The effects of near infrared radiation on rats assessed by succinate dehydrogenase activity in lymphocytes in blood smears

The biological effects of near infrared radiation (850 nm) modulated by an acoustic frequency of 101 Hz were studied. The study was conducted on rats; the effect was registered by succinate dehydrogenase activity in lymphocytes in blood smears after the administration of an activating dose of adrenaline, which simulates the state of the organism at early stages of a pathogenic action (stress). A pronounced regulating effect of infrared radiation on the activity of succinate dehydrogenase in animals that were activated by adrenaline was shown. Infrared radiation has a normalizing effect via the reduction of the degree of inhibition or activation of the enzyme induced by adrenaline and has no effect on the control animals. Thus, by modulation of the activity of succinate dehydrogenase, infrared radiation regulates energy production in mitochondria that is provided by the most potent oxidation substrate, viz., succinic acid; the effect is especially pronounced under stress.     

The activity of Krebs cycle enzymes in the visual analyzer of normal rats and under stress]

In the visual analyzer of the intact animals higher activity of NAD-dependent dehydrogenases of tricarbonic acids cycle is observed in the retina and of FAD-dependent dehydrogenases in the occipital brain lobes. The influence of stress by Desiderato method elicits compensatory increase of the succinatedegidrogenase activity. The acute stress elicits a change of regulation of the activity of dehydrogenase of tricarbonic acids cycle, estimated by the reaction to functional load. Animals staying in the darkness after stress promotes restoration of the tricarbonic acids cycle of the enzymes activity up to the normal level.     

轻度水分胁迫的小麦幼苗中与呼吸有关的几种酶活性变化

轻度水分胁迫使小麦幼苗叶片呼吸升高时,叶中琥珀酸去氢酶和细胞色素氧化酶活性均明显升高;而同样胁迫使根呼吸下降时,根中这两种酶活性均明显下降。叶和根中ATP酶分解活性在胁迫下都明显升高。轻度水分胁迫使叶片过氧化氢酶活性升高。叶中有明显的乙醇酸氧化酶活性,抗旱品种的酶活性较高,胁迫使此酶活性降低。     

过量表达苹果酸脱氢酶对大肠杆菌NZN111产丁二酸的影响

大肠杆菌NZN111是敲除了乳酸脱氢酶的编码基因 (ldhA) 和丙酮酸-甲酸裂解酶的编码基因 (pflB) 的工程菌,厌氧条件下由于辅酶NAD(H) 的不平衡导致其丧失了代谢葡萄糖的能力。构建了苹果酸脱氢酶的重组菌大肠杆菌NZN111/pTrc99a-mdh,在厌氧摇瓶发酵过程中通过0.3 mmol/L的IPTG诱导后重组菌的苹果酸脱氢酶 (Malate dehydrogenase,MDH) 酶活较出发菌株提高了14.8倍,NADH/NAD+的比例从0.64下降到0.26,同时NAD+和NADH浓度分别     

The effect of thioctic acid on the activity of the antioxidant glutathione-dependent system under conditions of toxic hepatitis in rats

The effect of thioctic acid on functioning of the antioxidant glutathione-dependent system and activity of enzymes, supplying this system with NADPH, were studied under conditions of toxic hepatitis in rats. A decrease in the glutathione reductase and glutathione peroxidase activities towards normal levels was observed in animals with toxic hepatitis after administration of thioctic acid. Administration of thioctic acid under conditions of toxic hepatitis caused a decrease in the NADPH-dependent isocitrate dehydrogenase and glucose-6-phosphate dehydrogenase activities; this evidently reflects lowered requirements in the NADPH supply for operation of the glutathione-dependent system. Thus, these studies have shown that thioctic acid may serve as a factor regulating the extent of the oxidative stress development and the state of the glutathione antioxidant system.     

A histochemical study on the correlation between secretory activity and the TCA cycle in the gland cell

Summary The activity of succinic dehydrogenase and malic dehydrogenase was observed histochemically in the gland stomach of rats, and also the relationship between the secretory activity of the gastric gland cells and the process of the TCA cycle in the cells was studied.Histochemically, enzyme activity is plainly visible in the gastric parietal cells but in the gastric chief cells and mucous neck cells.The secretory activity of the cells was promoted by the administration of food, the sub-cutaneous injection of histamine, histidine, acetylcholine or eserin.The activity of succinic dehydrogenase appears to be constant regardless of secretory activity except in a few cases. The activity of malic dehydrogenase increases as secretory activity is promoted. It seems very unlikely that one step in the cycle (the transformation of malic acid into oxalacetic acid) would be accelerated while the other step (the transformation of succinic acid into fumaric acid) is not. This inconsistency of activity may be attributed to the histochemical reaction. Thus the increase of malic dehydrogenase activity is seen as an acceleration of the whole TCA cycle. It is our conclusion, therefore, that the source of energy within the cell, i.e. the TCA cycle, is a process which parallels secretory activity.     

Cardiomyocytes of the left ventricle of the heart in experimental infarct and pharmacostimulation (histochemical study)

Contents and activity of lactate dehydrogenase and succinic dehydrogenase of cardiomyocytes have been studied histochemically and cytophotometrically in the left ventricle of the rabbit heart under conditions of myocardial infarction experimentally induced by alpha-tocoferol and sodium nucleinate. The substances mentioned produce a protective effect on the energic metabolism of cardiomyocytes.     

Study of some oxidoreductases in nerve tissue culture]

A change in the activity of succinic dehydrogenase, of the NAD- and NADP-diaphorases was studied in the dissociated culture of the cerebellum of neonatal rats under the effect of immune serum of the animals with an experimental allergic pertussis encephalomyelitis. There was revealed an increase in the activity of oligodendrocytes following a 3-hour exposure with the immune serum and a reduction of the activity of the enzymes under study in the same cells after a 12-hour exposure of the cultures with the serum. In difference from oligodendrocytes, the astrocytes displayed a high activity of all the enzymes under study after a 12-hour exposure.     

Enhanced steroidogenesis in hen ovary after malonate administration.

The activities of glucose-6-phosphate dehydrogenase, delta 5-3 beta-hydroxysteroid dehydrogenase and succinic dehydrogenase have been studied histochemically in the ovary of normal and malonate treated hens. Following malonate treatment, glucose-6-phosphate dehydrogenase and delta 5-3 beta-hydroxysteroid dehydrogenase showed increased activities while succinic dehydrogenase activity was diminished significantly. The significance of the above changes has been discussed. The ascorbic acid and cholesterol contents of the ovary were determined to get additional information about steroidogenesis in the gland under such treatment.     

Purification and properties of two succinic semialdehyde dehydrogenases from Klebsiella pneumoniae

Two forms of succinic semialdehyde dehydrogenase have been isolated in Klebsiella pneumoniae M5a1. The two enzymes could be separated by filtration on Sephacryl S-300 and their apparent molecular weights were approx. 275,000 and 300,000. The large enzyme is specific for NADP. The smaller enzyme, which is induced by growth on 3-hydroxyphenylacetic acid, 4-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid and gamma-aminobutyrate, has been purified to 96% homogeneity by affinity chromatography. The NAD-linked succinic semialdehyde dehydrogenase was able to use NADP as cofactor. Its induction is coordinated with 3- and 4-hydroxylase, the enzymes which initiate degradation of 3- and 4-hydroxyphenylacetic acid. The NAD-linked form is also induced by exogenous succinic semialdehyde. The large enzyme is specific for NADP and has been isolated from a defective mutant which lacked the activity of the NAD-linked succinic semialdehyde dehydrogenase. Activity and stability conditions and true K m values for substrates and cosubstrates of the two enzymes were determined. Some aspects of the induction of the NAD-linked enzyme participating in the metabolism of 4-hydroxyphenylacetic and gamma-aminobutyrate were studied.     

谷氨酸棒状杆菌厌氧产丁二酸的发酵条件

考察谷氨酸棒状杆菌ATCC13032Δldh厌氧产丁二酸的发酵条件。结果发现:补加NaHCO3的效果最好,并且考察了NaHCO3浓度对葡萄糖转化速率及丁二酸生成速率的影响。运用代谢流分析方法分析了乳酸脱氢酶基因敲除对谷氨酸棒状杆菌厌氧代谢的影响,发现乳酸脱氢酶基因敲除导致磷酸烯醇式丙酮酸生成丁二酸的流量提高了214.3%,流向乳酸的流量变为0;分批厌氧转化36 h生成41.2 g/L丁二酸,产率45.0%。     

Structuro-kinetic organization of the tricarboxylic acid cycle in the active functioning of mitochondria

Taking into account structural and functional organization of mitochondrial processes it has been shown that at active work there functions in mitochondria an accelerated mechanism of succinic acid formation via coupling of glutamate-oxalacetate transaminase and alpha-ketoglutaratdehydrogenase. This way is closed up into a cycle with the participation of cytosol transaminases which support influx of glutamate, pyruvate and malic acid into mitochondria. When provision of the mitochondria with the substrate proceeds along the transaminase pathway the initial slow region of the tricarboxylic acid cycle is omitted. Thus at active work a faster course is selected. It permits realization of the advantages of succinate dehydrogenase high activity and of oxidation efficiency of succinic acid generated in mitochondria which is essentially higher than that under oxidation of succinic acid and even more of other substrates of the tricarboxylic acid cycle.     

TCA循环中间产物对酿酒酵母胞内代谢关键酶活性的影响

对酿酒酵母在添加苹果酸、柠檬酸和琥珀酸的混合培养基与其在YEPD培养基中胞内丙酮酸激酶、葡萄糖-6-磷酸脱氢酶、异柠檬酸脱氢酶、苹果酸脱氢酶、乙醇脱氢酶的酶活力差异进行了对比分析。结果表明:添加苹果酸使胞内丙酮酸激酶、异柠檬酸脱氢酶、苹果酸脱氢酶、乙醇脱氢酶的酶活分别下降34.82%、57.23%、39.15%、12.10%;添加柠檬酸使胞内丙酮酸激酶、异柠檬酸脱氢酶、苹果酸脱氢酶的酶活分别下降50.17%、42.20%、48.40%;添加琥珀酸使胞内丙酮酸激酶、葡萄糖-6-磷酸脱氢酶、异柠檬酸脱氢酶、苹果酸脱氢酶、乙醇脱氢酶的酶活分别下降34.16%、34.16%、50.87%、50.87%、12.37%。丙酮酸激酶、异柠檬酸脱氢酶和苹果酸脱氢酶对3种有机酸的耐受性较差,葡萄糖-6-磷酸脱氢酶、乙醇脱氢酶对3种有机酸的耐受具有选择性。     

Tri-iodothyronine enhances the formation of light mitochondria during cold exposure

The effect of cold exposure and of PTU and PTU + T3 administration on the protein content and succinic dehydrogenase activity of three mitochondrial populations obtained from rat liver was examined. Our results indicated the following: Succinic dehydrogenase activity increases mainly in the light mitochondrial fraction of cold-exposed rats. PTU administration of cold-exposed animals does not affect the increment in enzyme activity of the heavy fraction but blocks the increment of the light fraction. PTU + T3 administration restores succinic dehydrogenase activity to the values prevalent in normal cold-exposed rats. These findings suggest that thyroid hormone may stimulate the formation of light mitochondria during cold exposure.     

Metabolism of the anaerobic formation of succinic acid bySaccharomyces cerevisiae

1. Succinic acid is formed in amounts of 0.2–1.7 g/l by fermenting yeasts of the genusSaccharomyces during the exponential growth phase. No differences were observed between the various species, respiratory deficient mutants and wild type strains.
2. At low glucose concentrations the formation of succinic acid depended on the amount of sugar fermented. However, the nitrogen source was found to be of greater importance than the carbon source.
3. Of all nitrogen sources, glutamate yielded the highest amounts of succinic acid. Glutamate led to an oxidative and aspartate to a reductive formation of succinic acid.
4. A reductive formation of succinic acid by the citric acid cycle enzymes was observed with malate. This was partially inhibited by malonate. No evidence was obtained that the glyoxylate cycle is involved in succinic acid formation by yeasts.
5. Anaerobically grown cells ofSaccharomyces cerevisiae contained α-ketoglutarate dehydrogenase. Its activity was found in the 175000 x g sediment after fractionated centrifugation. The specific activity increased 6-fold after growth on glutamate as compared with cells grown on ammonium sulfate.
6. The specific activities of malate dehydrogenase, fumarase, succinate dehydrogenase, succinylcoenzymeA synthetase, α-ketoglutarate dehydrogenase and glutamate dehydrogenase (nicotinamide adenine dinucleotide dependent) were determined in yeast cells grown on glutamate or ammonium sulfate. Similar results were obtained with a wild type strain and a respiratory deficient mutant. The latter did not contain succinate dehydrogenase.
7. In fermenting yeasts succinic acid is mainly formed from glutamate by oxidation.

     

Strain variation in Hymenolepis diminuta: enzyme profiles

In comparative study of respiratory metabolism, it was established that the relative proportions of respiratory end-products (succinic, acetic and lactic acids) differed consistently in two strains of Hymenolepis diminuta (Toronto and ANU). The ANU strain produced more lactic acid and less succinic acid under aerobic and anaerobic conditions. In the shift from aerobic to anaerobic conditions both strains compensated by increasing their outputs of succinic acid. The ANU strain possessed significantly higher activities of hexokinase, pyruvate kinase, lactate dehydrogenase, cytosolic and mitochondrial malic enzyme and cytosolic α-glycerophosphate dehy drogenase. The Toronto strain had significantly higher activities of fumarase, succinate dehydrogenase, and fumarate reductase. There were no significant differences in the activities of phosphoenolpyruvate carboxykinase and malic dehydrogenase between strains. The fumarase activity in the Toronto strain was 16 times that of the ANU strain, its K_m (malate) was 0.8mM, as opposed to 2.5 mM, and it was less sensitive to inhibition by NAD or ATP. These observations are consistent with the patterns of end-product formation in the two strains. Ratios of end-products and calculations of approximate redox balance suggest that the Toronto strain may have a greater capacity for aerobic metabolism.     

Adaptive evolution improves acid tolerance and succinic acid production in Actinobacillus succinogenes

Fermentation at low pH is an efficient way to improve the competitiveness of biological succinic acid-producing process. Actinobacillus succinogenes shows good performance of succinic acid production under anaerobic conditions, but its succinic acid production capability at the low-pH is inefficient due to the poor acid resistance. Herein, a mutant A. succinogenes BC-4 with improved cell growth and succinic acid production under weak acid conditions was obtained by adaptive evolution. The specific growth rate and succinic acid production of BC-4 reached 0.13 g/L/h and 20.77 g/L, which were increased by 3.25- and 2.95- fold, respectively compared with the parent strain under anaerobic condition at pH 5.8. The activities of specific enzymes with ATP generation were significantly enhanced under weak acidic conditions, resulting in 1.28-fold increase in the maximum ATP level. Membrane fatty acid composition analysis demonstrated that the ratio of saturated to unsaturated fatty acids was decreased from 1.62 to 1.44 in mutant BC-4, leading to improved intracellular pH homeostasis. Furthermore, the change from long-chain to median-chain fatty acid might lower the permeability of H⁺ into cytoplasm for survival under acid stress. These results indicated that A. succinogenes BC-4 is a promising candidate for succinic acid production under weak acid condition.     

Lymphocyte and neutrophil cytochemistry in the dynamics of different forms of diphtheria in adults]

The cytochemical study of lymphocytes and neutrophils isolated from fractionated blood of diphtheria patients and carriers has revealed that a decrease in the activity of lymphocyte succinic dehydrogenase and myeloperoxidase can be observed at all periods of the disease and in all its forms. A decrease in the activity of lymphocyte nonspecific esterase has been noted only in patients with toxic and subtoxic diphtheria and a decrease in the activity of neutrophil alkaline phosphatase, in carriers. The analysis of correlations between the parameters of five enzymes under study (lymphocyte succinic dehydrogenase, lymphocyte acid phosphatase, lymphocyte non-specific esterase, myeloperoxidase, neutrophil alkaline phosphatase) and enzymatic rosette parameters has been made. The analysis has revealed an essential increase in the number of correlations in comparison with donors, changes in the qualitative nature of these correlations and sometimes the reversion of the correlations. Carriers have shown the greatest number of correlations. By the end of the terms of observations no restoration of normal correlations has been observed.     

Myonic makeup of the muscles innervated by the vagus nerve

Histochemical investigation on succinic dehydrogenase activity and morphometric studies have demonstrated certain differences in the dog sublingual group of muscles. The thyreohyoid and sternohyoid muscles innervated by spinal nerves possess three types of myons differing in succinic dehydrogenase activity and in the area of transversal section. The cricothyreoid muscle and the superior pharyngeal constrictor obtaining their motor innervation from the vagus nerve are composed of unitypical muscular fibres with nearly the same areas of transversal section and high enzymic activity. The differences noted should be explained by different sources of motor innervation.     

Comparative toxicity of trivalent and hexavalent chromium to rabbits. III. Biochemical and histological changes in testicular tissue.

The administration of trivalent and hexavalent chromium compounds produced inhibition of the activity of succinic dehydrogenase, adenosine triphosphatase and acid phosphattase accompanied by cellular degeneration with complete absence of spermatocytes in the testis of rabbits. The biochemical and histological changes were more marked in the animals treated with the trivalent chromium than those exposed to hexavalent chromium and were progressive with the duration of exposure.