Download MendeleyStructural analysis of the sialyltransferase CstII from Campylobacter jejuni in complex with a substrate analog.
Chiu, C.P., Watts, A.G., Lairson, L.L., Gilbert, M., Lim, D., Wakarchuk, W.W., Withers, S.G., Strynadka, N.C.(2004) Nat Struct Mol Biol 11: 163-170
- PubMed: 14730352
- DOI: https://doi.org/10.1038/nsmb720
- Primary Citation of Related Structures:
1RO7, 1RO8 - PubMed Abstract:
Sialic acid terminates oligosaccharide chains on mammalian and microbial cell surfaces, playing critical roles in recognition and adherence. The enzymes that transfer the sialic acid moiety from cytidine-5'-monophospho-N-acetyl-neuraminic acid (CMP-NeuAc) to the terminal positions of these key glycoconjugates are known as sialyltransferases. Despite their important biological roles, little is understood about the mechanism or molecular structure of these membrane-associated enzymes. We report the first structure of a sialyltransferase, that of CstII from Campylobacter jejuni, a highly prevalent foodborne pathogen. Our structural, mutagenesis and kinetic data provide support for a novel mode of substrate binding and glycosyl transfer mechanism, including essential roles of a histidine (general base) and two tyrosine residues (coordination of the phosphate leaving group). This work provides a framework for understanding the activity of several sialyltransferases, from bacterial to human, and for the structure-based design of specific inhibitors.
Organizational Affiliation:
Department of Biochemistry and Molecular Biology, University of British Columbia, 2146 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada.
