Download MendeleyThe biosynthetic origin of ribofuranose in bacterial polysaccharides.
Kelly, S.D., Williams, D.M., Nothof, J.T., Kim, T., Lowary, T.L., Kimber, M.S., Whitfield, C.(2022) Nat Chem Biol 18: 530-537
- PubMed: 35393575
- DOI: https://doi.org/10.1038/s41589-022-01006-6
- Primary Citation of Related Structures:
7SHG - PubMed Abstract:
Bacterial surface polysaccharides are assembled by glycosyltransferase enzymes that typically use sugar nucleotide or polyprenyl-monophosphosugar activated donors. Characterized representatives exist for many monosaccharides but neither the donor nor the corresponding glycosyltransferases have been definitively identified for ribofuranose residues found in some polysaccharides. Klebsiella pneumoniae O-antigen polysaccharides provided prototypes to identify dual-domain ribofuranosyltransferase proteins catalyzing a two-step reaction sequence. Phosphoribosyl-5-phospho-D-ribosyl-α-1-diphosphate serves as the donor for a glycan acceptor-specific phosphoribosyl transferase (gPRT), and a more promiscuous phosphoribosyl-phosphatase (PRP) then removes the residual 5'-phosphate. The 2.5-Å resolution crystal structure of a dual-domain ribofuranosyltransferase ortholog from Thermobacillus composti revealed a PRP domain that conserves many features of the phosphatase members of the haloacid dehalogenase family, and a gPRT domain that diverges substantially from all previously characterized phosphoribosyl transferases. The gPRT represents a new glycosyltransferase fold conserved in the most abundant ribofuranosyltransferase family.
Organizational Affiliation:
Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada.
