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O-Acetylation of peptidoglycan is required for proper cell separation and S-layer anchoring in Bacillus anthracis.

ABSTRACT: O-Acetylation of the MurNAc moiety of peptidoglycan is typically associated with bacterial resistance to lysozyme, a muramidase that serves as a central component of innate immunity. Here, we report that the peptidoglycan of Bacillus anthracis, the etiological agent of anthrax, is O-acetylated and that, unusually, this modification is produced by two unrelated families of O-acetyltransferases. Also, in contrast to other bacteria, O-acetylation of B. anthracis peptidoglycan is combined with N-deacetylation to confer resistance of cells to lysozyme. Activity of the Pat O-acetyltransferases is required for the separation of the daughter cells following bacterial division and for anchoring of one of the major S-layer proteins. Our results indicate that peptidoglycan O-acetylation modulates endogenous muramidase activity affecting the cell-surface properties and morphology of this important pathogen.

SUBMITTER: Laaberki MH

PROVIDER: S-EPMC3037640 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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O-Acetylation of peptidoglycan is required for proper cell separation and S-layer anchoring in Bacillus anthracis.

Laaberki Maria-Halima MH Pfeffer John J Clarke Anthony J AJ Dworkin Jonathan J

The Journal of biological chemistry 20101206 7

O-Acetylation of the MurNAc moiety of peptidoglycan is typically associated with bacterial resistance to lysozyme, a muramidase that serves as a central component of innate immunity. Here, we report that the peptidoglycan of Bacillus anthracis, the etiological agent of anthrax, is O-acetylated and that, unusually, this modification is produced by two unrelated families of O-acetyltransferases. Also, in contrast to other bacteria, O-acetylation of B. anthracis peptidoglycan is combined with N-dea ...[more]

PMID: 21135105

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