Purification and Molecular Cloning of Arginine Kinase from Tail Muscle of Crayfish, Procambarus Clarkii.

Abstract

We have purified adenosine triphosphate: arginine phosphotransferase (EC2-7-3-3, arginine kinase) and molecularly cloned the cDNA from the tail muscle of crayfish, Procambarus clarkii. An open reading frame encodes 357 amino acid residues with a calculated molecular mass of 40, 118 dalton. The predicted amino acid sequence shows 60% similarity with that of human creatine kinase B-subunit. The expression of a full-length cDNA in COS7 cells gave rise to a product of 40kDa and conferred the arginine kinase activity on mammalian cells. The amino acid sequence surrounding cys271 is well conserved as an active site for the catalytic function among a family of phosphagen kinase. We have found that chemical modification of a single cysteinyl residue of arginine kinase inhibits the enzymatic function and ATP protects the enzyme against this modification.