NADH-cytochrome c reductase

Abnormalities of the respiratoiy chain. These are increasingly identified as the hallmark of mitochondrial diseases or mitochondrial encephalomyopathies [13]. They can be identified on the basis of polarographic studies showing differential impairment in the ability of isolated intact mitochondria to use different substrates. For example, defective respiration with NAD-dependent substrates, such as pyruvate and malate, but normal respiration with FAD-dependent substrates, such as succinate, suggests an isolated defect of complex I (Fig. 42-3). However, defective respiration with both types of substrates in the presence of normal cytochrome c oxidase activity, also termed complex IV, localizes the lesions to complex III (Fig. 42-3). Because frozen muscle is much more commonly available than fresh tissue, electron transport is usually measured through discrete portions of the respiratory chain. Thus, isolated defects of NADH-cytochrome c reductase, or NADH-coenzyme Q (CoQ) reductase suggest a problem within complex I, while a simultaneous defect of NADH and succinate-cytochrome c reductase activities points to a biochemical error in complex III (Fig. 42-3). Isolated defects of complex III can be confirmed by measuring reduced CoQ-cytochrome c reductase activity. 

The marker enzymes used in this experiment are as follows vanadate-sensitive H+-ATPase (plasma membrane), nitrate-sensitive H+-ATPase or pyrophosphatase (tonoplast), TritonX-100 stimulated-UDPase or IDPase (Golgi complex), antimycin A-insensitive NADPH cytochrome c reductase (ER), and cytochrome c oxidase (mitochondria inner membrane). NADH cytochrome c reductase activity is found to be 10 times higher than NADPH cytochrome c reductase activity. Chlorophyll content can be measured as the chloroplast marker. The chlorophyll content is calculated by the following equation. Before measurement, auto zero is performed at 750 ran. 

Antimycin A-insensitive NADH cytochrome c reductase and cytochrome c oxidase Absorbance plots of OD550 for 1 min need to follow... 

Seasonal Study of Mixed Function Oxidases.— A seasonal study of hepatic microsomal mfo components has been conducted in female R and S fish (submitted for publication). Components studied were cytochromes P-450 and 5, NADPH-cytochrome c reductase, NADPH-dichlorophenolindophenol reductase, NADH-cytochrome c reductase and NADH-cytochrome 5 reductase. All were monitored at 30°C by standard spectrophotometric methods following optimization procedures (8, 9 > 10, n, J 2). Microsomal and total hepatic protein (137 and liver weight to body weight ratios were also monitored. 

The activity of this segment of the MRC, NADH-cytochrome c reductase, is often difficult to measure due to the presence of contaminating activity, which may represent as high as 90% of the activity depending on the type of tissues/cells studied... 

Benzoate 1,2-dioxygenase was shown to catalyze the conversion of benzoate to l,2-dihydro-l,2-dihydroxybenzoic acid (DHB) in the presence of NADH and oxygen by Reiner et al.205, 206). Yamaguchi et al.61> have demonstrated that the enzyme system consists of two components (A and B),both of which are required for benzoate 1,2-dioxygenase activity. Component A shows NADH-cytochrome c reductase activity and component B appears to be dioxygenase, thus the following reaction scheme is suggested [Eq. (25)]. 

Small, I.S. Wray, J.L. (1980). NADH nitrate reductase and related NADH cytochrome c reductase species in barley. Phytochemistry 19, 387-94. 

NADH- cytochrome c reductase, EC 1.6.99.3 within mitochondria 50 mM NADH 0.5 mM N,N,N, N -tetramethyl-p-phenylenediamine oxidation [34]... 

Licochalcone A and C have been shown to possess activity in vitro against Gram-positive bacteria (Haraguchi et al., 1998). The mechanism of this effect is hypothesized to be inhibition of oxygen consumption and NADH oxidation in susceptible bacterial cells through inhibition of mitochondrial NADH-cytochrome c reductase. 

As stated above, SECM can be used to image the reactivity of surface features. A feedback detection scheme was used to observe the localized reaction of glucose oxidase and mitochondria-bound NADH-cytochrome c reductase (7). The spatial resolution of the imaging is high for enzymatic... 

Takamiya, S., Furushima, R. and Oya, H. (1984) Electron transfer complexes of Ascaris suum muscle mitochondria. I. Characterization of NADH cytochrome c reductase (complex I 111), with special reference to cytochrome localization. Mol. Biochem. Parasitol. 13 121-134. 

Rotenone-insensitive NADH-cytochrome c reductase Chap. 10... 

FI 2 NADH cytochrome c reductase in lipid peroxidation (prop.) Dicarboximides Iprodione, procymidone, vinclozolin Predominately used for Botrytis and related pathogens... 

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