The ImmE7 protein, which can bind specifically to the DNase colicin E7
and neutralize its bactericidal activity, has been pu. rifled and cry
stallized in two different crystal forms by vapor diffusion method, Th
e orthorhombic crystals belong to space group I222 or I2(1)2(1)2(1) an
d have unit cell dimensions a = 75.1 Angstrom, b = 50.5 Angstrom, and
c = 45.4 Angstrom. The second form is monoclinic space group P2(1) wit
h cell dimensions a = 29.3 Angstrom, b = 102.7 Angstrom, c = 53.0 Angs
trom, and beta = 91.5 degrees. The orthorhombic crystals diffract to 1
.8 Angstrom resolution, and are suitable for high-resolution X-ray ana
lysis. (C) 1995 Wiley-Liss, Inc.