Acceptor Specificity of the Pasteurella Hyaluronan and Chondroitin Synthases and Production of Chimeric Glycosaminoglycans
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Authors
Tracy, Breca S.
Avci, Fikri Y.
Linhardt, Robert J.
DeAngelis, Paul L.
Issue Date
2007-01-05
Type
Article
Language
ENG
Keywords
Biology , Chemistry and chemical biology , Chemical and biological engineering , Biomedical engineering
Alternative Title
Abstract
The hyaluronan (HA) synthase, PmHAS, and the chondroitin synthase, PmCS, from the Gram-negative bacterium Pasteurella multocida polymerize the glycosaminoglycan (GAG) sugar chains HA or chondroitin, respectively. The recombinant Escherichia coli-derived enzymes were shown previously to elongate exogenously supplied oligosaccharides of their cognate GAG (e.g. HA elongated by PmHAS). Here we show that oligosaccharides and polysaccharides of certain noncognate GAGs (including sulfated and iduronic acid-containing forms) are elongated by PmHAS (e.g. chondroitin elongated by PmHAS) or PmCS. Various acceptors were tested in assays where the synthase extended the molecule with either a single monosaccharide or a long chain (approximately 10(2-4) sugars). Certain GAGs were very poor acceptors in comparison to the cognate molecules, but elongated products were detected nonetheless. Overall, these findings suggest that for the interaction between the acceptor and the enzyme (a) the orientation of the hydroxyl at the C-4 position of the hexosamine is not critical, (b) the conformation of C-5 of the hexuronic acid (glucuronic versus iduronic) is not crucial, and (c) additional negative sulfate groups are well tolerated in certain cases, such as on C-6 of the hexosamine, but others, including C-4 sulfates, were not or were poorly tolerated. In vivo, the bacterial enzymes only process unsulfated polymers; thus it is not expected that the PmCS and PmHAS catalysts would exhibit such relative relaxed sugar specificity by acting on a variety of animal-derived sulfated or epimerized GAGs. However, this feature allows the chemoenzymatic synthesis of a variety of chimeric GAG polymers, including mimics of proteoglycan complexes.
Description
Journal of Biological Chemistry, 282, 337–344
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
Acceptor Specificity of the Pasteurella Hyaluronan and Chondroitin Synthases and Production of Chimeric Glycosaminoglycans, B. S. Tracy, F. Y. Avci, Robert J. Linhardt, and P. L. DeAngelis, Journal of Biological Chemistry, 282, 337–344, 2007.
Publisher
Elsevier
Terms of Use
Journal
Volume
Issue
PubMed ID
DOI
ISSN
1083351X
219258
219258