The Structure of Clostridium perfringens NanI Sialidase and Its Catalytic Intermediates

Clostridium perfringens is a Gram-positive bacterium responsible for bacteremia, gas gangrene, and occasionally food poisoning. Its genome encodes three sialidases, nanH, nanI, and nanJ, that are involved in the removal of sialic acids from a variety of glycoconjugates and that play a role in bacter...

Full description

Saved in:
Bibliographic Details
Published inThe Journal of biological chemistry Vol. 283; no. 14; pp. 9080 - 9088
Main Authors Newstead, Simon L., Potter, Jane A., Wilson, Jennifer C., Xu, Guogang, Chien, Chin-Hsiang, Watts, Andrew G., Withers, Stephen G., Taylor, Garry L.
Format Journal Article
LanguageEnglish
Published United States Elsevier Inc 04.04.2008
American Society for Biochemistry and Molecular Biology
Subjects
Bacteremia - enzymology
Catalysis
Clostridium perfringens
Clostridium perfringens - enzymology
Clostridium perfringens - pathogenicity
Crystallography, X-Ray
Enzyme Catalysis and Regulation
Foodborne Diseases - enzymology
Gas Gangrene - enzymology
Glycoconjugates - chemistry
Glycoconjugates - metabolism
Humans
Neuraminidase - chemistry
Nuclear Magnetic Resonance, Biomolecular
Protein Structure, Tertiary
Sialic Acids - chemistry
Sialic Acids - metabolism
Online AccessGet full text

Cover

More Information
Summary:Clostridium perfringens is a Gram-positive bacterium responsible for bacteremia, gas gangrene, and occasionally food poisoning. Its genome encodes three sialidases, nanH, nanI, and nanJ, that are involved in the removal of sialic acids from a variety of glycoconjugates and that play a role in bacterial nutrition and pathogenesis. Recent studies on trypanosomal (trans-) sialidases have suggested that catalysis in all sialidases may proceed via a covalent intermediate similar to that of other retaining glycosidases. Here we provide further evidence to support this suggestion by reporting the 0.97Å resolution atomic structure of the catalytic domain of the C. perfringens NanI sialidase, and complexes with its substrate sialic acid (N-acetylneuramic acid) also to 0.97Å resolution, with a transition-state analogue (2-deoxy-2,3-dehydro-N-acetylneuraminic acid) to 1.5Å resolution, and with a covalent intermediate formed using a fluorinated sialic acid analogue to 1.2Å resolution. Together, these structures provide high resolution snapshots along the catalytic pathway. The crystal structures suggested that NanI is able to hydrate 2-deoxy-2,3-dehydro-N-acetylneuraminic acid to N-acetylneuramic acid. This was confirmed by NMR, and a mechanism for this activity is suggested.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
Present address: Dept. of Pharmacy and Pharmacology, University of Bath, Bath BA2 7AY, UK.
To whom correspondence should be addressed: Centre for Biomolecular Sciences, University of St. Andrews, St. Andrews, Fife KY16 9ST, UK. Tel.: 44-1334-467301; Fax: 44-1334-462595; E-mail: glt2@st-andrews.ac.uk.
This work was supported by the Biotechnology and Biological Sciences Research Council and the Royal Society of Edinburgh. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Present address: Division of Molecular Biosciences, Membrane Protein Crystallography Group, Imperial College London, London SW7 2AZ, UK.
The atomic coordinates and structure factors (codes 2vk5, 2vk6, 2vk7) have been deposited in the Protein Data Bank, Research Collaboratory for Structural Bioinformatics, Rutgers University, New Brunswick, NJ (http://www.rcsb.org/).
ISSN:0021-9258
1083-351X
DOI:10.1074/jbc.M710247200