Creatinine is synthesized from

Creatine & CreatinineCreatinine is formed in muscle from creatine phosphate by irreversible, nonenzymatic dehydration, and loss of phosphate. Since the 24-hour urinary excretion of creatinine is propoionate to muscle mass, it provides a measure of whether a complete 24-hour urine specimen has been collected. Glycine, arginine, and methionine all paicipate in creatine biosynthesis. Synthesis of creatine is completed by methylation of guanidinoacetate by S-adenosylmethionine.Ref: Harper&;s Biochemistry; 30th edition; Chapter 30; Conversion of Amino Acids to Specialized Products