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Structure of rhodocetin reveals noncovalently bound heterodimer interface.

ABSTRACT: 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.

SUBMITTER: Paaventhan P

PROVIDER: S-EPMC2253329 | biostudies-literature | 2005 Jan

REPOSITORIES: biostudies-literature

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Structure of rhodocetin reveals noncovalently bound heterodimer interface.

Paaventhan Palasingam P Kong Chunguang C Joseph Jeremiah S JS Chung Max C M MC Kolatkar Prasanna R PR

Protein science : a publication of the Protein Society 20041202 1

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 st ...[more]

PMID: 15576563

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