Conversion of the cleavage specificity of subtilisin YaB on oxidized insulin chains to an elastase-like specificity by replacement of Gly124 with Ala.
Replacement of Gly124 on the S1 pocket of subtilisin YaB with Ala changed the cleavage pattern on oxidized insulin B-chain from the subtilisin type to the elastase type. The initial cleavage site in the B-chain shifted from L15-Y16 for wild-type YaB to A14-L15 for the G124A mutant. Upon complete hydrolysis with the G124A mutant, four of the six major cleavage sites on the B-chain were identical to porcine pancreatic elastase cleavage sites.
Mei
Hui-Ching
HC
Institute of Biochemistry, National Yang-Ming University, Taipei, Taiwan, ROC.
Li
Ywan-Feng
YF
Hsu
Chi-Cheng
CC
Tsai
Ying-Chieh
YC
Takagi
Hiroshi
H
D000409:Alanine / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics*; D005998:Glycine / Q000235:genetics*; D007328:Insulin / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D010084:Oxidation-Reduction; D010196:Pancreatic Elastase / Q000378:metabolism*; D017433:Protein Structure, Secondary; D013379:Substrate Specificity; D020860:Subtilisin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D007328:Insulin; D010196:Pancreatic Elastase; D020860:Subtilisin; D000409:Alanine; D005998:Glycine