On the catalytic mechanism of polysaccharide lyases: evidence of His and Tyr involvement in heparin lysis by heparinase I and the role of Ca2+

Córdula, Carolina R.; Lima, Marcelo A.; Shinjo, Samuel K.; Gesteira, Tarsis F.; Pol-Fachin, Laércio; Coulson-Thomas, Vivien J.; Verli, Hugo; Yates, Edwin A.; Rudd, Timothy R.; Pinhal, Maria A. S.; Toma, Leny; Dietrich, Carl P.; Nader, Helena B.; Tersariol, Ivarne L. S.

Abstract

The structurally diverse polysaccharide lyase enzymes are distributed from plants to animals but share common catalytic mechanisms. One, heparinase I (F. heparinum), is employed in the production of the major anticoagulant drug, low molecular weight heparin, and is a mainstay of cell surface proteoglycan analysis. We demonstrate that heparinase I specificity and efficiency depend on the cationic form of the substrate. Ca2+–heparin, in which α-L-iduronate-2-O-sulfate residues adopt 1C4 conformation preferentially, is a substrate, while Na+–heparin is an inhibitor. His and Tyr residues are identified in the catalytic step and a model based on molecular dynamics and docking is proposed, in which deprotonated His203 initiates β-elimination by abstracting the C5 proton of the α-L-iduonate-2-O-sulfate residue in the substrate, and protonated Tyr357 provides the donor to the hexosamine leaving group.

Citation

Córdula, C. R., Lima, M. A., Shinjo, S. K., Gesteira, T. F., Pol-Fachin, L., Coulson-Thomas, V. J., …Tersariol, I. L. S. (2013). On the catalytic mechanism of polysaccharide lyases: evidence of His and Tyr involvement in heparin lysis by heparinase I and the role of Ca2+. Molecular BioSystems, 10(1), 54-64. https://doi.org/10.1039/C3MB70370C

• Journal Article Type: Article
• Publication Date: Oct 31, 2013
• Deposit Date: May 31, 2023
• Journal: Molecular BioSystems
• Print ISSN: 1742-206X
• Electronic ISSN: 1742-2051
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 1
• Pages: 54-64
• DOI: https://doi.org/10.1039/C3MB70370C
• Keywords: Molecular Biology; Biotechnology
• Publisher URL: https://pubs.rsc.org/en/content/articlehtml/2014/mb/c3mb70370c