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PubMed1983

Structure and function of L-lactate dehydrogenases from thermophilic and mesophilic bacteria. II) The primary structure of thermophilic lactate dehydrogenase from Bacillus stearothermophilus. Cyanogen bromide fragments and partial sequence.

The polypeptide chain of thermophilic lactate dehydrogenase from Bacillus stearothermophilus was split with cyanogen bromide. The 6 cyanogen bromide fragments were then separated and isolated by gel filtration (Bio-Gel P 10, Sephadex G-75) and ionic exchange chromatography (Biorex 70), respectively. Peptide fractionation was performed in 50% formic acid. Fragment yield varied between 30 and 75%. About 75% of the amino-acid sequence was determined by the automatic N-terminal sequence analysis (amino-acid sequenator) of the cyanogen bromide fragments (41-57 cycles degraded) and N-terminal region of lactate dehydrogenase (74 cycles degraded). Typical structure differences between thermophilic and mesophilic lactate dehydrogenases are already indicated by the comparison of the amino-acid composition of the thermophilic enzyme from B. stearothermophilus with the mesophilic from bacilli and higher organisms. Comparison of the N-terminal sequence reveals that sequence homology is higher (83-98%) between the thermophilic lactate dehydrogenases from B. stearothermophilus, B. caldotenax and B. caldolyticus than between the mesophilic lactate dehydrogenases of bacilli among each other or between thermophilic and mesophilic lactate dehydrogenases (about 60%). High temperature would appear to limit variation in structure.

Amino Acid Sequence↗
PubMed1993

Sequence analysis of teleost retina-specific lactate dehydrogenase C: evolutionary implications for the vertebrate lactate dehydrogenase gene family.

At least two gene duplication events have led to the three lactate dehydrogenase (LDH; EC 1.1.1.27) isozymes (LDH-A, LDH-B, and LDH-C) of chordates. The prevailing model for the evolution of the LDH loci involves duplication of a primordial LDH locus near the origin of vertebrates, giving rise to Ldh-A and Ldh-B. A third locus, designated Ldh-C, is expressed in the spermatocytes of mammals and a single family of birds and in the eye or liver tissues of teleost fishes. Ldh-C might have arisen independently in these taxa as duplications of either Ldh-A or Ldh-B. Several authors have challenged this traditional hypothesis on the basis of amino acid sequence and immunological similarity of the three LDH isozymes. They suggest that the primordial LDH gene was duplicated to form Ldh-C and a locus that later gave rise to Ldh-A and Ldh-B. We have differentiated between these hypotheses by determining the cDNA sequence of the retina-specific LDH-C from a teleost, Fundulus heteroclitus. On the basis of amino acid sequence similarity, we conclude that the LDH-C isozymes in fish and mammals are not orthologous but derive from independent gene duplications. Furthermore, our phylogenetic analyses support previous hypotheses that teleost Ldh-C is derived from a duplication of the Ldh-B locus.

Amino Acid Sequence↗
PubMed1979

Isoenzymes of hexokinase, 6-phosphogluconate dehydrogenase, phosphoglucomutase and lactate dehydrogenase in uterine cancer.

Electrophoresis of cytosol prepared from normal and malignant tissue samples of uterine cervix and endometrium revealed interesting differences which may be relevant to the characteristic alterations in glucose metabolism associated with tumour development. Hexokinase II was detected in 30% of the cancer material from both sources, but in none of the samples of normal cervix. A duplet band of 6-phosphogluconate dehydrognease was seen in the majority of the cancer samples but in no sample of normal cervix; it appeared to be partly due to ageing of the sample, and is not phenotypically related to the malignant process. Analysis of genetic variance for phosphoglucomutase at the PGM1 locus revealed a highly significant excess of the PGM1-1 phenotype in patients with cancer of the endometrium, which may reflect susceptibility to endometrial cancer in patients with this phenotype. At the PGM2 locus, samples of malignant cervix were deficient in "Band f" compared with normal cervix samples, all of which showed this band. Conversely, gene products of the PGM3 locus were found in most samples of malignant cervix and a small minority of normal cervix samples. Compared with the isomorphic distribution of lactate dehydrogenase enzymes in normal uterine tissue, cancers showed a shift towards either a more anodal or a more cathodal pattern. The former may be associated with tumours enjoying a good oxygen supply, and the latter with tumours which, because of their depth or poor blood supply have to function under less aerobic conditions.

Electrophoresis, Polyacrylamide Gel↗
PubMed1983

Structure and function of L-lactate dehydrogenases from thermophilic and mesophilic bacteria. III) The primary structure of thermophilic lactate dehydrogenase from Bacillus stearothermophilus. Hydroxylamine-, o-iodosobenzoic acid- and tryptic-fragments. The complete amino-acid sequence.

Based on the partial sequence of the cyanogen bromide fragments [Tratschin, J.D., Wirz, B., Frank, G. and Zuber, H. (1983) Hoppe-Seyler's Z. Physiol. Chem. 364, 879-892], the amino-acid sequence of thermophilic lactate dehydrogenase from B. stearothermophilus was completed by the preparation and sequencing (sequenator, carboxypeptidase A and Y) of further overlapping fragments. Suitable peptide fragments were obtained by lactate dehydrogenase cleavage with hydroxylamine, o-iodosobenzoic acid and trypsin. The polypeptide chain of thermophilic lactate dehydrogenase from B. stearothermophilus consists of 317 amino-acid residues. While sequence homology with mesophilic lactate dehydrogenase of higher organisms reaches 35%, it is substantially higher with this mesophilic enzyme of bacillae (greater than 60%, B. megaterium, B. subtilis). The secondary structure elements and amino-acid residues of the active site of thermophilic lactate dehydrogenase deducted from primary structure data were compared with those from the mesophilic enzyme, the same was done for the internal sequence homology at the nucleotide-binding units. A comparative structure analysis (matrix system) based on the primary structure data of thermophilic enzyme should provide insight into the characteristic structure differences between thermophilic and mesophilic lactate dehydrogenase.

Amino Acid Sequence↗
PubMed1977

[Action of pharmacological effectors on hematocrit and lactate dehydrogenase activity changes in experimental ischemic shock].

The experimental ischemic shock induced by removing tourniquets in rats, were studied. Durin 164 hours, the variations of the values of hematocrit and of muscle and plasma dehydrogenase lactate activity were followed up; the modifications of these variations after pharmacological high doses of dexamethasone phosphate, hydrocortisone hemisuccinate and aprotinine administered intravenously, were evaluated. The best action was noted after dexamethasone phosphate treatment.

Animals↗
PubMed1984

Rapid loss of lactate dehydrogenase isoenzyme activity in serum by cold-induced formation of immunoglobulin G-lactate dehydrogenase complex.

Lactate dehydrogenase (LD; EC 1.1.1.27) activity in serum from a patient recovering from a myocardial infarction was extremely unstable when stored at 0 degree C. The activity of each LD isoenzyme except LD-1 decreased by at least 40% when serum was stored at 0 degree C for 4 h. The patient's erythrocyte LD activity had normal stability at lower temperatures, but LD from other sources, when added to the patient's serum, rapidly lost activity at 0 degree C. The patient's serum contained an immunoglobulin G that combined--at 0 degree C but not at 21 degrees C--primarily with LD isoenzymes containing one or more M subunits. Because this immunoglobulin-LD complex has no enzyme activity, we used 125I-labeled purified LD to study formation of the complex. NAD+ blocked the formation of immunoglobulin-LD complex but could not dissociate the complex and restore the LD activity.

Animals↗
PubMed2003

Absence of evidence for metabolite-modulated association between alpha-glycerol-3-phosphate dehydrogenase and L-lactate dehydrogenase.

Evidence for the NADH-modulated formation of a complex between alpha-glycerol-3-phosphate dehydrogenase and l-lactate dehydrogenase was reported [Yong, H., Thomas, G. A., and Peticolas, W. L. (1993) Biochemistry 32, 11124-11131]. This NADH-modulated association suggested a mechanism of potentially great importance to enzyme modulation and the controversial phenomena of direct NADH channeling. In the present paper, we reproduce with additional controls the experiments described by Yong et al. ((1993) Biochemistry 32, 11124-11131). Our results conclusively demonstrate the absence of detectable association between alpha-glycol-3-phosphate dehydrogenase and l-lactate dehydrogenase.

Animals↗
PubMed1986

Immunological study of lactate dehydrogenase from Streptococcus mutans and evidence of common antigenic domains with lactate dehydrogenases from lactic bacteria.

Rabbit polyclonal antibodies directed against purified Streptococcus mutans L-(+)-lactate dehydrogenase reacted with the purified enzyme, giving a marked deviation of its kinetic parameters. The enzyme affinity for pyruvate or NADH decreased in the presence of antibody, the affinity for fructose 1,6-diphosphate (FDP) appeared to be slightly affected, and the cooperativity of the ligand binding was lowered. A partial protective effect was observed when the enzyme was preincubated with FDP prior to the antibody adjunction. An enzyme-linked immunosorbent assay allowed detection of a 30% decrease in enzyme-antibody fixation when FDP was added. The protective effect observed with FDP could be correlated with a conformational change induced by the activator. A decrease of antibody binding in the presence of FDP was also obtained with S. sanguis, Actinomyces viscosus, and Lactobacillus casei lactate dehydrogenases, which reflects a similar mechanism of activation among lactic bacteria. NADH did not offer any protection against antibody inhibition or fixation, and the coenzyme affinity decrease could be attributed to an indirect mechanism. On the contrary, pyruvate and the immunoglobulins apparently could compete for specific binding sites. A decrease of antibody binding was also obtained with three heterologous lactic bacterial lactate dehydrogenases, indicating a conservation of antigenic determinants implicated in the substrate binding.

Actinomyces↗
PubMed1991

Properties of D-lactate dehydrogenase from Lactobacillus bulgaricus: a possible different evolutionary origin for the D- and L-lactate dehydrogenases.

The NAD-dependent D-lactate dehydrogenase from Lactobacillus bulgaricus has been purified to homogeneity. This enzyme was a dimer made of two identical chains of molecular mass 37,000. Saturation by either substrate was hyperbolic, with Km values of 50 microM for NADH and 1 mM for pyruvate. The specific activity was 2200 units/mg and was not affected by the presence of fructose-1,6-bisphosphate, Mn2+ ions, ATP or ADP. The amino-terminal sequence determined on 50 residues showed no significant homology with known lactate dehydrogenases, suggesting that the D-lactate dehydrogenase from L. bulgaricus could not be evolutionarily related to the family of NAD-dependent L-lactate dehydrogenases.

Amino Acid Sequence↗
PubMed1994

The nucleotide and deduced amino-acid sequences of a cDNA encoding lactate dehydrogenase from Caenorhabditis elegans: the evolutionary relationships of lactate dehydrogenases from mammals, birds, amphibian, fish, nematode, plants, bacteria, mycoplasma, and plasmodium.

The nucleotide and deduced amino-acid sequences of a cDNA encoding L-lactate dehydrogenase (LDH) from nematode, Caenorhabditis elegans, were reported. This first invertebrate LDH sequence of 333 amino acids, including the initiation methionine, exhibits 63% identity with that of the most primitive vertebrate lamprey. The evolutionary relationships among 36 LDH isozymes from mammals, birds, amphibian, fish, nematode, plants, bacteria, mycoplasma and plasmodium were analyzed. The invertebrate nematode LDH is evolutionarily positioned between plant LDH and mammalian testicular LDH-C isozymes. The mammalian LDH-C isozyme appears to have arisen after the invertebrate LDH, but prior to the divergence of vertebrate LDH-A (muscle) and LDH-B (heart) isozymes as described previously.

Amino Acid Sequence↗
PubMed1987

Structure and function of L-lactate dehydrogenases from thermophilic and mesophilic bacteria, VI. Nucleotide sequences of lactate dehydrogenase genes from the thermophilic bacteria Bacillus stearothermophilus, B. caldolyticus and B. caldotenax.

Based on the previously determined amino-acid sequence of lactate dehydrogenase from B. stearothermophilus, an oligonucleotide probe was synthesized and used to clone the structural genes for lactate dehydrogenase from B. stearothermophilus, B. caldolyticus and B. caldotenax. The nucleotide sequences of the entire LDH genes from these three thermophilic bacilli were determined by the method of Maxam and Gilbert. The nucleotide sequence of the LDH gene from B. stearothermophilus is exactly identical to the one published recently; it agrees with the experimentally determined amino-acid sequence except at three positions. The amino-acid homologies among these thermophilic enzymes are 90% or more. The LDH genes are efficiently expressed in E. coli.

Amino Acid Sequence↗
PubMed1986

Use of purified lyophilized human lactate dehydrogenase isoenzymes in a study of the measurement of lactate dehydrogenase activity.

We examined the stability of human lactate dehydrogenase (EC 1.1.1.27; LD) isoenzymes 1, 2, and 3--purified to specific activities of about 200 kU/g--when lyophilized in a buffered stabilized matrix of bovine albumin. Each isoenzyme was prepared at two activity concentrations and stored at -20, 4, 20, 37, and 56 degrees C for as long as six months. LD-1 activity decayed with zero-order kinetics, LD-2 and LD-3 with first-order kinetics. The extrapolated half-lives of these preparations at -20 degrees C varied between 80 and 530 years. Stability of reconstituted samples stored at 4 degrees C was excellent for LD-1 but poor for LD-2 and LD-3. We suggest that preparations of human LD-1 be further investigated as a possible reference material.

Freeze Drying↗
PubMed1984

Macro lactate dehydrogenase: an LDH-immunoglobulin M complex that inhibits lactate dehydrogenase activity in a patient's serum.

A macro lactate dehydrogenase (LDH, EC 1.1.1.27) isoenzyme with a low total LDH activity was present in the serum of a 57-year-old woman with a drug eruption (cutaneous lesions from an allergic reaction to drug administration). The patient's LDH was shown by immunoelectrophoresis to be bound to immunoglobulin G (IgG) and M (IgM). It was found that the patient's IgM acted as an inhibitor of LDH that was specific for the M subunit. When IgM was treated with 0.1 mol/l of 2-mercaptoethanol (2-ME), the inhibiting effect of the IgM to LDH activity disappeared, while treated IgM continued to bind to the LDH molecule. The LDH activity increased approximately two-fold when the patient's serum was treated with 2-ME. LDH activity in normal human serum was inhibited and an abnormal pattern of LDH isoenzyme appeared when the patient's IgM was added to normal serum. The present case seems to be the first report of LDH-IgM complex with a marked decrease of LDH activity.

Blood Proteins↗