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Small RNA mediated gradual control of lipopolysaccharide biosynthesis affects antibiotic resistance in Helicobacter pylori.

ABSTRACT: The small, regulatory RNA RepG (Regulator of polymeric G-repeats) regulates the expression of the chemotaxis receptor TlpB in Helicobacter pylori by targeting a variable G-repeat in the tlpB mRNA leader. Here, we show that RepG additionally controls lipopolysaccharide (LPS) phase variation by also modulating the expression of a gene (hp0102) that is co-transcribed with tlpB. The hp0102 gene encodes a glycosyltransferase required for LPS O-chain biosynthesis and in vivo colonization of the mouse stomach. The G-repeat length defines a gradual (rather than ON/OFF) control of LPS biosynthesis by RepG, and leads to gradual resistance to a membrane-targeting antibiotic. Thus, RepG-mediated modulation of LPS structure might impact host immune recognition and antibiotic sensitivity, thereby helping H. pylori to adapt and persist in the host.

SUBMITTER: Pernitzsch SR

PROVIDER: S-EPMC8295292 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Small RNA mediated gradual control of lipopolysaccharide biosynthesis affects antibiotic resistance in Helicobacter pylori.

Pernitzsch Sandy R SR Alzheimer Mona M Bremer Belinda U BU Robbe-Saule Marie M De Reuse Hilde H Sharma Cynthia M CM

Nature communications 20210721 1

The small, regulatory RNA RepG (Regulator of polymeric G-repeats) regulates the expression of the chemotaxis receptor TlpB in Helicobacter pylori by targeting a variable G-repeat in the tlpB mRNA leader. Here, we show that RepG additionally controls lipopolysaccharide (LPS) phase variation by also modulating the expression of a gene (hp0102) that is co-transcribed with tlpB. The hp0102 gene encodes a glycosyltransferase required for LPS O-chain biosynthesis and in vivo colonization of the mouse ...[more]

PMID: 34290242

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