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A Staphylococcus aureus ypfP mutant with strongly reduced lipoteichoic acid (LTA) content: LTA governs bacterial surface properties and autolysin activity.

ABSTRACT: Many Gram-positive bacteria produce lipoteichoic acid (LTA) polymers whose physiological roles have remained a matter of debate because of the lack of LTA-deficient mutants. The ypfP gene responsible for biosynthesis of a glycolipid found in LTA was deleted in Staphylococcus aureus SA113, causing 87% reduction of the LTA content. Mass spectrometry and nuclear magnetic resonance spectroscopy revealed that the mutant LTA contained a diacylglycerol anchor instead of the glycolipid, whereas the remaining part was similar to the wild-type polymer except that it was shorter. The LTA mutant strain revealed no major changes in patterns of cell wall proteins or autolytic enzymes compared with the parental strain indicating that LTA may be less important in S. aureus protein attachment than previously thought. However, the autolytic activity of the mutant was strongly reduced demonstrating a role of LTA in controlling autolysin activity. Moreover, the hydrophobicity of the LTA mutant was altered and its ability to form biofilms on plastic was completely abrogated indicating a profound impact of LTA on physicochemical properties of bacterial surfaces. We propose to consider LTA and its biosynthetic enzymes as targets for new antibiofilm strategies.

SUBMITTER: Fedtke I

PROVIDER: S-EPMC2169524 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Secreted proteases control autolysin-mediated biofilm growth of Staphylococcus aureus.

Project description:Staphylococcus epidermidis, a commensal of humans, secretes Esp protease to prevent Staphylococcus aureus biofilm formation and colonization. Blocking S. aureus colonization may reduce the incidence of invasive infectious diseases; however, the mechanism whereby Esp disrupts biofilms is unknown. We show here that Esp cleaves autolysin (Atl)-derived murein hydrolases and prevents staphylococcal release of DNA, which serves as extracellular matrix in biofilms. The three-dimensional structure of Esp was revealed by x-ray crystallography and shown to be highly similar to that of S. aureus V8 (SspA). Both atl and sspA are necessary for biofilm formation, and purified SspA cleaves Atl-derived murein hydrolases. Thus, S. aureus biofilms are formed via the controlled secretion and proteolysis of autolysin, and this developmental program appears to be perturbed by the Esp protease of S. epidermidis.

| S-EPMC3795244 | biostudies-literature

Synthesis of glycerol phosphate lipoteichoic acid in Staphylococcus aureus.

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| S-EPMC1895975 | biostudies-literature

Proteolytic cleavage inactivates the Staphylococcus aureus lipoteichoic acid synthase.

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| S-EPMC3187375 | biostudies-literature

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Human whole blood stimulated with Pam2Cys and lipoteichoic acid from Staphylococcus aureus wt and delta-lgt mutant

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2015-04-05 | GSE21188 | GEO

The multifunctional Staphylococcus aureus autolysin aaa mediates adherence to immobilized fibrinogen and fibronectin.

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| S-EPMC1201280 | biostudies-literature

Genes required for glycolipid synthesis and lipoteichoic acid anchoring in Staphylococcus aureus.

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Wall Teichoic Acid Glycosylation Governs Staphylococcus aureus Nasal Colonization.

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Project description:HL-60 is a human promyelocytic leukemia cell line and differentiated HL-60 is an alternative to human primary neutrophils. The transcriptomic profile of undifferentiated HL-60 and dimethyl sulfoxide-differentiated HL-60 were determined at 4 and 24 hours after stimulation with high and low concentrations of Staphylococcus aureus lipoteichoic acids.

2023-12-15 | GSE239859 | GEO

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