Catalytic Activity of Tripeptidase from Lactococcus lactis to Which Amino Acid Substitution Was Introduced According to Natural Mutation

Abstract

Four mutations observed between tripeptidases from Lactococcus lactis subsp. lactis and subsp. cremoris were introduced one by one to the corresponding points in wild-type tripeptidase from L. lactis subsp. lactis. The k _cat values of four resultant mutants were analyzed and discussed in stereographical terms. Change in catalytic activity appeared to be related to the sequential and steric location of mutation point within the enzyme protein, even though no drastic change was observed with one point mutation.

• catalytic activity
• point mutation
• tripeptidase
• PepT
• Lactococcus lactis