LytR-CpsA-Psr proteins in Staphylococcus aureus display partial functional redundancy and the deletion of all three severely impairs septum placement and cell separation

Over, Benjamin; Heusser, Ronald; McCallum, Nadine; Schulthess, Bettina; Kupferschmied, Peter; Gaiani, Jessica M.; Sifri, Costi D.; Berger‐Bächi, Brigitte; Meier, Patricia Stutzmann

doi:10.1111/j.1574-6968.2011.02303.x

Cited by 47 publications

(88 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the basis of these observations, Kawai et al proposed that LCP enzymes recognize WTA or capsular polysaccharide synthesis intermediates as the substrates for the formation of phosphodiester linkages formed between the C6-hydroxyl of MurNAc in peptidoglycan and GlcNAc-ManNAc murein linkage units (30). In agreement with this model, mutants (with the ⌬lcp mutation) lacking all of the three LCP homologues of S. aureus-lcpA (mrsR), lcpB (sa0908), and lcpC (sa2103)-do not harbor phosphate residues in the cell wall envelope (32) and cannot properly place cell division septa (33). Previous work left unresolved whether S. aureus ⌬lcp mutants are defective in the synthesis and/or the cell wall anchoring of WTA and whether their associated cell division defect is due to the sequestration of lipid II within the WTA pathway (32,33).…”

supporting

confidence: 50%

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

et al. 2013

View full text Add to dashboard Cite

cThe LytR-CpsA-Psr (LCP) proteins are thought to transfer bactoprenol-linked biosynthetic intermediates of wall teichoic acid (WTA) to the peptidoglycan of Gram-positive bacteria. In Bacillus subtilis, mutants lacking all three LCP enzymes do not deposit WTA in the envelope, while Staphylococcus aureus ⌬lcp mutants display impaired growth and reduced levels of envelope phosphate. We show here that the S. aureus ⌬lcp mutant synthesized WTA yet released ribitol phosphate polymers into the extracellular medium. Further, ⌬lcp mutant staphylococci no longer restricted the deposition of LysM-type murein hydrolases to cell division sites, which was associated with defects in cell shape and increased autolysis. Mutations in S. aureus WTA synthesis genes (tagB, tarF, or tarJ2) inhibit growth, which is attributed to the depletion of bactoprenol, an essential component of peptidoglycan synthesis (lipid II). The growth defect of S. aureus tagB and tarFJ mutants was alleviated by inhibition of WTA synthesis with tunicamycin, whereas the growth defect of the ⌬lcp mutant was not relieved by tunicamycin treatment or by mutation of tagO, whose product catalyzes the first committed step of WTA synthesis. Further, sortase A-mediated anchoring of proteins to peptidoglycan, which also involves bactoprenol and lipid II, was not impaired in the ⌬lcp mutant. We propose a model whereby the S. aureus ⌬lcp mutant, defective in tethering WTA to the cell wall, cleaves WTA synthesis intermediates, releasing ribitol phosphate into the medium and recycling bactoprenol for peptidoglycan synthesis.

show abstract

supporting

confidence: 50%

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

et al. 2013

View full text Add to dashboard Cite

show abstract

“…c-proteobacteria, the yjeE locus is closely linked to genes encoding proteins with potential functions in DNA repair and peptidoglycan remodelling, which is consistent with a role for YjeE in stress tolerance and cell envelope biogenesis (Handford et al, 2009;Teplyakov et al, 2002 Kawai et al, 2011;Over et al, 2011;Wen et al, 2006). This highly conserved genetic linkage, along with the characteristic phenotypes of the BrpB-deficient mutants, all support a role for BrpB and its streptococcal homologues in cell wall biogenesis/homeostasis.…”

Section: Ua159mentioning

confidence: 72%

“…mutans species are the only streptococci lacking the acyltransferase locus, a likely result of genetic deletions during the evolutionary processes and an attributing factor to the presence of a large intergenic region between brpA and brpB (Bitoun et al, 2012a). Unlike streptococci, however, no such linkage could be identified between the loci for YjeE (or YdiB for B. subtilis) homologues and the genes for any LCP proteins in Staphylococcus aureus, B. subtilis and other Gram-positive bacteria (Eberhardt et al, 2012;Johnsborg & Håvarstein, 2009;Kawai et al, 2011;Over et al, 2011).…”

Section: Resultsmentioning

confidence: 99%

Deficiency of BrpB causes major defects in cell division, stress responses and biofilm formation by Streptococcus mutans

et al. 2014

View full text Add to dashboard Cite

Streptococcus mutans, the primary aetiological agent of dental caries, possesses an YjeE-like protein that is encoded by locus SMU.409, herein designated brpB. In this study, a BrpBdeficient mutant, JB409, and a double mutant deficient of BrpB and BrpA (a paralogue of the LytR-CpsA-Psr family of cell wall-associated proteins), JB819, were constructed and characterized using function assays and microscopy analysis. Both JB409 and JB819 displayed extended lag phases and drastically slowed growth rates during growth in brain heart infusion medium as compared to the wild-type, UA159. Relative to UA159, JB409 and JB819 were more than 60-and 10-fold more susceptible to acid killing at pH 2.8, and more than 1 and 2 logs more susceptible to hydrogen peroxide, respectively. Complementation of the deficient mutants with a wild-type copy of the respective gene(s) partly restored the acid and oxidative stress responses to a level similar to the wild-type. As compared to UA159, biofilm formation by JB409 and JB819 was drastically reduced (P,0.001), especially during growth in medium containing sucrose. Under a scanning electron microscope, JB409 had significantly more giant cells with an elongated, rod-like morphology, and JB819 formed marble-like super cells with apparent defects in cell division. As revealed by transmission electron microscopy analysis, BrpB deficiency in both JB409 and JB819 resulted in the development of low electron density patches and formation of a loose nucleoid structure. Taken together, these results suggest that BrpB likely functions together with BrpA in regulating cell envelope biogenesis/homeostasis in Strep. mutans. Further studies are under way to elucidate the mechanism that underlies the BrpA-and BrpB-mediated regulation.

show abstract

“…Mutations in the synthesis pathway for wall teichoic acid (WTA), polyribitol phosphate modified with D-alanyl and N-acetylglucosaminyl and tethered via murein linkage units to peptidoglycan (58), also cause defects in the premature assembly of septal peptidoglycan (41,59,60). We asked whether S. aureus mutants lacking glucosaminidase genes are defective for WTA assembly.…”

Section: N-acetylglucosaminidases Of Staphylococcus Aureus Newmanmentioning

confidence: 99%

SagB Glucosaminidase Is a Determinant of Staphylococcus aureus Glycan Chain Length, Antibiotic Susceptibility, and Protein Secretion

et al. 2016

View full text Add to dashboard Cite

The envelope of Staphylococcus aureus is comprised of peptidoglycan and its attached secondary polymers, teichoic acid, capsular polysaccharide, and protein. Peptidoglycan synthesis involves polymerization of lipid II precursors into glycan strands that are cross-linked at wall peptides. It is not clear whether peptidoglycan structure is principally determined during polymerization or whether processive enzymes affect cell wall structure and function, for example, by generating conduits for protein secretion. We show here that S. aureus lacking SagB, a membrane-associated N-acetylglucosaminidase, displays growth and cell-morphological defects caused by the exaggerated length of peptidoglycan strands. SagB cleaves polymerized glycan strands to their physiological length and modulates antibiotic resistance in methicillin-resistant S. aureus (MRSA). Deletion of sagB perturbs protein trafficking into and across the envelope, conferring defects in cell wall anchoring and secretion, as well as aberrant excretion of cytoplasmic proteins. IMPORTANCEStaphylococcus aureus is thought to secrete proteins across the plasma membrane via the Sec pathway; however, protein transport across the cell wall envelope has heretofore not been studied. We report that S. aureus sagB mutants generate elongated peptidoglycan strands and display defects in protein secretion as well as aberrant excretion of cytoplasmic proteins. These results suggest that the thick peptidoglycan layer of staphylococci presents a barrier for protein secretion and that SagB appears to extend the Sec pathway across the cell wall envelope. Staphylococcus aureus, a Gram-positive bacterial pathogen, replicates via septal assembly of membranes and peptidoglycan into the cross wall compartment (1, 2). The peptidoglycan of the cross wall is split by murein hydrolases, separating daughter cells that assume a spherical shape (3). Earlier work identified three murein hydrolases with cross-wall-splitting activities: Atl (autolysin), Sle1, and LytN (3-5). Atl and Sle1 are secreted into the extracellular milieu and subsequently cleave septal peptidoglycan at the cross wall but not elsewhere as access is restricted by teichoic acid modification of peptidoglycan (6-8). LytN, on the other hand, is secreted into the cross wall compartment (5). S. aureus Atl is synthesized as a preproenzyme with an N-terminal signal peptide and prodomain (9, 10). Secreted pro-Atl is processed to generate Atl N-acetylmuramoyl-L-Ala-amidase (Atl AM ) and Atl Nacetylglucosaminidase (Atl GL ), and each binds via GW domains to lipoteichoic acids (10-12). Earlier work demonstrated that Atl functions as an endo-␤-N-acetylglucosaminidase (12, 13). Although initially designated autolysin (Atl), the S. aureus atl mutant does not display an autolysis phenotype yet forms large clusters of incompletely separated bacteria and is defective for penicillin-induced killing (14). The LysM domains of Sle1 promote its binding to cross wall peptidoglycan, and sle1 mutants also form clusters of incompletely s...

show abstract

LytR-CpsA-Psr proteins in Staphylococcus aureus display partial functional redundancy and the deletion of all three severely impairs septum placement and cell separation

Cited by 47 publications

References 28 publications

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

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

Deficiency of BrpB causes major defects in cell division, stress responses and biofilm formation by Streptococcus mutans

SagB Glucosaminidase Is a Determinant of Staphylococcus aureus Glycan Chain Length, Antibiotic Susceptibility, and Protein Secretion

Contact Info

Product

Resources

About