The involvement of nicotinamide adenine nucleotides (NAD(+), NADH) in the regulation of glycolysis in Lactococcus lactis was investigated by using (13)C and (31)P NMR to monitor in vivo the kinetics of the pools of NAD(+), NADH, ATP, inorganic phosphate (P(i)), glycolytic intermediates, and end products derived from a pulse of glucose. Nicotinic acid specifically labeled on carbon 5 was synthes...

UNLABELLED NADH:quinone oxidoreductase (complex I) is a bioenergetic enzyme that transfers electrons from NADH to quinone, conserving the energy of this reaction by contributing to the proton motive force. While the importance of NADH oxidation to mitochondrial aerobic respiration is well documented, the contribution of complex I to bacterial electron transport chains has been tested in only a ...

Recent experiments show that exogenous NADH increases the O(2) consumption and uptake of inorganic ions into isolated corn (Zea mays L. Pioneer Hybrid 3320) root protoplasts (Lin 1982, Proc Natl Acad Sci USA 79: 3773-3776). A mild treatment of protoplasts with trypsin released most of the NADH oxidation system from the plasmalemma (Lin 1982 Plant Physiol 70: 326-328). Further studies on this sy...

NADH:quinone oxidoreductase (complex I) couples NADH oxidation and quinone reduction to proton translocation across an energy-transducing membrane. All complexes I contain a flavin to oxidize NADH, seven iron-sulfur clusters to transfer electrons from the flavin to quinone and an eighth cluster (N1a) on the opposite side of the flavin. The role of cluster N1a is unknown, but Escherichia coli co...

NADH kinase (NADHK; ATP:NADH 2'-phosphotransferase; EC 2.7.1.86), an enzyme that preferentially utilizes NADH as the diphosphonicotinamide nucleotide donor, has been identified for the first time in plants. Low activity (0.4 nmol of NADPH produced/min per mg of protein) was observed in clarified protein extracts from Arabidopsis thaliana (thale cress) cell suspension cultures. However, unlike a...

Cytochrome b5 of rat liver microsomes is reduced by a-NADH ; the extent of reduction is equal to that obtained with P-NADH. With both nucleotides, the rates of reduction of cytochrome b5 are very fast ; alternatively, rates of reduction of cytochrome c and dichloroindophenol have been measured. The rates observed with a+NADH are about 10% of the rates observed with P-NADH. Conditions have been ...

Cytochrome b5 of rat liver microsomes is reduced by a-NADH ; the extent of reduction is equal to that obtained with P-NADH. With both nucleotides, the rates of reduction of cytochrome b5 are very fast ; alternatively, rates of reduction of cytochrome c and dichloroindophenol have been measured. The rates observed with a+NADH are about 10% of the rates observed with P-NADH. Conditions have been ...

Ischemic preconditioning (IPC) strongly protects against ischemia-reperfusion injury; however, its effect on subsequent myocardial oxygenation is unknown. Therefore, we determine in an in vivo mouse model of regional ischemia and reperfusion (I/R) if IPC attenuates postischemic myocardial hyperoxygenation and decreases formation of reactive oxygen/nitrogen species (ROS/RNS), with preservation o...