Crystallization and Preliminary X-ray Analysis of the Low Molecular Weight Phosphotyrosyl Protein Phosphatase from Bovine Heart

Abstract

Two crystal forms of bovine heart phosphotyrosyl protein phosphatase (BHPTP) have been examined by X-ray analysis. One crystal form grows as long rods with triclinic crystal symmetry and diffracts to 3 Å resolution. The diffraction pattern of this form of the crystal shows twinning about a major axis. A second crystal form of BHPTP grows as flat trapezoidal prisms with monoclinic symmetry C2, and unit cell parameters a = 95·3 Å, b = 43·3 Å, c = 41·2 Å and β = 113·5°. The unit cell dimensions indicate that there is one 18 kDa molecule per asymmetric unit. These crystals diffract to at least 2·2 Å resolution and are resistant to decay in the X-ray beam.