Crystallization, activity assay and preliminary X-ray diffraction analysis of the uncleaved form of the serpin antichymotrypsin.
Crystals of recombinant wild-type antichymotrypsin have been prepared by the method of vapor diffusion with polyethylene glycol 4000 as a precipitant at pH 5.7. Two crystal forms are observed. One form belongs to tetragonal space group P4(3)2(1)2 (or P4(1)2(1)2) and has unit cell dimensions a = b = 126 A, c = 243 A, with two molecules in the asymmetric unit. The other crystal form belongs to orthorhombic space group P2(1)2(1)2(1) and has unit cell parameters of a = 73 A, b = 78 A and c = 80 A, with one molecular in the asymmetric unit. Diffraction intensity measurements have been made on the tetragonal crystal form to a limiting resolution of 4.1 A, and reflections have been observed on X-ray still photographs to a limiting resolution of 2.5 A for the orthorhombic form. An activity assay of redissolved tetragonal form crystals indicates that the uncleaved, functional serpin has been crystallized.
Wei
A
A
Department of Chemistry, University of Pennsylvania, Philadelphia 19104.
Rubin
H
H
Cooperman
B S
BS
Schechter
N
N
Christianson
D W
DW
D002918:Chymotrypsin / Q000378:metabolism; D003460:Crystallization; D007700:Kinetics; D046911:Macromolecular Substances; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D014961:X-Ray Diffraction; D000514:alpha 1-Antichymotrypsin / Q000737:chemistry* / Q000378:metabolism*
D046911:Macromolecular Substances; D011994:Recombinant Proteins; D000514:alpha 1-Antichymotrypsin; D002918:Chymotrypsin