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Progress in Clinical and Biological... 1990
Review
Topics: Animals; Chromosome Mapping; Chromosomes, Human, Pair 11; Humans; Isoenzymes; L-Lactate Dehydrogenase; Male; Spermatogenesis
PubMed: 2203052
DOI: No ID Found -
Journal of Bacteriology Feb 1978Rhodopseudomonas sphaeroides has a pyridine nucleotide-independent L-lactate dehydrogenase associated with the membrane fraction of cells grown either aerobically or...
Rhodopseudomonas sphaeroides has a pyridine nucleotide-independent L-lactate dehydrogenase associated with the membrane fraction of cells grown either aerobically or phototrophically. The dehydrogenase is present in cells grown on a variety of carbon sources, but at levels less than 20% of that found in cells grown with DL-lactate. The dehydrogenase has been purified 45-fold from membranes of strain L-57, a non-photosynthetic mutant, by steps involving solubilization with lauryl dimethylamine oxide and three anion-exchange chromatography steps. The purified enzyme was specific for the L-isomer of lactate. The Km of the purified enzyme for L-lactate is 1.4 mM, whereas that of the membrane-associated enzyme is 0.5 mM. The enzyme activity was inhibited competitively by D-lactate and non-competitively by oxalate and oxamate. Quinacrine, a flavin analog, also inhibited the activity. The inducible enzyme may serve as a marker of membrane protein in studies of membrane development.
Topics: Cell Membrane; Chromatography, DEAE-Cellulose; Chromatography, Ion Exchange; Kinetics; L-Lactate Dehydrogenase; Oxalates; Oxamic Acid; Quinacrine; Rhodobacter sphaeroides; Substrate Specificity
PubMed: 304854
DOI: 10.1128/jb.133.2.593-600.1978 -
Physiological Research 1997Lactate dehydrogenase (LDH) activity and its isoenzymatic fractions were measured in bone marrow blood and in peripheral venous blood from 16 haematologically normal...
Lactate dehydrogenase (LDH) activity and its isoenzymatic fractions were measured in bone marrow blood and in peripheral venous blood from 16 haematologically normal subjects. Total LDH activity was significantly higher in marrow than in venous blood (428.8 +/- 98.4 vs 260.1 +/- 40.2 mU/l, p < 0.0001). The same was true for the absolute values of its isoenzymatic fractions. The percentage fractions LDH 1 and LDH 5 were similar in the two regions, while LDH 3 and LDH 4 were higher in medullary blood (p < 0.05) and LDH 2 was higher in peripheral blood (p < 0.05). The Spearman test showed a limited correlation between marrow and peripheral total LDH activity values (p < 0.05). This seems to be at least in part sustained by the highly significant correlations existing in LDH 3 and LDH 4 values, reported to be pre-eminent isoforms in maturing haematopoietic cells (p < 0.005 and p < 0.001, respectively). These findings could be attributed to an apoptotic regulation of marrow cell production.
Topics: Adult; Bone Marrow; Female; Humans; Isoenzymes; L-Lactate Dehydrogenase; Male; Middle Aged; Reference Values
PubMed: 9730049
DOI: No ID Found -
Journal of Chromatography. B,... Sep 1996Lactate dehydrogenase (LDH), an ubiquitous enzyme among vertebrates, invertebrates, plants and microbes was discovered in the early period of enzymology. The enzyme has... (Review)
Review
Lactate dehydrogenase (LDH), an ubiquitous enzyme among vertebrates, invertebrates, plants and microbes was discovered in the early period of enzymology. The enzyme has been dissolved in several distinguishable molecular forms. In mammals, three types of subunits encoded by the genes Ldh-A, Ldh-B and Ldh-C give rise to a selected number of tetrameric isoenzymes. LDH-A4, LDH-B4 and the mixed hybrid forms of the A- and B-subunits are present in many tissues but with certain distribution patterns. LDH-C4 is confined in mammals to testes and sperm. Numerous techniques have been employed to purify, characterize and separate the different forms of the enzyme. This report deals with the main protocols and procedures of purification of LDH and its isoenzymes including chromatographic and electrophoretic methods, partitioning in aqueous two-phase systems and precipitation approaches. In particular, affinity separation techniques based on natural and pseudo-biospecific ligands are described in detail. In addition, basic physico-chemical and kinetic properties of the enzyme from different sources are summarized in a second part, the clinical significance of the determination of LDH in diverse body fluids in respect to the total activity and the isoenzyme distribution in different organs is discussed.
Topics: Animals; Chromatography, Liquid; Coloring Agents; Humans; L-Lactate Dehydrogenase; Ligands
PubMed: 8906464
DOI: 10.1016/0378-4347(96)00133-8 -
Molecular Biology and Evolution Sep 2022We unveil the intimate relationship between protein dynamics and allostery by following the trajectories of model proteins in their conformational and sequence spaces....
Protein Conformational Space at the Edge of Allostery: Turning a Nonallosteric Malate Dehydrogenase into an "Allosterized" Enzyme Using Evolution-Guided Punctual Mutations.
We unveil the intimate relationship between protein dynamics and allostery by following the trajectories of model proteins in their conformational and sequence spaces. Starting from a nonallosteric hyperthermophilic malate dehydrogenase, we have tracked the role of protein dynamics in the evolution of the allosteric capacity. Based on a large phylogenetic analysis of the malate (MalDH) and lactate dehydrogenase (LDH) superfamily, we identified two amino acid positions that could have had a major role for the emergence of allostery in LDHs, which we targeted for investigation by site-directed mutagenesis. Wild-type MalDH and the single and double mutants were tested with respect to their substrate recognition profiles. The double mutant displayed a sigmoid-shaped profile typical of homotropic activation in LDH. By using molecular dynamics simulations, we showed that the mutations induce a drastic change in the protein sampling of its conformational landscape, making transiently T-like (inactive) conformers, typical of allosteric LDHs, accessible. Our data fit well with the seminal key concept linking protein dynamics and evolvability. We showed that the selection of a new phenotype can be achieved by a few key dynamics-enhancing mutations causing the enrichment of low-populated conformational substates.
Topics: Allosteric Regulation; Amino Acids; L-Lactate Dehydrogenase; Malate Dehydrogenase; Malates; Mutation; Phylogeny
PubMed: 36056899
DOI: 10.1093/molbev/msac186 -
JAMA Oct 1968
Topics: Electrophoresis; Isoenzymes; L-Lactate Dehydrogenase; Methods
PubMed: 5695621
DOI: 10.1001/jama.1968.03150020094035 -
Molecular Biology and Evolution Oct 2023Lactate dehydrogenase (LDH, EC.1.1.127) is an important enzyme engaged in the anaerobic metabolism of cells, catalyzing the conversion of pyruvate to lactate and NADH to...
Lactate dehydrogenase (LDH, EC.1.1.127) is an important enzyme engaged in the anaerobic metabolism of cells, catalyzing the conversion of pyruvate to lactate and NADH to NAD+. LDH is a relevant enzyme to investigate structure-function relationships. The present work provides the missing link in our understanding of the evolution of LDHs. This allows to explain (i) the various evolutionary origins of LDHs in eukaryotic cells and their further diversification and (ii) subtle phenotypic modifications with respect to their regulation capacity. We identified a group of cyanobacterial LDHs displaying eukaryotic-like LDH sequence features. The biochemical and structural characterization of Cyanobacterium aponinum LDH, taken as representative, unexpectedly revealed that it displays homotropic and heterotropic activation, typical of an allosteric enzyme, whereas it harbors a long N-terminal extension, a structural feature considered responsible for the lack of allosteric capacity in eukaryotic LDHs. Its crystallographic structure was solved in 2 different configurations typical of the R-active and T-inactive states encountered in allosteric LDHs. Structural comparisons coupled with our evolutionary analyses helped to identify 2 amino acid positions that could have had a major role in the attenuation and extinction of the allosteric activation in eukaryotic LDHs rather than the presence of the N-terminal extension. We tested this hypothesis by site-directed mutagenesis. The resulting C. aponinum LDH mutants displayed reduced allosteric capacity mimicking those encountered in plants and human LDHs. This study provides a new evolutionary scenario of LDHs that unifies descriptions of regulatory properties with structural and mutational patterns of these important enzymes.
Topics: Humans; Lactate Dehydrogenases; L-Lactate Dehydrogenase
PubMed: 37797308
DOI: 10.1093/molbev/msad223 -
Comparative Biochemistry and... Sep 1975
Topics: Adaptation, Physiological; Animals; Fishes; Isoenzymes; Kinetics; L-Lactate Dehydrogenase; Mathematics; Pressure; Seawater; Species Specificity; Temperature; Thermodynamics
PubMed: 1183174
DOI: 10.1016/0305-0491(75)90110-8 -
The Journal of Biological Chemistry Jun 1969
Topics: Amino Acids; Animals; Binding Sites; Catalysis; Chromatography, Gel; Chromatography, Ion Exchange; Crustacea; Dialysis; Fluorescence; Isoenzymes; L-Lactate Dehydrogenase; Molecular Weight; Muscles; NAD; Nicotinic Acids; Pyridines; Tail; Ultracentrifugation
PubMed: 4306287
DOI: No ID Found -
Biochimica Et Biophysica Acta Dec 1983Lactate dehydrogenase (D-lactate:NAD+ oxidoreductase, EC 1.1.1.28) from the horseshoe crab, Limulus polyphemus, a dimeric enzyme stereospecific for D-lactate, has been... (Comparative Study)
Comparative Study
Lactate dehydrogenase (D-lactate:NAD+ oxidoreductase, EC 1.1.1.28) from the horseshoe crab, Limulus polyphemus, a dimeric enzyme stereospecific for D-lactate, has been purified by affinity chromatography. Maleyl tryptic peptides containing arginine residues isolated from the Limulus enzyme have been characterized and sequenced. The small peptides obtained from similarly treated L-lactate-specific enzyme homologs define major portions of the substrate and coenzyme binding regions and are virtually identical among L-lactate-specific enzymes. Although the six small peptides and free arginine isolated from the Limulus enzyme indicate that the small number of arginine tryptic peptides are located in a few discrete consecutive clusters similarly to the L-lactate dehydrogenases, the peptides nevertheless show no obvious sequence homology to the corresponding peptides from L-lactate dehydrogenases. These results indicate that this lactate dehydrogenase of altered substrate specificity either evolved with major rearrangements of the active site if it evolved from an L-lactate dehydrogenase, or that D-lactate dehydrogenases have evolved from a different protein. The results contradict proposed models which suggest that minor changes in the spatial orientation of pyruvate resulting from minimal rearrangement of the active site could accommodate the change in substrate specificity.
Topics: Amino Acid Sequence; Animals; Binding Sites; Biological Evolution; Horseshoe Crabs; L-Lactate Dehydrogenase; Peptide Fragments; Stereoisomerism; Structure-Activity Relationship; Substrate Specificity
PubMed: 6652095
DOI: 10.1016/0167-4838(83)90247-9