L-Malate dehydrogenase

Mitochondrial L-malate dehydrogenase (bovine heart muscle)1501... 

Fig. 7. Enzyme-coupled assay in which the hydrolase-catalyzed reaction releases acetic acid. The latter is converted by acetyl-CoA synthetase (ACS) into acetyl-CoA in the presence of (ATP) and coenzyme A (CoA). Citrate synthase (CS) catalyzes the reaction between acetyl-CoA and oxaloacetate to give citrate. The oxaloacetate required for this reaction is formed from L-malate and NAD in the presence of L-malate dehydrogenase (l-MDH). Initial rates of acetic acid formation can thus be determined by the increase in adsorption at 340 nm due to the increase in NADH concentration. Use of optically pure (Ry- or (5)-acetates allows the determination of the apparent enantioselectivity i app i81)-...

Determination of the absolute configurations of the 3,6-dideoxy-hexoses involved their degradation, according to Scheme 2, to malic acid, and identification of the latter acid with L-malate dehydrogenase.56 The anomeric configuration in 9—12 was assumed to be the same... 

Oxidation of Malate to Oxaloacetate In the last reaction of the citric acid cycle, NAD-linked L-malate dehydrogenase catalyzes the oxidation of L-malate to oxaloacetate ... 

L-Malate dehydrogenase catalyzes the reversible oxidation of malate to ox-aloacetate, using NAD+ as a coenzyme (equation 16.6). 

Katrlik et al. [63] L-Malate, l-lactate Wines L-Malate dehydrogenase or l-lactate dehydrogenase and diaphorase/covered by a dialysis membrane NAD+-modified graphite-2-hexadecanone composite electrode Hexacyanoferrate(III)... 

Gajovic et al. [64] L-malate Fruits, fruit juices, ciders and wines NAD(P)+-dependent L-malate dehydrogenase oxaloacetate decarboxylating with salicylate hydroxylase (SHL)/ in gelatine membrane sandwiched between a dialysis membrane and a PET membrane Clark-electrode ... 

Sulfite modified enzyme electrode. (2) L-Lactate/L-malate/ sulfite multibiosensor L-lactate dehydrogenase/L-malate dehydrogenase/ sulfite oxidase surface-modified enzyme electrodes/enzymes were deposited on the composite electrodes and covered with a dialysis membrane ... 

Esti et al. [8] L-Lactate L-Malate Micro-malolactic fermentation in red wine Lactate oxidase/in a nylon membrane with glutaraldehyde or NAD(P)+-dependent l-malate dehydrogenase oxaloacetate decarboxylating/ immobilised in an aminopropyl glass beads reactor Platinum electrode/ +650mV vs. Ag/AgCl Phenazine methosulfate (for malate sensor)... 

Various Systems. 3.3.1. Water (l)-Malate Dehydrogenase (Hm MalDH) (2)—NaCl (3). For water (1)—Hm MalDH (2)—NaCl (3), experimental data for both F and OSVC are available. 3,44 -pbe partial molar volumes of the components of the protein-free mixed solvent (Vi and V3) were calculated from the densities of the water—NaCl... 

Configurational analysis of the [ H. HJcitrate involved conversion to [ H, H]malate by the sequential use of citrate lyase and L-malate dehydrogenase (197). 

Figure 3.1 Metabolic origin of plastid carbon source and enzyme cofactors required for de novo fatty acid synthesis, (a) Glycolytic enzymes (b) pyruvate kinasec (EC 2.7.1.40) (c) pyruvate kinasep (EC 2.7.1.40) (d) phosphoenolpyruvate (PEP) carboxylase (EC 4.1.1.31) (e) L-malate dehydrogenase (EC 1.1.1.37) (f) malic enzyme (EC 1.1.1.40) (g) pyruvate dehydrogenase (EC 1.2.4.1, EC 2.3.1.12, EC 1.8.1.4).

Increasing the amount of enzyme attached to the surface will increase the amount of electrochemically detectable cofactor (e.g., NADH, H2O2) produced in the enzymatic reaction, up to a point. It has been shown for at least one system that the optimum maximum concentration of enzyme on the surface can clearly be reached [27]. In this work two enzymes, NADP -dependent L-malate dehydrogenase and p-hydroxybenzoate hydroxylase, were immobilized on a Clark electrode. The resulting bienzyme sensor behaved as if a single enzyme with a selectivity for L-malate was immobilized, and the optimal surface concentration for both enzymes was found to be approximately 5 U/cm. Furthermore, in order to fabricate a microelectrode with the fast time response necessary to measure neu-... 

We have been principally occupied with that part of the question that deals with the onset of the process, i.e., the initiation and execution of fermentative derepression. To answer the question regarding transcriptional products we have used two approaches (1) determination whether a p mutant lacking mtDNA (p or DNA ) is still capable of derepression this approach is limited to the potentially derepressible entities still present in such a mutant such as cytochrome c or L-malate dehydrogenase (2) the use of EtdBr as a specific inhibitor for transcription this approach is somewhat clouded by reports that this agent, although specific for mitochondrial processes, may inhibit translation as well as transcription. Fortunately, both types of experiments give the same answer there is no evidence for the participation of mitochondrial transcripts in the initiation or execution of the fermentative phase of derepression. The same answer also applies to products of mitochondrial translation which we have assessed by the use of CAP as a specific inhibitor. 

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