Characterisation of a mannose-binding C-type lectin from Oxyuranus scutellatus snake venom.
C-type lectins are calcium-dependent sugar binding proteins and are distributed ubiquitously amongst vertebrate organisms. As part of a wider study on Australian snake venom components, we have identified and characterised a C-type lectin from the venom of Oxyuranus scutellatus (Australian coastal taipan) with mannose-binding activity. This protein exhibited a subunit molecular mass of 15 kDa and was found to bind mannose and also bind to and agglutinate erythrocytes in a Ca(2+)-dependent manner. cDNA transcripts coding for C-lectin proteins were cloned and sequenced from six Australian elapid snake species and an antibody generated against the O. scutellatus mannose-binding C-lectin identified C-lectin proteins in the venom of 13 Australian elapid snakes by immunoblotting. Experimental evidence and molecular modelling also suggest that this protein exhibits a unique dimeric structure. This is the first confirmed example of a snake venom C-lectin with mannose-binding activity.
The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Australia.
Stephen T H
ST
Earl
Jonathan
J
Robson
Manuela
M
Trabi
John
J
de Jersey
Paul P
PP
Masci
Martin F
MF
Lavin
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004546:Elapid Venoms / Q000235:genetics*; D017815:Elapidae / Q000235:genetics; D037601:Mannose-Binding Lectin / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D013045:Species Specificity; D013379:Substrate Specificity
D000906:Antibodies; D018076:DNA, Complementary; D004546:Elapid Venoms; D037601:Mannose-Binding Lectin