Structure of rhodocetin reveals noncovalently bound heterodimer interface.
Rhodocetin is a unique heterodimer consisting of alpha- and beta-subunits of 133 and 129 residues, respectively. The molecule, purified from the crude venom of the Malayan pit viper, Calloselasma rhodostoma, functions as an inhibitor of collagen-induced aggregation. Rhodocetin has been shown to have activity only when present as a dimer. The dimer is formed without an intersubunit disulfide bridge, unlike all the other Ca(2+)-dependent lectin-like proteins. We report here the 1.9 A resolution structure of rhodocetin, which reveals the compensatory interactions that occur in the absence of the disulfide bridge to preserve activity.
Paaventhan
Palasingam
P
Genome Institute of Singapore, Singapore 138672.
Kong
Chunguang
C
Joseph
Jeremiah S
JS
Chung
Max C M
MC
Kolatkar
Prasanna R
PR
D000595:Amino Acid Sequence; D000818:Animals; D003435:Crotalid Venoms / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019281:Dimerization; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000502:physiology; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
D003435:Crotalid Venoms; D021122:Protein Subunits; C119730:rhodocetin