Open AccessEvidence that the lizard helospectin peptides are O‐glycosylated
Author(s) -
VandermeersPiret MarieClaire,
Vandermeers André,
Gourlet Philippe,
Ali Mohamed H.,
Waelbroeck Magali,
Robberecht Patrick
Publication year - 2000
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1327.2000.01506.x
Subject(s) - edman degradation , chemistry , biochemistry , peptide , glycosylation , peptide sequence , hexose , residue (chemistry) , receptor , biology , enzyme , gene
Six forms of helospectin (a vasoactive intestinal peptide analogue) were purified from the venom of the Heloderma horridum lizard. Their identification was performed by combining sequencing by automated Edman degradation and electrospray mass spectrometry analysis on the complete peptides and their tryptic fragments. The products resulting from the action of an O‐glycosidase were also analysed. Two forms were identified as the previously named Hs1 and Hs2 of 38 and 37 amino‐acid residues, respectively. Two forms corresponded to Hs1 and Hs2 O‐glycosylated by a N ‐acetylhexosamine‐hexose motif attached to the Ser32 residue. Two other forms were not completely characterized but might correspond to the O‐glycosylated forms bearing a phosphate or a sulfate group. The glycosylation did not affect the capacity of the helospectins to recognize and to activate the human and the rat VPAC 1 and VPAC 2 receptors.