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Crystallization and preliminary X-ray diffraction analysis of hemextin A: a unique anticoagulant protein from Hemachatus haemachatus venom.

ABSTRACT: Hemextin A was isolated and purified from African Ringhals cobra (Hemachatus haemachatus). It is a three-finger toxin that specifically inhibits blood coagulation factor VIIa and clot formation and that also interacts with hemextin B to form a unique anticoagulant complex. Hemextin A was crystallized by the hanging-drop vapour-diffusion method by equilibration against 0.2 M ammonium acetate, 0.1 M sodium acetate trihydrate pH 4.6 and 30% PEG 4000 as the precipitating agent. The crystals belong to space group P2(1)2(1)2(1), with unit-cell parameters a = 49.27, b = 49.51, c = 57.87 A and two molecules in the asymmetric unit. They diffracted to 1.5 A resolution at beamline X25 at BNL.

SUBMITTER: Banerjee Y

PROVIDER: S-EPMC2335159 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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Crystallization and preliminary X-ray diffraction analysis of hemextin A: a unique anticoagulant protein from Hemachatus haemachatus venom.

Banerjee Yajnavalka Y Kumar Sundramurthy S Jobichen Chacko C Kini R Manjunatha RM

Acta crystallographica. Section F, Structural biology and crystallization communications 20070721 Pt 8

Hemextin A was isolated and purified from African Ringhals cobra (Hemachatus haemachatus). It is a three-finger toxin that specifically inhibits blood coagulation factor VIIa and clot formation and that also interacts with hemextin B to form a unique anticoagulant complex. Hemextin A was crystallized by the hanging-drop vapour-diffusion method by equilibration against 0.2 M ammonium acetate, 0.1 M sodium acetate trihydrate pH 4.6 and 30% PEG 4000 as the precipitating agent. The crystals belong t ...[more]

PMID: 17671372

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Biophysical characterization of anticoagulant hemextin AB complex from the venom of snake Hemachatus haemachatus.

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Crystallization and preliminary X-ray diffraction analysis of an L-amino-acid oxidase from Bothrops jararacussu venom.

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Purification, crystallization and preliminary X-ray diffraction analysis of saxthrombin, a thrombin-like enzyme from Gloydius saxatilis venom.

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