Novel creatine amidinohydrolase, production thereof and use thereof

摘要

A creatine amidinohydrolase having the following physicochemical properties: Action: catalyzing the following reaction; creatine + H2O -> sarcosine + urea Optimum temperature: about 40 - 50 DEG C Optimum pH: pH about 8.0 - 9.0 Heat stability: not more than about 50 DEG C (pH 7.5, 30 min) Km value for creatine in a coupling assay using a sarcosine oxidase and a peroxidase: about 3.5 - 10.0 mM Molecular weight: about 43,000 (SDS-PAGE) Isoelectric point: about 3.5, a method for producing said enzyme, comprising culture of microorganism producing said enzyme, a method for the determination of creatine or creatinine in a sample using said enzyme, and a reagent therefor. According to the present invention, a creatine amidinohydrolase having a smaller Km value than that of the conventionally known creatine amidinohydrolase can be produced in an industrially large amount, and can be used as a routine reagent for clinical tests for determining creatine and creatinine in biological samples.