Crystallization and preliminary X-ray diffraction studies of formylmethanofuran: tetrahydromethanopterin...

Formylmethanofuran:tetrahydromethanopterin formyltransferase from the hyperthermophilic methanogenic Archaeon Methanopyrus kandleri (growth temperature optimum 98 degrees C) was crystallized by vapor diffusion methods. Crystal form M obtained with 2-methyl-2,4-pentanediol as precipitant displayed the space group P2(1) with unit cell parameters of a = 87.0 A, b = 75.4 A, c = 104.7 A, and beta = 113.9 degrees and diffracted better than 2 A resolution. Crystal form P grown from polyethylene glycol 8000 belonged to the space group I4(1)22 and had unit cell parameters of 157.5 A and 242.1 A. Diffraction data to 1.73 A were recorded. Crystal form S which was crystallized from (NH4)2SO4 in the space group I4(1)22 with unit cell parameters of 151.3 A and 249.5 A diffracted at least to 2.2 A resolution. All crystal forms probably have four molecules per asymmetric unit and are suitable for X-ray structure analysis.