1. Bacteriophage predation promotes serovar diversification inListeria monocytogenes
- Author
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Alexandre Leclercq, Vanessa J. Hüls, Marcel R. Eugster, Laurent S. Morax, Martin J. Loessner, Simona G. Huwiler, and Marc Lecuit
- Subjects
Genetics ,0303 health sciences ,Glycosylation ,030306 microbiology ,Rhamnose ,Point mutation ,Biology ,Gene mutation ,biology.organism_classification ,Microbiology ,Complementation ,Bacteriophage ,03 medical and health sciences ,chemistry.chemical_compound ,chemistry ,Genetic variation ,Molecular Biology ,Gene ,030304 developmental biology - Abstract
Summary Listeria monocytogenes is a bacterial pathogen classified into distinct serovars (SVs) based on somatic and flagellar antigens. To correlate phenotype with genetic variation, we analyzed the wall teichoic acid (WTA) glycosylation genes of SV 1/2, 3 and 7 strains, which differ in decoration of the ribitol-phosphate backbone with N-acetylglucosamine (GlcNAc) and/or rhamnose. Inactivation of lmo1080 or the dTDP-l-rhamnose biosynthesis genes rmlACBD (lmo1081–1084) resulted in loss of rhamnose, whereas disruption of lmo1079 led to GlcNAc deficiency. We found that all SV 3 and 7 strains actually originate from a SV 1/2 background, as a result of small mutations in WTA rhamnosylation and/or GlcNAcylation genes. Genetic complementation of different SV 3 and 7 isolates using intact alleles fully restored a characteristic SV 1/2 WTA carbohydrate pattern, including antisera reactions and phage adsorption. Intriguingly, phage-resistant L. monocytogenes EGDe (SV 1/2a) isolates featured the same glycosylation gene mutations and were serotyped as SV 3 or 7 respectively. Again, genetic complementation restored both carbohydrate antigens and phage susceptibility. Taken together, our data demonstrate that L. monocytogenes SV 3 and 7 originate from point mutations in glycosylation genes, and we show that phage predation represents a major driving force for serovar diversification and evolution of L. monocytogenes.
- Published
- 2015
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