Interaction of Neisseria meningitidis group X N-acetylglucosamine-1-phosphotransferase with its donor substrate
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Authors
Ming, Shonoi A.
Cottman-Thomas, Ebony
Black, Natalee C.
Chen, Yi
Veeramachineni, Vamsee
Peterson, Dwight C.
Chen, Xi
Tedaldi, Lauren M.
Wagner, Gerd K.
Cai, Chao
Issue Date
2018-02-01
Type
Article
Language
ENG
Keywords
Biology , Chemistry and chemical biology , Chemical and biological engineering , Biomedical engineering
Alternative Title
Abstract
Neisseria meningitidis Group X is an emerging cause of bacterial meningitis in Sub-Saharan Africa. The capsular polysaccharide of Group X is a homopolymer of N-acetylglucosamine α(1–4) phosphate and is a vaccine target for prevention of disease associated with this meningococcal serogroup. We have demonstrated previously that the formation of the polymer is catalyzed by a phosphotransferase which transfers N-acetylglucosamine-1-phosphate from UDP-N-acetylglucosamine to the 4-hydroxyl of the N-acetylglucosamine on the nonreducing end of the growing chain. In this study, we use substrate analogs of UDP-GlcNAc to define the enzyme/donor substrate interactions critical for catalysis. Our kinetic analysis of the phosphotransferase reaction is consistent with a sequential mechanism of substrate addition and product release. The use of novel uracil modified analogs designed by Wagner et al. enabled us to assess whether the CsxA-catalyzed reaction is consistent with a donor dependent conformational change. As expected with this model for glycosyltransferases, UDP-GlcNAc analogs with bulky uracil modifications are not substrates but are inhibitors. An analog with a smaller iodo uracil substitution is a substrate and a less potent inhibitor. Moreover, our survey of analogs with modifications on the N-acetylglucosamine residue of the sugar nucleotide donor highlights the importance of substituents at C2 and C4 of the sugar residue. The hydroxyl group at C4 and the structure of the acyl group at C2 are very important for specificity and substrate interactions during the polymerization reaction. While most analogs modified at C2 were inhibitors, acetamido analogs were also substrates suggesting the importance of the carbonyl group.
Description
Glycobiology, 28, 100–107
Note : if this item contains full text it may be a preprint, author manuscript, or a Gold OA copy that permits redistribution with a license such as CC BY. The final version is available through the publisher’s platform.
Note : if this item contains full text it may be a preprint, author manuscript, or a Gold OA copy that permits redistribution with a license such as CC BY. The final version is available through the publisher’s platform.
Full Citation
Interaction of Neisseria meningitidis group X N-acetylglucosamine-1-phosphotransferase with its donor substrate, S. Ming, E. Cottman-Thomas, N. C. Black, Y. Chen, V. Veeramachineni, D. C. Peterson, X. Chen, G. Wagner, C. Cai, R. J. Linhardt, W. F. Vann, Glycobiology, 28, 100–107, 2018.
Publisher
Oxford University Press
Terms of Use
Journal
Volume
Issue
PubMed ID
DOI
ISSN
14602423
9596658
9596658