The pH sensitivity of H 2 O 2 metabolism in skeletal muscle mitochondria

O + + H 2 O „ + M ... \ H 5 O 2 + „ + M ...

4-Methyl-2-oxopentanoate oxidation by rat skeletal-muscle mitochondria.

1. Oxidative decarboxylation of 4-methyl-2-oxopentanoate (2-oxoisocaproate) by mitochondria of rat skeletal muscle showed biphasic kinetics. Two apparent Km values of 9.1 micronM and 0.78 mM were established. In broken mitochondria the rate of oxidation was lower and only the higher apparent Km value was found. 2. Isovalerylcarnitine inhibited 4-methyl-2-oxopentanoate oxidation in the presence ...

Kinetics of HO 2 + HO 2 ! H 2 O 2 + O 2 : Implications for Stratospheric H

[1] The reaction HO2 + HO2 ! H2O2 + O2 (1) has been studied at 100 Torr and 222 K to 295 K. Experiments employing photolysis of Cl2/CH3OH/O2/N2 and F2/H2/O2/N2 gas mixtures to produce HO2 confirmed that methanol enhanced the observed reaction rate. At 100 Torr, zero methanol, k1 = (8.8 ± 0.9) 10 13 exp[(210 ± 26)/T] cm molecule 1 s 1 (2s uncertainties), which agrees with current recommendations...

H(2)O(2)-induced kinetic and chemical modifications of smooth muscle myosin: correlation to effects of H(2)O(2) on airway smooth muscle.

The effect of H(2)O(2) on smooth muscle heavy meromyosin (HMM) and subfragment 1 (S1) was examined. The number of molecules that retained the ability to bind ATP and the actinactivated rate of P(i) release were measured by single-turnover kinetics. H(2)O(2) treatment caused a decrease in HMM regulation from 800- to 27-fold. For unphosphorylated and phosphorylated heavy meromyosin and for S1, ap...

Role of PKCδ in Insulin Sensitivity and Skeletal Muscle Metabolism

Protein kinase C (PKC)δ has been shown to be increased in liver in obesity and plays an important role in the development of hepatic insulin resistance in both mice and humans. In the current study, we explored the role of PKCδ in skeletal muscle in the control of insulin sensitivity and glucose metabolism by generating mice in which PKCδ was deleted specifically in muscle using Cre-lox recombi...