Open Access1 H‐NMR studies and secondary structure of the RGD‐containing snake toxin, albolabrin
Author(s) -
JASEJA Mahesh,
SMITH K. John,
LU Xinjie,
WILLIAMS Janice A.,
TRAYER Hylary,
TRAYER Ian P.,
HYDE Eva I.
Publication year - 1993
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1993.tb18441.x
Subject(s) - homonuclear molecule , intramolecular force , protein secondary structure , chemistry , snake venom , stereochemistry , peptide , sequence (biology) , nuclear magnetic resonance spectroscopy , crystallography , biophysics , venom , biochemistry , molecule , biology , organic chemistry
Albolabrin is a naturally occurring peptide from snake venom containing the sequence Arg‐Gly‐Asp (RGD). It inhibits platelet aggregation by blocking the binding of fibrinogen to the glycoprotein Gp IIb‐IIIa, on the surface of activated platelets. Albolabrin consists of 73 residues with six intramolecular disulphide bonds. The 1 H‐NMR spectrum of albolabrin has been assigned using homonuclear two‐dimensional techniques and its secondary structure determined. Like kistrin and echistatin, two related peptides from snake venom, albolabrin appears to have little regular secondary structure in solution. Several bends and two short distorted β sheets are observed. The RGD sequence, important for binding to the receptor, lies in a mobile loop joining two strands of one of these β sheets. This loop undergoes a pH‐dependent conformational change.