PURIFICATION, CRYSTALLIZATION, AND PRELIMINARY-X-RAY DIFFRACTION ANALYSES OF THE BACTERIAL CHEMOTAXIS RECEPTOR MODIFYING ENZYMES

Bacterial chemotaxis receptor modifying enzymes from Salmonella typhim urium have been crystallized using microseeding techniques. The crysta ls of the S-adenosyl-L-methionine-dependent methyltransferase, CheR, b elong to the monoclinic space group P2(1) with cell constants a = 55.1 Angstrom, b = 48.1 Angstrom, c = 63.1 Angstrom, beta = 112.3 degrees. The crystals of the catalytic domain of the methylesterase, CheB, bel ong to the trigonal space group P3(2)21 or P3(2)21 with unit cell dime nsions of a = b = 63.4 Angstrom, c = 86.8 Angstrom. Both crystals cont ain one molecule per asymmetric unit and have calculated Matthews' vol umes of 2.4 Angstrom(3)/Da. (C) 1995 Wiley-Liss, Inc.