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Synthase-dependent exopolysaccharide secretion in Gram-negative bacteria.

ABSTRACT: The biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. Recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in Gram-negative bacteria. These components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (TPR)-containing scaffold protein, and an outer-membrane ?-barrel porin. There is also increasing evidence that many synthase-dependent systems are post-translationally regulated by the bacterial second messenger bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP). Here, we compare these core proteins in the context of the alginate, cellulose, and poly-?-D-N-acetylglucosamine (PNAG) secretion systems.

SUBMITTER: Whitney JC

PROVIDER: S-EPMC4113494 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Synthase-dependent exopolysaccharide secretion in Gram-negative bacteria.

Whitney J C JC Howell P L PL

Trends in microbiology 20121029 2

The biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. Recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in Gram-negative bacteria. These components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (TPR)-containing scaffold protein, and an ...[more]

PMID: 23117123

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