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-beta (TGF-beta). 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 A at 100 K. The crystal belonged to space group P6(1) or P6(5) and had two molecules per asymmetric unit, with unit-cell parameters a = b = 62.93, c = 143.27 A, alpha = beta = 90.0, gamma = 120.0 degrees.