Crystallization and preliminary X-ray analysis of the Mj0684 gene product, a putative aspartate aminotransferase, from Methanococcus jannaschii

Abstract

A putative aspartate aminotransferase from the hyperthermophilic archaeon Methanococcus jannaschii encoded by the Mj0684 gene has been overexpressed in Escherichia coli and crystallized at 296 Kusing the sitting-drop vapour-diffusion method. The crystals belong to space group P4(1)2(1)2 (or P4(3)2(1)2), with unit-cell parameters a = b = 111.87, c = 60.86 Angstrom. They diffract to 2.2 Angstrom resolution using Cu Kalpha X-rays. The asymmetric unit contains a single subunit of the recombinant Mj0684 gene product, giving a corresponding V-M of 2.25 Angstrom(3) Da(-1) and a solvent content of 45.3% by volume. An X-ray diffraction data set has been collected to 2.2 Angstrom at 295 K.