Effect of pH on malonyl-CoA inhibition of carnitine palmitoyltransferase I.
نویسندگان
چکیده
Malonyl-CoA inhibition of carnitine palmitoyltransferase I was found to be very pH-dependent. Malonyl-CoA concentrations causing 50% inhibition (I50) at pH 6.0, 6.5, 7.0, 7.5 and 8.0 were 0.04, 1, 9, 40 and 200 microM respectively. It is suggested that a lowering of intracellular pH, such as might occur in ketoacidosis, may attenuate hepatic fatty acid oxidation by increasing malonyl-CoA sensitivity of carnitine palmitoyltransferase I.
منابع مشابه
Effects of pH on the interaction of substrates and malonyl-CoA with mitochondrial carnitine palmitoyltransferase I.
The kinetics of carnitine palmitoyltransferase I (CPT I; EC 2.3.1.21) were examined in mitochondria from rat liver, heart and skeletal muscle as a function of pH over the range 6.8-7.6. In all three tissues raising the pH resulted in a fall in the Km for carnitine, no change in the Km for palmitoyl-CoA or Octanoyl-CoA, and a marked decrease in the inhibitory potency of malonyl-CoA. Studies with...
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 212 2 شماره
صفحات -
تاریخ انتشار 1983