Structure-function studies of the C3/C5 epimerases and C4 reductases of the Campylobacter jejuni capsular heptose modification pathways.

ABSTRACT: Many bacteria produce polysaccharide-based capsules that protect them from environmental insults and play a role in virulence, host invasion, and other functions. Understanding how the polysaccharide components are synthesized could provide new means to combat bacterial infections. We have previously characterized two pairs of homologous enzymes involved in the biosynthesis of capsular sugar precursors GDP-6-deoxy-D-altro-heptose and GDP-6-OMe-L-gluco-heptose in Campylobacter jejuni. However, the substrate specificity and mechanism of action of these enzymes-C3 and/or C5 epimerases DdahB and MlghB and C4 reductases DdahC and MlghC-are unknown. Here, we demonstrate that these enzymes are highly specific for heptose substrates, using mannose substrates inefficiently with the exception of Mlg

SUBMITTER: Barnawi H 

PROVIDER: S-EPMC7949155 | biostudies-literature | 2021 Jan-Jun

REPOSITORIES: biostudies-literature