Reaction: n lipid-linked O-antigen repeat units = a lipid-linked O antigen + (n–1) polyisoprenyl diphosphate
Other name(s): wzy (gene name); rfc (gene name); Wzy O-antigen polymerase; Wzy polymerase
Systematic name: lipid-linked O-antigen repeat unit:O-antigen O-antigen repeat-unit transferase
Comments: The Wzy-type polymerase polymerizes O antigen repeat unit oligosaccharides that are anchored to the periplasmic face of the inner membrane, forming an O antigen polysaccharide that is still anchored to the membrane. A Wzz chain length regulator (sometimes referred to as an O-antigen co-polymerase) normally interacts with Wzy to confer a distinctive modal chain length distribution. The resultant polysaccharide is transferred from the membrane anchor to the lipid A-core oligosaccharide by EC 2.4.99.26, O-antigen ligase, forming a complete lipopolysaccharide structure. There is an enormous diversity of O antigen polymerases with different specificities, reflecting the variability in the structure and composition of O-antigens.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Collins, L.V. and Hackett, J. Molecular cloning, characterization, and nucleotide sequence of the rfc gene, which encodes an O-antigen polymerase of Salmonella typhimurium. J. Bacteriol. 173 (1991) 2521-2529. [PMID: 1707412]
2. Woodward, R., Yi, W., Li, L., Zhao, G., Eguchi, H., Sridhar, P.R., Guo, H., Song, J.K., Motari, E., Cai, L., Kelleher, P., Liu, X., Han, W., Zhang, W., Ding, Y., Li, M. and Wang, P.G. In vitro bacterial polysaccharide biosynthesis: defining the functions of Wzy and Wzz. Nat. Chem. Biol. 6 (2010) 418-423. [PMID: 20418877]
3. Kenyon, J.J. and Reeves, P.R. The Wzy O-antigen polymerase of Yersinia pseudotuberculosis O:2a has a dependence on the Wzz chain-length determinant for efficient polymerization. FEMS Microbiol. Lett. 349 (2013) 163-170. [PMID: 24164168]
4. Islam, S.T., Huszczynski, S.M., Nugent, T., Gold, A.C. and Lam, J.S. Conserved-residue mutations in Wzy affect O-antigen polymerization and Wzz-mediated chain-length regulation in Pseudomonas aeruginosa PAO1. Sci. Rep. 3 (2013) 3441. [PMID: 24309320]
5. Islam, S.T. and Lam, J.S. Synthesis of bacterial polysaccharides via the Wzx/Wzy-dependent pathway. Can. J. Microbiol. 60 (2014) 697-716. [PMID: 25358682]
6. Nath, P. and Morona, R. Mutational analysis of the major periplasmic loops of Shigella flexneri Wzy: identification of the residues affecting O antigen modal chain length control, and Wzz-dependent polymerization activity. Microbiology (Reading) 161 (2015) 774-785. [PMID: 25627441]
7. Merino, S., Gonzalez, V. and Tomas, J.M. The first sugar of the repeat units is essential for the Wzy polymerase activity and elongation of the O-antigen lipopolysaccharide. Future Microbiol 11 (2016) 903-918. [PMID: 27357519]