Diversity of o-antigen repeat unit structures can account for the substantial sequence variation of wzx translocases.

ABSTRACT: The most common system for synthesis of cell surface polysaccharides is the Wzx/Wzy-dependent pathway, which involves synthesis, on the cytoplasmic face of the cell membrane, of repeat units, which are then translocated to the periplasmic face by a Wzx translocase and then polymerized by Wzy to generate the polysaccharide. One such polysaccharide is O antigen, which is incorporated into lipopolysaccharide (LPS). The O antigen is extremely variable, with over 186 forms in Escherichia coli. Wzx proteins are also very diverse, but they have been thought to be specific only for the first sugar of the repeat units. However, recent studies demonstrated examples in which Wzx translocases have considerable preference for their native repeat unit, showing that specificity can extend well beyond the

SUBMITTER: Hong Y 

PROVIDER: S-EPMC3993327 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature