Crystallization and preliminary crystallographic analysis of the fourth FAS1 domain of human BigH3

The protein BigH3 is a cell‐adhesion molecule induced by transforming growth factor‐β (TGF‐β). It consists of four homologous repeat domains known as FAS1 domains; mutations in these domains have been linked to corneal dystrophy. The fourth FAS1 domain was expressed in Escherichia coli B834 (DE3) (a methionine auxotroph) and purified by DEAE anion‐exchange and gel‐filtration chromatography. The FAS1 domain was crystallized using the vapour‐diffusion method. A SAD diffraction data set was collected to a resolution of 2.5 Å at 100 K. The crystal belonged to space group P 6 1 or P 6 5 and had two molecules per asymmetric unit, with unit‐cell parameters a = b = 62.93, c  = 143.27 Å, α = β = 90.0, γ = 120.0°.