Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Malates”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1992

Electrogenic malate uptake and improved growth energetics of the malolactic bacterium Leuconostoc oenos grown on glucose-malate mixtures.

Growth of the malolactic bacterium Leuconostoc oenos was improved with respect to both the specific growth rate and the biomass yield during the fermentation of glucose-malate mixtures as compared with those in media lacking malate. Such a finding indicates that the malolactic reaction contributed to the energy budget of the bacterium, suggesting that growth is energy limited in the absence of malate. An energetic yield (YATP) of 9.5 g of biomass.mol ATP-1 was found during growth on glucose with an ATP production by substrate-level phosphorylation of 1.2 mol of ATP.mol of glucose-1. During the period of mixed-substrate catabolism, an apparent YATP of 17.7 was observed, indicating a mixotrophy-associated ATP production of 2.2 mol of ATP.mol of glucose-1, or more correctly an energy gain of 0.28 mol of ATP.mol of malate-1, representing proton translocation flux from the cytoplasm to the exterior of 0.56 or 0.84 H+.mol of malate-1(depending on the H+/ATP stoichiometry). The growth-stimulating effect of malate was attributed to chemiosmotic transport mechanisms rather than proton consumption by the malolactic enzyme. Lactate efflux was by electroneutral lactate -/H+ symport having a constant stoichiometry, while malate uptake was predominantly by a malate -/H+ symport, though a low-affinity malate- uniport was also implicated. The measured electrical component (delta psi) of the proton motive force was altered, passing from -30 to -60 mV because of this translocation of dissociated organic acids when malolactic fermentation occurred.

Adenosine Triphosphate↗
PubMed1978

Malate dehydrogenase. Kinetic studies of substrate activation of supernatant enzyme by L-malate.

At pH 8.0 in 0.05 M Tris-acetate buffer at 25 degrees C, homogeneous supernatant malate dehydrogenase exhibits substrate activation by L-malate. The turnover number, Michaelis constant for L-malate, and Michaelis constant for NAD are: 0.46 X 10(4) min(-1), 0.036 mM, and 0.14 mM, respectively, for nonactivated enzyme and 1.1 X 10(4) min(-1), 0.2mM, and 0.047 mM for the same series of constants in activated enzyme. Nonactivating behavior is observed at concentrations between 0.02 and 0.15 mM L-malate and activating behavior is observed between 0.15 and 0.5 mM L-malate. L-Malate activation is compared with similar activation of mitochondrial malate dehydrogenase. While it is not possible to exclude unequivocally all mechanisms, the data seem to be consistent with the occurrence of a fundamentally ordered bi bi mechanism, possibly involving activation through the allosteric binding of L-malate. It is concluded that the data are consistent with a form of the "reciprocating compulsory order mechanism" in which nonactivated enzyme reflects catalysis by one subunit and activated catalysis expresses the coordinated activity of two subunits. The allosteric interaction and the "reciprocating mechanism/ are not mutually exclusive.

Animals↗
PubMed1975

Malate dehydrogenase, anticooperative NADH, and L-malate binding in ternary complexes with Supernatant pig heart enzyme.

Supernatant malate dehydrogenase from pig heart, a dimeric protein containing two very similar or identical subunits, shows negatively cooperative (anticooperative) interactions between NADH binding sites in the presence, but not in the absence, of 0.1 M L-malate. This behavior is observed consitently whether the technique used employs protein fluorescence quenching, NADH fluorescence enhancement, or ultrafiltration dialysis. Fluorescence titration shows that L-malate is also anticooperatively bound in the presence of saturating concentrations of NADH. The data are consistent with an "induced asymmetry" model in which conformational change accompanies the formation of the ternary complex. Two of the three chromatographically resolvable forms of the enzyme have been tested and found to have anticooperative behavior.

Animals↗
PubMed1992

Limited proteolysis of NADP-malate dehydrogenase from pea chloroplast by aminopeptidase K yields monomers. Evidence of proteolytic degradation of NADP-malate dehydrogenase during purification from pea.

NADP-malate dehydrogenase (L-malate: NADP oxidoreductase, EC 1.1.1.82) from leaves of Pisum sativum has been purified to homogeneity, as judged by polyacrylamide gel electrophoresis. In the crude leaf extract and in the absence of protease inhibitors in the isolation medium, the N-terminus of NADP-MDH was found to be highly susceptible to proteolysis. Evidence of proteolysis during purification includes observations of reduced subunit size on SDS-PAGE and reduced specific activity. Experiments were carried out to investigate the function of the N-terminal amino acid sequence extension of NADP-MDH. Limited proteolysis of highly active (600 units/mg protein) NADP-MDH using aminopeptidase K yielded catalytically active monomers of 34.7 kDa. The results support the conclusions that the N-terminal region is located at the surface of the protein, and that for maintenance of the native NADP-MDH dimer an N-terminal amino acid sequence is important.

Amino Acid Sequence↗
PubMed1976

Suppression of the mitochondrial oxidation of (-)-palmitylcarnitine by the malate-aspartate and alpha-glycerophosphate shuttles.

Palmitylcarnitine oxidation by isolated liver mitochondria has been used to investigate the interaction of fatty acid oxidation with malate, glutamate, succinate, and the malate-aspartate shuttle. Mitochondria preincubated with fluorocitrate were added to a medium containing 2mM ATP and ATPase. This system, characterized by a high energy change, allowed titration of respiration to any desired rate between States 4 and 3 (Chance, B., and Williams, G. R. (1956) Adv. Enzymol. Relat. Areas Mol. Biol. 17, 65-134). When respiration (reference, with palmitylcarnitine and malate as substrates) was set at 75% of State 3, the oxidation of palmitylcarnitine was limited by acetoacetate formation. The addition of malate or glutamate approximately doubled the rate of beta oxidation. Malate circumvented this limitation by citrate formation, but the effect of glutamate apparently was due to enhancement of the capacity for ketogenesis. The rate of beta oxidation was curtailed when malate and glutamate were both present. This curtailment was more pronounced when the malate-aspartate shuttle was fully reconstituted. Among the oxidizable substrates examined, succinate was most effective in inhibiting palmitylcarnitine oxidation. Mitochondrial NADH/NAD+ ratios were correlated positively with suppression of beta oxidation. The degree of suppression of beta oxidation by the malate-aspartate shuttle (NADH oxidation) or by succinate oxidation was dependent on the respiratory state. Both substrates extensively reduced mitochondrial NAD+ and markedly suppressed beta oxidation as respiration approached State 4. Calculations of the rates of flux of hydrogen equivalents through beta oxidation show that the suppression of beta oxidation by glutamate or by the malate-aspartate shuttle is accounted for by increased flux of reducing equivalents through mitochondrial malic dehydrogenase. This increased Flux is accompanied by an increase in the steady state NADH/NAD+ ratio and a marked decrease in the synthesis of citrate. The alpha-glycerophosphate shuttle was reconstituted with mitochondria isolated from rats treated with L-thyroxine. This shuttle was about equal to the reconstructed malate-aspartate shuttle in supression of palmitylcarnitine oxidation. This interaction could not be demonstrated in euthyroid animals owing to the low activity of the mitochondrial alpha-glycerol phosphate dehydrogenase. It is concluded that beta oxidation can be regulated by the NADH/NAD+ ratio. The observed stimulation of flux through malate dehydrogenase both by glutamate and by the malate-aspartate shuttle results in an increased steady state NADH/NAD+ ratio, and is linked to a stoichiometric outward transport of aspartate. We suggest, therefore, that some of the reducing pressure exerted by the malate-aspartate shuttle and by glutamate plus malate is provided through the energy-linked, electrogenic transport of aspartate out of the mitochondria. These results are discussed with respect to the mechanism of the genesis of ethanol-induced fatty liver.

Animals↗
PubMed1976

Repression of sporulation in Bacillus subtilis by L-malate.

L-Malate repressed sporulation in the wild-type strain of Bacillus subtilis. When 75 mM L-malate was added to the growth medium at the time of inoculation, the appearance of heat-resistant spores was delayed 6 to 8 h. The synthesis of extracellular serine protease, alkaline phosphatase, glucose dehydrogenase, and dipicolinic acid was similarly delayed. Sporulation was not repressed when malate was added to the culture at t4 or later. A mutant was selected for ability to sporulate in the presence of malate. This strain could also sporulate in the presence of glucose. The malate-resistant mutant grew poorly with malate as sole carbon source, although it possessed an intact citric acid cycle, and it showed increased levels of malic enzyme. This indicates a defect in the metabolism of malate in the mutant. A mutant lacking malate dehydrogenase activity was also able to sporulate in the presence of malate. A model for the regulation of sporulation by malate is presented and discussed. Citric acid cycle intermediates other than malate did not affect sporulation. In contrast to previous results, sporulation of certain citric acid cycle mutants could be greatly increased or completely restored by the addition of intermediates after the enzymatic block. The results indicate that the failure of citric acid cycle mutants to sporulate can be adequately explained by lack of energy and lack of glutamate.

Alcohol Oxidoreductases↗
PubMed1975

De novo synthesis and developmental control of the multiple gene-controlled malate dehydrogenase isozymes in maize scutella.

In maize, both soluble and mitochondrial malate dehydrogenases (L-malate:NAD oxidoreductase, EC 1.1.1.37)exist in multiple molecular forms (isozymes). Biochemical studies and genetic analysis showed that the maize malate dehydrogenase isozymes are not interconvertable conformational forms of a single gene product. Instead, they are determined by multiple genes which may reside on different chromosomes. Therefore, developmental expression of the various malate dehydrogenase isoqymes was studied. During early development of the sporophyte (dry kernel to 10 days of germination), the total malate dehydrogenase activity in scutella increases through the first 5 days, peaks about the 6th day and decreases gradually thereafter. Both soluble and mitochondrial malate dehydrogenase isozymes exhibit similar activity profiles; however, the total mitochondrial malate dehydro genase activity is only 60% of that in the cytosol. Density labeling experiments and atempts to detect the possible existence of "inactive malate dehydrogenase precursors" were performed. The results show that both soluble and mitochondrial malate dehydrogenase are synthesized in the scutella during germination and early growth of young maize seedlings. Accumulation of the maize malate dehydrogenase isozymes is probably controlled by synthesis as well as degradation instead of activation and inactivation of enzyme moieties. Correlation between the developmental pattern of the scutellar malate dehydrogenase isozymes and the physiological conditions of the young maize seedlings is discussed.

Centrifugation, Density Gradient↗
PubMed1975

Variations in the pathways of malate oxidation and phosphorylation in different species of Mycobacteria.

Mycobacterium tuberculosis H37Rv, the slow-growing human pathogenic strain of tubercle bacilli and Mycobacterium smegmatis and Mycobacterium phlei, the fast-growing saprophytes, have shown variations regarding the type of dehydrogenase that initiates malate oxidation in the respiratory chain. M. tuberculosis H37Rv is characterized by having a malate oxidase system (designated MALNAD pathway) in which malate oxidation is mediated by the NAD+-dependent malate dehydrogenase (EC 1.1.1.37) but not by FAD-dependent malate-vitamin K reductase. M. smegmatis possesses a different malate oxidase system (designated MALFAD pathway) in which malate oxidation is exclusively carried out by the FAD-dependent malate-vitamin K reductase because NAD+-dependent malate dehydrogenase is absent in this organism. M. phlei has a mixed system of malate oxidase (designated MALNAD+FAD pathways) in which both the NAD+-and FAD-dependent dehydrogenases take part. In all the three systems, the rest of the electron transport chain is common.

Alcohol Oxidoreductases↗
PubMed1975

Purification and properties of malate dehydrogenase from Pseudomonas testosteroni.

Nicotinamide adenine dinucleotide-linked malate dehydrogenase has been purified from Pseudomonas testosteroni (ATCC 11996). The purification represents over 450-fold increase in specific activity. The amino acid composition of the enzyme was determined and found to be quite different from the composition of the malate dehydrogenases from animal sources as well as from Escherichia coli. Despite this difference, however, the data show that the enzymatic properties of the purified enzyme are remarkably similar to those of other malate dehydrogenases that have been previously studied. The Pseudomonas enzyme has a molecular weight of 74,000 and consists of two subunits of identical size. In addition to L-malate, the enzyme slowly oxidizes other four-carbon dicarboylates having an alpha-hydroxyl group of S configuration such as meso- and (-) tartrate. Rate-determining steps, which differ from that of the reaction involving L-malate, are discussed for the reaction involving these alternative substrates. Oxidation of hydroxymalonate, a process previously undetected with other malate dehydrogenases, is demonstrated fluorometrically. Hydroxymalonate and D-malate strongly enhance the fluorescence of the reduced nicotinamide adenine dinucleotide bound to the enzyme. The enzyme is A-stereospecific with respect to the coenzyme. Malate dehydrogenase is present in a single form in the Pseudomonas. The susceptibility of the enzyme to activation or inhibition by its substrates-particularly the favoring of the oxidation of malate at elevated concentrations-strongly resembles the properties of the mitochondrial enzymes. The present study reveals that whereas profound variations in chemical composition have occurred between the prokaryotic and eukaryotic enzymes, the physical and catalytic properties of malate dehydrogenase, unlike lactate dehydrogenase, are well conserved during the evolutionary process.

Amino Acids↗
PubMed1992

Specific inhibition of Physarum polycephalum DNA-polymerase-alpha-primase by poly(L-malate) and related polyanions.

Poly(L-malate) is an unusual polyanion found in nuclei of plasmodia of Physarum polycephalum. We have investigated, by enzymatic and fluorimetric methods, whether poly(L-malate) and structurally related polyanions can interact with DNA-polymerase-alpha-primase complex and with histones of P. polycephalum. Poly(L-malate) is found to inhibit the activities of the DNA-polymerase-alpha-primase complex and to bind to histones. The mode of inhibition is competitive with regard to DNA in elongation and noncompetitive in the priming of DNA synthesis. Spermidine, spermine, and histones from P. polycephalum and from calf thymus bind to poly(L-malate) and antagonize the inhibition. The polyanions poly(vinyl sulfate), poly(acrylate), poly(L-malate), poly(D,L-malate), poly(L-aspartate), poly(L-glutamate) have been examined for their potency to inhibit the DNA polymerase. The degree of inhibition is found to depend on the distance between neighboring charges, given by the number of atoms (N) interspaced between them. Poly(L-malate) (N = 5) and poly(D,L-malate) (N = 5) are the most efficient inhibitors, followed by poly(L-aspartate) (N = 6), poly(acrylate) (N = 3), poly(L-glutamate) (N = 8), poly(vinyl sulfate) (N = 3). It is proposed that poly(L-malate) interacts with DNA-polymerase-alpha-primase of P. polycephalum. According to its physical and biochemical properties, poly(L-malate) may alternatively function as a molecular chaperone in nucleosome assembly in the S phase and as both an inhibitor and a stock-piling agent of DNA-polymerase-alpha-primase in the G2 phase and M phase of the plasmodial cell cycle.

Animals↗
PubMed1992

Crystal structure of Escherichia coli malate dehydrogenase. A complex of the apoenzyme and citrate at 1.87 A resolution.

The crystal structure of malate dehydrogenase from Escherichia coli has been determined with a resulting R-factor of 0.187 for X-ray data from 8.0 to 1.87 A. Molecular replacement, using the partially refined structure of porcine mitochondrial malate dehydrogenase as a probe, provided initial phases. The structure of this prokaryotic enzyme is closely homologous with the mitochondrial enzyme but somewhat less similar to cytosolic malate dehydrogenase from eukaryotes. However, all three enzymes are dimeric and form the subunit-subunit interface through similar surface regions. A citrate ion, found in the active site, helps define the residues involved in substrate binding and catalysis. Two arginine residues, R81 and R153, interacting with the citrate are believed to confer substrate specificity. The hydroxyl of the citrate is hydrogen-bonded to a histidine, H177, and similar interactions could be assigned to a bound malate or oxaloacetate. Histidine 177 is also hydrogen-bonded to an aspartate, D150, to form a classic His.Asp pair. Studies of the active site cavity indicate that the bound citrate would occupy part of the site needed for the coenzyme. In a model building study, the cofactor, NAD, was placed into the coenzyme site which exists when the citrate was converted to malate and crystallographic water molecules removed. This hypothetical model of a ternary complex was energy minimized for comparison with the structure of the binary complex of porcine cytosolic malate dehydrogenase. Many residues involved in cofactor binding in the minimized E. coli malate dehydrogenase structure are homologous to coenzyme binding residues in cytosolic malate dehydrogenase. In the energy minimized structure of the ternary complex, the C-4 atom of NAD is in van der Waals' contact with the C-3 atom of the malate. A catalytic cycle involves hydride transfer between these two atoms.

Amino Acid Sequence↗
PubMed1992

Uptake and metabolism of malate in neurons and astrocytes in primary cultures.

Uptake and oxidative metabolism of [14C]malate as well as its incorporation into aspartate, glutamate, glutamine, and GABA were studied in cultured cerebral cortical neurons (GABAergic), cerebellar granule neurons (glutamatergic), and cerebral cortical astrocytes. All cell types exhibited high affinity uptake of malate (Km 10-85 microM) with slightly higher Vmax values in neurons (0.1-0.2 nmol x min-1 x mg-1) than in astrocytes (0.06 nmol x min-1 x mg-1). Malate was oxidatively metabolized in all three cell types with nominal rates of 14CO2 production of 2-15 pmol x min-1 x mg-1. The oxidation of malate was only slightly inhibited by 5 mM aminooxyacetic acid (AOAA). In granule cell preparations [14C]malate was incorporated into aspartate and glutamate and, to a much less extent, into glutamine. This incorporation was blocked by 5 mM AOAA. Astrocytes exhibited slightly higher incorporation rates into aspartate and glutamate, but in these cells glutamine was labelled to a considerable extent. AOAA (5 mM) inhibited the incorporation by 60-70%. In cultures of cerebral cortical neurons, very low levels of radioactivity derived from [14C]malate were found in aspartate and glutamate, and GABA was not labelled at all. Glutamine had the same specific activity as glutamate, indicating that the low rates of incorporation of radioactivity into amino acids in this preparation is likely to exclusively represent metabolism of malate in the small population of astrocytes (5% of total cell number), contaminating the neuronal cultures. The findings suggest that exogenous malate to a quantitatively limited extent may serve as a precursor for transmitter glutamate in glutamatergic neurons.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Identification of an essential histidine residue at the active site of the tonoplast malate carrier in Catharanthus roseus cells.

The involvement of a histidyl residue in the binding or translocation step was investigated in the malate carrier at the tonoplast of Catharanthus roseus cells. The transport rate was strongly stimulated when the pH of the incubation medium was decreased from pH 7.0 to 5.0. The histidine-specific reagent diethylpyrocarbonate (DEPC) efficiently inhibited the activity of the malate carrier. Inhibition developed rapidly and was completed after 5 min at a concentration of 2 mM DEPC. The original substrate, malate, partially protected the carrier from inactivation by DEPC. Other organic acids (citrate, quinate) which are known to affect the malate transport of isolated vacuoles or tonoplast vesicles also showed protective properties. Inhibition of malate transport on tonoplast vesicles can also be achieved by photooxidation in the presence of the dye Rose Bengal. Malate also proved to protect against inactivation. The results strongly support the notion that a histidyl residue(s) is involved either in the binding or translocation of malate and that the protonation of the histidyl residue is essential to provide a high rate of malate transport.

Biological Transport↗
PubMed1976

Energization of mitochondrial inner membranes caused by L-malate.

It was found that 0.06 mug antimycin A/mg mitochondrial protein, an amount sufficient to inhibit electron transfer between cytochromes b and c1 completely, fully reversed the oxidation of cytochrome a caused by L-malate in anaerobic mitochondria. The effect of L-malate on cytochrome a was insensitive to oligomycin, but all the uncouplers and detergents tested reversed the oxidation of cytochrome a caused by L-malate in anaerobic mitochondria. It was also found that addition of L-malate to anaerobic mitochondria, like addition of ATP, decreased the fluorescence of 1-anilinonaphthalene-8-sulphonate, and that subsequent addition of uncouplers reversed this effect. The effect of L-malate on the fluorescence of the dye was insensitive to oligomycin. The present findings suggest that addition of L-malate may cause energization of the mitochondrial inner membranes and that the oxidation of cytochrome a caused by L-malate in anaerobic mitochondria may result from an L-malate-induced, energy-linked reversal of electron transfer in site II.

Adenosine Triphosphate↗
PubMed1992

Purification and properties of Plasmodium falciparum malate dehydrogenase.

Asexual intraerythrocytic Plasmodium falciparum were shown to have a single isoenzyme of malate dehydrogenase. This malate dehydrogenase was purified to apparent homogeneity using a three-step purification protocol. The parasite malate dehydrogenase had an apparent subunit molecular weight of 32 kDa, a pH optimum of 7.0 for the reduction of oxaloacetate, and a sharp thermal transition between 40 degrees C and 45 degrees C. These characteristics distinguish P. falciparum malate dehydrogenase from both the cytoplasmic and mitochondrial malate dehydrogenase isoenzymes of humans. In addition, the resistance of the parasite malate dehydrogenase to substrate inhibition by oxaloacetate suggests that it is the cytoplasmic malate dehydrogenase isoenzyme. The apparent absence of mitochondrial malate dehydrogenase from asexual intraerythrocytic P. falciparum contributes to evidence indicating that the mitochondrion is undeveloped at this stage of the parasite's life cycle.

Animals↗
PubMed1978

Studies on the mechanism of the malate dehydrogenase reaction.

The stereospecificity of the chicken heart mitochondrial malate dehydrogenase as well as the ability of this enzyme to form various abortive complexes has been further investigated. The enzyme was found to be specific for the A-hydrogen of NADH. Complex formation of the enzyme with oxalacetate and oxidized coenzymes is pH-dependent and is promoted at alkaline pH values. The enol form of oxalacetate appears to be the species that participates in the formation of the complexes. The binding of L-malate, D-malate, or hydroxymalonate to the enzyme. NADH complex is also pH-dependent, and involves a group on the enzyme with a pK of 7.5. The binding of L-malate is promoted at alkaline pH values, whereas the binding of D-malate and hydroxymalonate is favored at acidic pH values. These results indicate that L-malate and enol-oxalacetate preferentially or exclusively bind to the nonprotonated form of the enzyme, whereas keto-oxalactate, hydroxymalonate, and D-malate only bind to the protonated form of the enzyme. Based on this conclusion, a detailed chemical mechanism for the malate dehydrogenase reaction has been postulated and a schematic illustration of the transition state of the enzyme is presented.

Animals↗
PubMed1975

Malate dehydrogenase, circular dichroism difference spectra of porcine heart mitochondrial and supernatant enzymes, binary enzyme-coenzyme, and ternary enzyme-coenzyme-substrate analog complexes.

Circular dichroism spectra and circular dichroism difference spectra, generated when porcine heart mitochondrial and supernatant malate dehydrogenase bind coenzymes or when enzyme dihydroincotinamide nucleotide binary complexes bind substrate analogs, are presented. No significant changes are observed in protein chromophores in the 200- to 240-nm spectral range indicating that there is apparently little or no perturbation of the alpha helix or peptide backbone when binary or ternary complexes are formed. Quite different spectral perturbances occur in the two enzymes with reduced coenzyme binding as well as with substrate-analog binding by enzyme-reduced coenzyme binding. Comparison of spectral perturbations in both enzymes with oxidized or reduced coenzyme binding suggests that the dihydronicotinamide moiety of the coenzyme interacts with or perturbs indirectly the environment of aromatic amino acid residues. Reduced coenzyme binding apparently perturbs tyrosine residues in both mitochondrial malate dehydrogenase and lactic dehydrogenase. Reduced coenzyme binding perturbs tyrosine and tryptophan residues in supernatant malate dehydrogenase. The number of reduced coenzyme binding sites was determined to be two per 70,000 daltons in the mitochondrial enzyme, and the reduced coenzyme dissociation constants, determined through the change in ellipticity at 260 nm, with dihydronicotinamide adenine dinucleotide binding, were found to be good agreement with published values (Holbrook, J. J., and Wolfe, R. G. (1972) Biochemistry 11, 2499-2502) obtained through fluorescence-binding studies and indicate no apparent extra coenzyme binding sites. When D-malate forms a ternary complex with malate dehydrogenase-reduced coenzyme complexes, perturbation of both adenine and dihydronicotinamide chromophores is evident. L-Malate binding, however, apparently produces only a perturbation of the adenine chromophore in such complexes. Since the coenzyme has been found to bind in an open conformation on the surface of the enzyme and the substrate analogs bind at or very near the dihydronicotinamide moiety binding site, protein conformational changes are implicated during ternary complex formation with D-malate which can effect the adenine chromophore at some distance from the substrate binding site.

Animals↗