Crystallization and preliminary X-ray crystallographic studies on Type III antifreeze protein

Abstract
Type III antifreeze protein, more specifically the recombinant QAE-Sephadex-binding isoform, has been crystallized in 50–55% saturated ammonium sulfate, 0.1 M sodium acetate, pH 4.0–4.5. The resultant crystals belong to the ortho-rhombic space group P212121 with a = 32.60 Å, b = 39.00 Å, and c = 46.57 Å and diffract to at least 1.7 Å. A set of 1.7-Å native data has been collected, with completeness 93.4% and Rsvm of 0.069. Initial screening for heavy-atom derivatives has yielded a Pt-bound derivative.