title: Crystallization and preliminary X-ray crystallographic studies of a psychrophilic subtilisin-like protease Apa1 from Antarctic Pseudoalteromonas sp. strain AS-11.
abstract: The psychrophilic alkaline serine protease Apa1 secreted by the Antarctic psychrotroph Pseudoalteromonas sp. strain AS-11 consists of a subtilisin-like region (293 residues) and an additional insert region (148 residues) that does not show a sequence homology to any proteins in the RCSB Protein Data Bank. Apa1 inhibited with phenylmethanesulfonyl fluoride has been crystallized and X-ray diffraction data have been collected to 1.78 A resolution. The crystals belong to space group C2, with unit-cell parameters a = 122.94, b = 138.48, c = 64.77 A, alpha = gamma = 90, beta = 97.5 degrees. A molecular-replacement solution has been found using the structure of the mesophilic counterpart subtilisin DY with 38% sequence identity to the catalytic domain of Apa1 as a search model. This is the first crystallographic study of a cold-adapted subtilisin-like protease.
authors.affiliation: Department of Applied Biological Sciences, Saga University, Saga 840-8502, Japan.
authors.forename: Danghong
authors.initials: D
authors.lastname: Dong
authors.forename: Tokuo
authors.initials: T
authors.lastname: Ihara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Motoshima
authors.forename: Keiichi
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D000864:Antarctic Regions; D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification; D003460:Crystallization; D018360:Crystallography, X-Ray; D031161:Pseudoalteromonas / Q000201:enzymology*; D013381:Subtilisins / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D013381:Subtilisins