Please use this identifier to cite or link to this item:
Title: Group D prothrombin activators from snake venom are structural homologues of mammalian blood coagulation factor Xa
Authors: Rao, V.S.
Joseph, J.S.
Kini, R.M. 
Keywords: Hopsarin D
Notanarin D
Notecarin D
Serine proteinase
Issue Date: 1-Feb-2003
Citation: Rao, V.S., Joseph, J.S., Kini, R.M. (2003-02-01). Group D prothrombin activators from snake venom are structural homologues of mammalian blood coagulation factor Xa. Biochemical Journal 369 (3) : 635-642. ScholarBank@NUS Repository.
Abstract: Procoagulant venoms of several Australian elapids contain proteinases that specifically activate prothrombin; among these, Group D activators are functionally similar to coagulation factor Xa (FXa). Structural information on this class of prothrombin activators will contribute significantly towards understanding the mechanism of FXa-mediated prothrombin activation. Here we present the purification of Group D prothrombin activators from three Australian snake venoms (Hoplocephalus stephensi, Notechis scutatus scutatus and Notechis ater niger) using a single-step method, and their N-terminal sequences. The N-terminal sequence of the heavy chain of hopsarin D (H. stephensi) revealed that a fully conserved Cys-7 was substituted with a Ser residue. We therefore determined the complete amino acid sequence of hopsarin D. Hopsarin D shows ≈ 70% similarity with FXa and ≈ 98% similarity with trocarin D, a Group D prothrombin activator from Tropidechis carinatus. It possesses the characteristic Gla domain, two epidermal growth factor-like domains and a serine proteinase domain. All residues important for catalysis are conserved, as are most regions involved in interactions with factor Va and prothrombin. However, there are some structural differences. Unlike FXa, hopsarin D is glycosylated in both its chains: in light-chain residue 52 and heavy-chain residue 45. The glycosylation on the heavy chain is a large carbohydrate moiety adjacent to the active-site pocket. Overall, hopsarin D is structurally and functionally similar to mammalian coagulation FXa.
Source Title: Biochemical Journal
ISSN: 02646021
DOI: 10.1042/BJ20020889
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.


checked on Sep 26, 2022


checked on Sep 26, 2022

Page view(s)

checked on Sep 22, 2022

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.