. . . . . "Creatine kinase U-type, mitochondrial" . "KCRU_RAT" . . "Acidic-type mitochondrial creatine kinase" . "Mia-CK" . "U-MtCK" . "2.7.3.2" . "Ubiquitous mitochondrial creatine kinase" . "FUNCTION: Reversibly catalyzes the transfer of phosphate between ATP and various phosphogens (e.g. creatine phosphate). Creatine kinase isoenzymes play a central role in energy transduction in tissues with large, fluctuating energy demands, such as skeletal muscle, heart, brain and spermatozoa. CATALYTIC ACTIVITY: ATP + creatine = ADP + phosphocreatine. SUBUNIT: Exists as an octamer composed of four MTCK homodimers. SUBCELLULAR LOCATION: Mitochondrion inner membrane; Peripheral membrane protein; Intermembrane side. TISSUE SPECIFICITY: In many tissues, with highest levels in brain gut and kidney. In the kidney localized primarily in the outer medulla in the thick ascending limb and distal convoluted tubule. MISCELLANEOUS: Mitochondrial creatine kinase binds cardiolipin. SIMILARITY: Belongs to the ATP:guanido phosphotransferase family. GENE SYNONYMS: Ckmt. COPYRIGHT: Protein annotation is derived from the UniProt Consortium (http://www.uniprot.org/). Distributed under the Creative Commons Attribution-NoDerivs License." .