CRYSTALLIZATION AND PRELIMINARY-X-RAY STRUCTURE-ANALYSIS OF A HYPERTHERMOSTABLE THIOLTRANSFERASE FROM THE ARCHAEON PYROCOCCUS-FURIOSUS

Thioltransferase from the hyperthermophilic archaeon Pyrococcus furios us is a unique protein disulfide oxidoreductase. The recombinant prote in expressed in Escherichia coli was crystallized by the sitting drop vapor diffusion method, using polyethylene glycol 550 monomethyl ether as the precipitant. The crystals belong to the hexagonal space group P6(1)22 or P6(5)22, with unit cell dimensions of a = b = 110.6 Angstro m and c = 68.4 Angstrom and with one monomer in the asymmetric unit. T he crystals diffracted beyond 2.0 Angstrom and a complete native data set was collected to 2.3 Angstrom resolution. The solution of the crys tal structure by multiple isomorphous replacement is in progress. (C) 1997 Academic Press.