Human creatine kinase. Isoenzymes and logistics of energy distribution.
A simple procedure to estimate creatine kinase of mitochondrial origin (CK-mit) was tested in homogenates from human myocardial and skeletal muscle. Thereafter CK-mit was estimated as the difference between the activity remaining after immunoinhibition with anit-CK-M and chromatographic isolation of CK-MB. This method was applied to selected human myocardial and skeletal muscle biopsies. These biopsies were selected on the basis of citrate synthetase activity so as to give a large range in oxidative capacity. CK-MB and CK-mit were correlated and both CK-MB and CK-mit correlated to citrate synthetase activity. The isoenzymes CK-MB and CK-mit were thus associated with the oxidative capacity of the tissue. The results confirm the energy shuttle hypothesis for CK with CK-MB located at target organelles.
D002950:Citrate (si)-Synthase / Q000378:metabolism; D003402:Creatine Kinase / Q000302:isolation & purification / Q000378:metabolism*; D004734:Energy Metabolism; D006801:Humans; D007527:Isoenzymes; D008929:Mitochondria, Heart / Q000201:enzymology; D008931:Mitochondria, Muscle / Q000201:enzymology
D007527:Isoenzymes; D002950:Citrate (si)-Synthase; D003402:Creatine Kinase