Creatine Amidinohydrolase (CRH)

Creatine Amidinohydrolase catalyzes the hydrolytic reaction converting creatine to sarcosine and urea. The enzyme is purified from a microorganism. The molecular weight of the enzyme is approximately 67,000. The enzyme is useful for the enzymatic assay of creatine and creatinine when coupled with other related enzymes.The optimal conditions for growing A. ureafaciens for producing maximum amounts of creatinine hydrolase and creatine amidinohydrolase relative to total protein are described. This required a medium in which either creatinine or creatine was the sole source of carbon. The specific activity of a crude, cell-free sonicate of creatinine hydrolase was increased 110- to 140-fold by a series of purification steps including heat treatment which inactivated creatine amidinohydrolase, precipitation of nucleic acids with streptomycin, ammonium sulfate precipitation of inert proteins.