title: Crystal structure of subtilisin DY, a random mutant of subtilisin Carlsberg.
abstract: The crystal structure of subtilisin DY inhibited by N-benzyloxycarbonyl-Ala-Pro-Phe-chloromethyl ketone has been solved by molecular replacement with subtilisin Carlsberg as the starting model. The model has been refined to a crystallographic R factor (= sigma absolute value [(absolute value Fo) - (absolute value Fc)] / sigma (absolute value of Fo) of 15.1% using X-ray diffraction data to 0.175 nm resolution. Subtilisin DY is an alkaline proteinase from the X-irradiated Japanese strain DY of Bacillus licheniformis, which normally produces subtilisin Carlsberg. It has very similar properties to subtilisin Carlsberg, with a slightly enhanced resistance to heat and guanidine hydrochloride-induced denaturation, in spite of the fact that the sequences of the two enzymes differ in 31 positions out of 274 residues. The close similarity in overall three-dimensional structure of subtilisins DY and Carlsberg and also their physicochemical properties, such as activity and stability, shows that nature aided by X-irradiation for rapid 'evolution' is able to accommodate considerable changes in sequence without substantial changes in property.
authors.affiliation: European Molecular Biology Laboratory, Institute of Physiological Chemistry, Hamburg, Germany. Susanna@unisgi1.desy.de
authors.forename: S
authors.initials: S
authors.lastname: Eschenburg
authors.forename: N
authors.initials: N
authors.lastname: Genov
authors.forename: K
authors.initials: K
authors.lastname: Peters
authors.forename: S
authors.initials: S
authors.lastname: Fittkau
authors.forename: S
authors.initials: S
authors.lastname: Stoeva
authors.forename: K S
authors.initials: KS
authors.lastname: Wilson
authors.forename: C
authors.initials: C
authors.lastname: Betzel
mesh_terms: D000595:Amino Acid Sequence; D002384:Catalysis; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008670:Metals / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013381:Subtilisins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D008670:Metals; D013381:Subtilisins