antibiotics such as vancomycin and daptomycin is often associated with mutations in walRK, an essential two-component regulatory system (TCS). This study focuses on the WalK accessory membrane proteins YycH and YycI and their influence on WalRK phosphorylation. Depletion of YycH and YycI by antisense RNA caused an impaired autolysis, indicating a positive regulatory function on WalK as has been previously described. Phosphorylation assays with full-length recombinant proteins in phospholipid liposomes showed that YycH and YycI stimulate WalK activity and that both regulatory proteins are needed for full activation of the WalK kinase. This was validated in vivo through examining the phosphorylation status of WalR using Phos-tag SDS-PAGE with a yycHI deletion mutant exhibiting reduced levels of phosphorylated WalR. In the yycHI knockdown strain, muropeptide composition of the cell wall was not affected, however, the wall teichoic acid content was increased. In conclusion, a direct modulation of WalRK phosphorylation activity by the accessory proteins YycH and YycI is reported both in vitro and in vivo. Taken together, our results show that YycH and YycI are important in the direct regulation of WalRK-dependent cell wall metabolism.

scholarly journals The impact of Staphylococcus aureus cell wall glycosylation on langerin recognition and Langerhans cell activation

2020 ◽  
Author(s):  
A Hendriks ◽  
R van Dalen ◽  
S Ali ◽  
D Gerlach ◽  
GA van der Marel ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Cell Activation ◽  
Teichoic Acid ◽  
Binding Studies ◽  
Wall Teichoic Acid ◽  
Linkage Position ◽  
Antigen Presenting ◽  
The Impact

AbstractStaphylococcus aureus is the leading cause of skin and soft tissue infections. It remains incompletely understood how skin-resident immune cells respond to S. aureus invasion and contribute to an effective immune response. Langerhans cells (LCs), the only professional antigen-presenting cell type in the epidermis, sense S. aureus through their pattern-recognition receptor langerin, triggering a pro-inflammatory response. Langerin specifically recognizes the β-1,4-linked N-acetylglucosamine (β-GlcNAc) modification, which requires the glycosyltransferase TarS, on the cell wall glycopolymer Wall Teichoic Acid (WTA). Recently, an alternative WTA glycosyltransferase, TarP, was identified in methicillin-resistant S. aureus strains belonging to clonal complexes (CC) 5 and CC398. TarP also modifies WTA with β-GlcNAc but at the C-3 position of the WTA ribitol phosphate (RboP) subunit. Here, we aimed to unravel the impact of β-GlcNAc linkage position for langerin binding and LC activation. In addition, we performed structure-binding studies using a small panel of unique chemically-synthesized WTA molecules to assess langerin-WTA binding requirements. Using FITC-labeled recombinant human langerin and genetically-modified S. aureus strains, we observed that langerin similarly recognized bacteria that produce either TarS- or TarP-modified WTA. Furthermore, using chemically-synthesized WTA, representative of the different S. aureus WTA glycosylation patterns, established that β-GlcNAc is sufficient to confer langerin binding. Functionally, tarP-expressing S. aureus induce increased cytokine production and maturation of in vitro-generated LCs compared to tarSexpressing S. aureus. Overall, our data suggest that LCs are able to sense all β-GlcNAc-WTA producing S. aureus strains, likely performing an important role as first responders upon S. aureus skin invasion.

scholarly journals Human monoclonal antibodies against Staphylococcus aureus surface antigens recognize in vitro biofilm and in vivo implant infections

2021 ◽  
Author(s):  
Lisanne de Vor ◽  
Bruce van Dijk ◽  
Kok P.M. van Kessel ◽  
Jeffrey S. Kavanaugh ◽  
Carla J.C. de Haas ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Monoclonal Antibodies ◽  
Biofilm Formation ◽  
Teichoic Acid ◽  
Human Monoclonal Antibodies ◽  
Human Mabs ◽  
Wall Teichoic Acid ◽  
Alternative Approach

AbstractImplant-associated Staphylococcus aureus infections are difficult to treat because of biofilm formation. Bacteria in a biofilm are often insensitive to antibiotics and host immunity. Monoclonal antibodies (mAbs) could provide an alternative approach to improve the diagnosis and/or treatment of biofilm-related infections. Here we show that mAbs targeting common surface components of S. aureus can recognize clinically relevant biofilm types. We identify two groups of antibodies: one group that uniquely binds S. aureus in biofilm state and one that recognizes S. aureus in both biofilm and planktonic state. In a mouse model, we show that mAb 4497 (recognizing wall teichoic acid (WTA)) specifically localizes to biofilm-infected implants. In conclusion, we demonstrate the capacity of several human mAbs to detect S. aureus biofilms in vitro and in vivo. This is an important first step to develop mAbs for imaging or treating S. aureus biofilms.

scholarly journals An Antibiotic That Inhibits a Late Step in Wall Teichoic Acid Biosynthesis Induces the Cell Wall Stress Stimulon in Staphylococcus aureus

2012 ◽  
Vol 56 (4) ◽  
pp. 1810-1820 ◽  
Author(s):  
Jennifer Campbell ◽  
Atul K. Singh ◽  
Jonathan G. Swoboda ◽  
Michael S. Gilmore ◽  
Brian J. Wilkinson ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Osmotic Stress ◽  
Late Stage ◽  
Teichoic Acid ◽  
Wall Stress ◽  
Wall Teichoic Acid ◽  
Content Type ◽  
Cell Wall Stress

ABSTRACTWall teichoic acids (WTAs) are phosphate-rich, sugar-based polymers attached to the cell walls of most Gram-positive bacteria. InStaphylococcus aureus, these anionic polymers regulate cell division, protect cells from osmotic stress, mediate host colonization, and mask enzymatically susceptible peptidoglycan bonds. Although WTAs are not required for survivalin vitro, blocking the pathway at a late stage of synthesis is lethal. We recently discovered a novel antibiotic, targocil, that inhibits a late acting step in the WTA pathway. Its target is TarG, the transmembrane component of the ABC transporter (TarGH) that exports WTAs to the cell surface. We examined here the effects of targocil onS. aureususing transmission electron microscopy and gene expression profiling. We report that targocil treatment leads to multicellular clusters containing swollen cells displaying evidence of osmotic stress, strongly induces the cell wall stress stimulon, and reduces the expression of key virulence genes, includingdltABCDand capsule genes. We conclude that WTA inhibitors that act at a late stage of the biosynthetic pathway may be useful as antibiotics, and we present evidence that they could be particularly useful in combination with beta-lactams.

scholarly journals VraT/YvqF Is Required for Methicillin Resistance and Activation of the VraSR Regulon in Staphylococcus aureus

2012 ◽  
Vol 57 (1) ◽  
pp. 83-95 ◽  
Author(s):  
Susan Boyle-Vavra ◽  
Shouhui Yin ◽  
Dae Sun Jo ◽  
Christopher P. Montgomery ◽  
Robert S. Daum
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Methicillin Resistance ◽  
Regulatory System ◽  
Microarray Experiments ◽  
Content Type ◽  
Genome Wide ◽  
Mrsa Strains

ABSTRACTStaphylococcus aureusinfections caused by strains that are resistant to all forms of penicillin, so-called methicillin-resistantS. aureus(MRSA) strains, have become common. One strategy to counter MRSA infections is to use compounds that resensitize MRSA to methicillin.S. aureusresponds to diverse classes of cell wall-inhibitory antibiotics, like methicillin, using the two-component regulatory system VraSR (vra) to up- or downregulate a set of genes (the cell wall stimulon) that presumably facilitates resistance to these antibiotics. Accordingly, VraS and VraR mutations decrease resistance to methicillin, vancomycin, and daptomycin cell wall antimicrobials.vraSandvraRare encoded together on a transcript downstream of two other genes, which we callvraUandvraT(previously calledyvqF). By producing nonpolar deletions invraUandvraTin a USA300 MRSA clinical isolate, we demonstrate thatvraTis essential for optimal expression of methicillin resistancein vitro, whereasvraUis not required for this phenotype. The deletion ofvraTalso improved the outcomes of oxacillin therapy in mouse models of lung and skin infection. SincevraTexpressed intransdid not complement avraoperon deletion, we conclude that VraT does not inactivate the antimicrobial. Genome-wide transcriptional microarray experiments reveal that VraT facilitates resistance by playing a necessary regulatory role in the VraSR-mediated cell wall stimulon. Our data prove that VraTSR comprise a novel three-component regulatory system required to facilitate resistance to cell wall agents inS. aureus. We also provide the firstin vivoproof of principle for using VraT as a sole target to resensitize MRSA to β-lactams.

scholarly journals Duplication of Teichoic Acid Biosynthetic Genes in Staphylococcus aureus Leads to Functionally Redundant Poly(Ribitol Phosphate) Polymerases

2008 ◽  
Vol 190 (16) ◽  
pp. 5642-5649 ◽  
Author(s):  
Mark P. Pereira ◽  
Michael A. D'Elia ◽  
Justyna Troczynska ◽  
Eric D. Brown
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Teichoic Acid ◽  
Gene Clusters ◽  
Opportunistic Pathogen ◽  
Null Mutant ◽  
Wall Teichoic Acid ◽  
Rate Limiting Step ◽  
Wall Teichoic Acids

ABSTRACT Wall teichoic acids are anionic phosphate-rich polymers that are part of the complex meshwork of carbohydrates that make up the gram-positive cell wall. These polymers are essential to the proper rod-shaped morphology of Bacillus subtilis and have been shown to be an important virulence determinant in the nosocomial opportunistic pathogen Staphylococcus aureus. Together, sequence-based studies, in vitro experiments with biosynthetic proteins, and analyses of the chemical structure of wall teichoic acid have begun to shed considerable light on our understanding of the biogenesis of this polymer. Nevertheless, some paradoxes remain unresolved. One of these involves a putative duplication of genes linked to CDP-ribitol synthesis (tarI′J′ and tarIJ) as well as poly(ribitol phosphate) polymerization (tarK and tarL) in S. aureus. In the work reported here, we performed careful studies of the dispensability of each gene and discovered a functional redundancy in the duplicated gene clusters. We were able to create mutants in either of the putative ribitol phosphate polymerases (encoded by tarK and tarL) without affecting teichoic acid levels in the S. aureus cell wall. Although genes linked to CDP-ribitol synthesis are also duplicated, a null mutant in only one of these (tarI′J′) could be obtained, while tarIJ remained essential. Suppression analysis of the tarIJ null mutant indicated that the mechanism of dysfunction in tarI′J′ is due to poor translation of the TarJ′ enzyme, which catalyzes the rate-limiting step in CDP-ribitol formation. This work provides new insights into understanding the complex synthetic steps of the ribitol phosphate polymer in S. aureus and has implications on specifically targeting enzymes involved in polymer biosynthesis for antimicrobial design.

scholarly journals Human monoclonal antibodies against Staphylococcus aureus surface antigens recognize in vitro and in vivo biofilm

eLife ◽  
2022 ◽  
Vol 11 ◽  
Author(s):  
Lisanne de Vor ◽  
Bruce van Dijk ◽  
Kok van Kessel ◽  
Jeffrey S Kavanaugh ◽  
Carla de Haas ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Monoclonal Antibodies ◽  
Teichoic Acid ◽  
Human Monoclonal Antibodies ◽  
Human Mabs ◽  
Wall Teichoic Acid ◽  
Prosthetic Joint ◽  
Alternative Approach

Implant-associated Staphylococcus aureus infections are difficult to treat because of biofilm formation. Bacteria in a biofilm are often insensitive to antibiotics and host immunity. Monoclonal antibodies (mAbs) could provide an alternative approach to improve the diagnosis and potential treatment of biofilm-related infections. Here, we show that mAbs targeting common surface components of S. aureus can recognize clinically relevant biofilm types. The mAbs were also shown to bind a collection of clinical isolates derived from different biofilm-associated infections (endocarditis, prosthetic joint, catheter). We identify two groups of antibodies: one group that uniquely binds S. aureus in biofilm state and one that recognizes S. aureus in both biofilm and planktonic state. Furthermore, we show that a mAb recognizing wall teichoic acid (clone 4497) specifically localizes to a subcutaneously implanted pre-colonized catheter in mice. In conclusion, we demonstrate the capacity of several human mAbs to detect S. aureus biofilms in vitro and in vivo.

scholarly journals Glycosylation of Staphylococcus aureus cell wall teichoic acid is influenced by environmental conditions

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Noëlle Mistretta ◽  
Marina Brossaud ◽  
Fabienne Telles ◽  
Violette Sanchez ◽  
Philippe Talaga ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Environmental Conditions ◽  
Teichoic Acid ◽  
Wall Teichoic Acid

THE MODE OF ACTION OF THE ANTIBIOTIC PAROMOMYCIN ON STAPHYLOCOCCUS AUREUS

1966 ◽  
Vol 12 (6) ◽  
pp. 1157-1165 ◽  
Author(s):  
A. von Seefried ◽  
D. C. Jordan
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Binding Sites ◽  
Bactericidal Action ◽  
Plate Method ◽  
Vitro Binding ◽  
Resistant Mutants ◽  
Intracellular Binding

Paromomycin (Humatin, Parke Davis & Co.), a broad-spectrum aminoglycosidic antibiotic, inhibits the incorporation of amino acids into the trypsinsoluble protein fraction of Staphylococcus aureus 257. Protein synthesis is inhibited immediately, but the synthesis of cell-wall mucopeptide and alcohol-soluble proteins and lipids is not affected for approximately 35 min after antibiotic addition to actively growing cells. Paromomycin, at the ribosomal level, prevents the attachment of amino acyl-s-RNA and causes accumulation of m-RNA.Divalent cations (Ca++ and Mg++) antagonize the bactericidal action of paromomycin and interfere with the in vivo binding of the antibiotic on both the cell surface and the intracellular binding sites. In vitro binding to free ribosomes can be prevented and reversed by both monovalent and divalent cations.Using a "cylinder-plate" method, involving the displacement of antibiotic from cellular fractions by 0.2 M MgCl2, the antibiotic can be recovered from the ribosomes, cytoplasm, and the cell wall of paromomycin-sensitive S. aureus cells, but is not found in any of these fractions isolated from paromomycin-resistant cells developed from the sensitive parent strain. The resistant mutants apparently have lost the ability to adsorb and transport the antibiotic into the cell.

Sign in / Sign up

Export Citation Format

Share Document