Cloning, expression, purification, crystallization and preliminary X‐ray diffraction analysis of an ASCH domain‐containing protein from Zymomonas mobilis ZM4

The human activating signal cointegrator 1 (ASC‐1) homology (ASCH) domain is frequently observed in many organisms, although its function has not yet been clearly defined. In Zymomonas mobilis ZM4, the ZMO0922 gene encodes a polypeptide that includes an ASCH domain (zmASCH). To provide a better structural background for the probable role of ASCH domain‐containing proteins, the ZMO0922 gene was cloned and expressed. The purified protein was crystallized from 30%( w / v ) polyethylene glycol 400, 0.1  M cacodylic acid pH 6.5 and 0.2  M lithium sulfate. Diffraction data were collected to 2.1 Å resolution using synchrotron radiation. The crystal belonged to the primitive trigonal space group P 3 1 21 or P 3 2 21, with unit‐cell parameters a = b = 51.67, c = 207.30 Å, α = β = 90, γ = 120°. Assuming the presence of one molecule in the asymmetric unit gave a Matthews coefficient of 4.69 Å 3  Da −1 , corresponding to a solvent content of 73.7%.