Crystallization and preliminary X-ray crystallographic analysis of extracellular giant hemoglobin from pogonophoran Oligobrachia mashikoi

An extracellular giant hemoglobin of Oligobrachia mashikoi, composed of 24 globins with the molecular mass of similar to 400 kDa was crystallized in its intact form. Two crystal forms were obtained by the vapor-diffusion method. Form I crystals obtained using sodium acetate as a precipitant belong to the space group P6(1)22 or P6(5)22, with unit-cell parameters a = 112.41, c = 621.25 angstrom, and diffracted X-rays beyond 3.0 angstrom resolution. Form II crystals obtained using PEG 10000 as a precipitant belong to the space group R32, with unit-cell parameters a = 111.50, c = 276.84 angstrom, and diffracted X-rays beyond 2.9 angstrom resolution. The crystals are suitable for X-ray crystallography to determine the supramacromolecular assembly of this giant hemoglobin. (c) 2005 Elsevier B.V. All rights reserved.