In vitro bacterial polysaccharide biosynthesis: defining the functions of Wzy and Wzz.

Polysaccharides constitute a major component of bacterial cell surfaces and play critical roles in bacteria-host interactions. The biosynthesis of such molecules, however, has mainly been characterized through in vivo genetic studies, thus precluding discernment of the details of this pathway. Accordingly, we present a chemical approach that enabled reconstitution of the E.

In vitro reconstitution of Escherichia coli O86 O antigen repeating unit.

Polysaccharides constitute a major component of the bacterial cell surface. They play critical roles in the interactions between bacteria and the host environments, and consequently contribute to the virulence of pathogens. The lipopolysaccharide (LPS) found on the surface of gram-negative bacteria consists of three parts: lipid A, a core oligosaccharide, and the O antigen.

Structural basis and catalytic mechanism for the dual functional endo-beta-N-acetylglucosaminidase A.

Endo-beta-N-acetylglucosaminidases (ENGases) are dual specificity enzymes with an ability to catalyze hydrolysis and transglycosylation reactions. Recently, these enzymes have become the focus of intense research because of their potential for synthesis of glycopeptides. We have determined the 3D structures of an ENGase from Arthrobacter protophormiae (Endo-A) in 3 forms, one in native form, one in complex with Man(3)GlcNAc-thiazoline and another in complex with GlcNAc-Asn.