Glucose-6-phosphate dehydrogenase: homologous molecules in deer mouse and man

Two forms of glucose-6-phosphate dehydrogenase, A and B, have been reported in deer mouse tis sues. The B enzyme, which showed autosomally controlled polymorphism, is now found to be equally active to ward glucose-6-phosphate and galac tQse-6- phosphate; the A enzyme is specific for the former. Human and horse livers also have two forms of glucose-6-phosphate dehydrogenase which exhibit the same substrate spe cifities as those in the deer mouse. A wide variety of electrophoretic patterns was seen in the human galactose-active enzyme.     

Human-mouse somatic cell hybrids with single human chromosome (group E): link with thymidine kinase activity

Mouse somatic cells lacking thymidine kinase were mixed in culture with human diploid cells lacking hypoxanthine guanine phosphoribosyl transferase, and hybrid cells were isolated and maintained in a selective medium containing hypoxanthine, aminopterin, and thymidine. The hybrid cells at the time of isolation had karyotypes consisting predominantly of mouse chromosomes but with one human chromosome, a submetacentric member of group E, apparently giving thymidine kinase to the hybrid cell. However, after long-term propagation in the selective medium this chromosome has been lost, although cells continue to show thymidine kinase activity as demonstrated by the incorporation of (3)H-thy-midine into DNA in the hybrid cell. The hybrid cells have only mouse electro-phoretic variants for glucose-6-phosphate dehydrogenase, lactate dehydrogenase, and malate dehydrogenase, suggesting that the human genetic loci for these enzymes are not represented in the hybrid genome and may be unlinked to that for thymidine kinase.     

Dehydrogenase Activities in Dystrophic Mice

The levels of activity of glucose-6-phosphate dehydrogenase, isocitric dehydrogenase, glutathione reductase, lactic dehydrogenase, and a-glycerophosphate dehydrogenase have been studied in the gastrocnemius muscle of mice with "dystrophia muscularis." The activity of enzymes requiring triphosphopyridine nucleotide as a cofactor is increased relative to the control littermates, whereas the activity of those enzymes requiring diphosphopyridine nucleotide is decreased.     

Alpha-glycerophosphate dehydrogenase and glucose-6-phosphate dehydrogenase in tissues of the Weddell seal

High activity of alpha-glycerophosphate dehydrogenase and low activity of glucose-6-phosphate dehydrogenase in adipose tissue of Weddell seals suggest that neutral fat may be assembled there from exogenous sources of fatty acids. Low activity of glucose-6-phosphate dehydrogenase in other tissues tested precludes assignment of the function of fatty-acid synthesis to any specific tissue and emphasizes uniqueness of adipose mass in seals.     

Erythrocyte acid phosphomonesterase and glucose-6-phosphate dehydrogenase deficiency in Caucasians

Caucasian patients with erythrocyte glucose-6-phosphate dehydrogenase deficiency also have a deficiency in erythrocyte acid phosphomonoesterase. This acid phosphomonoesterase deficiency is not present in Negroes with the glucose-6-phosphate dehydrogenase deficiency.     

猪裸卵体外胞质成熟研究

[目的]改善猪裸卵的体外成熟质量,为建立稳定有效的裸卵培养体系提供科学依据。[方法]以第一极体排出比例、卵母细胞谷胱甘肽含量、亮甲酚蓝阳性率以及早期胚胎发育潜能等为主要衡量指标研究了卵泡壁颗粒细胞共培养对猪裸卵胞质成熟的影响。[结果]体外成熟结果表明,相对于DO组,DO+MGC组卵母细胞排除第一极体的比例无显著差异,但核成熟的进程得到了改善,更接近于COC组;成熟卵母细胞GSH含量检测结果表明,DO+MGC组平均每个卵母细胞谷胱甘肽含量(光密度1 053.67)与COC组(1 426.00)和COC+GC组(1 541.00)差异不显著,但DO组(724.67)显著低于COC组和COC+GC组(P0.05);G6PDH活性检测结果表明,DO+MGC组BCB阳性卵母细胞比例(88.26%)与COC组(92.75%)以及DO组(82.86%)差异均不显著,但DO组显著低于COC组(P0.05);成熟卵母细胞孤雌激活后的发育结果表明,DO+MGC组卵裂率(94.98%)和囊胚率(43.67%)显著高于DO组卵裂率(52.54%)和囊胚率(8.97%),与COC组卵裂率(97.11%)和囊胚率(38.30%)差异不显著(P0.05);成熟卵母细胞体外受精后的发育结果表明,DO+MGC组卵裂率(72.65%)与DO组卵裂率(63.59%)无显著差异,但DO+MGC组囊胚率(17.79%)显著高于DO组(9.88%)(P0.05)。[结论]卵泡壁颗粒细胞共培养可以显著改善裸卵体外成熟的胞质成熟质量并进而提高后续发育潜力。     

Cyclic changes in enzyme activity in synchronized mammalian cell cultures

Activity of the enzymes glucose-6-phosphate dehydrogenase and lactate dehydrogenase increases intermittently in synchronized cultures of Chinese hamster cells. During G(1) phase (3 hours after mitosis), midway through S phase (7 hours after mitosis) and again in late S phase (10 hours after mitosis), rapid increases in activity were observed and correlated with a net increase in cell size and total protein. The evidence suggests that this is a general phenomenon which affects a whole population of proteins and may be the expression of an endogenous cellular rhythm.     

低温胁迫下黑龙江林蛙肝脏酶活性变化

初步分析了低温胁迫下黑龙江林蛙肝脏超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)、6-磷酸葡萄糖脱氢酶(G6PDH)及酯酶(EST)酶活性的变化.结果表明:1℃组的黑龙江林蛙肝脏SOD、LDH-1及EST的酶活性显著高于14℃组(P＜0.05),而2组的LDH、G6PDH及EST总酶比活力无显著性差异.为适应低温环境,黑龙江林蛙肝脏某些酶活性显著增加,维持了机体代谢的稳定.     

猪裸卵体外胞质成熟研究(英文)

[目的]改善猪裸卵的体外成熟质量,为建立稳定有效的裸卵培养体系提供科学依据。[方法]以第一极体排出比例、卵母细胞谷胱甘肽含量、亮甲酚蓝阳性率以及早期胚胎发育潜能等为主要衡量指标研究了卵泡壁颗粒细胞共培养对猪裸卵胞质成熟的影响。[结果]体外成熟结果表明,相对于DO组,DO+MGC组卵母细胞排除第一极体的比例无显著差异,但核成熟的进程得到了改善,更接近于COC组;成熟卵母细胞GSH含量检测结果表明,DO+MGC组平均每个卵母细胞谷胱甘肽含量(光密度1053.67)与COC组(1426.00)和COC+GC组(1541.00)差异不显著,但DO组(724.67)显著低于COC组和COC+GC组(P<0.05);G6PDH活性检测结果表明,DO+MGC组BCB阳性卵母细胞比例(88.26%)与COC组(92.75%)以及DO组(82.86%)差异均不显著,但DO组显著低于COC组(P<0.05);成熟卵母细胞孤雌激活后的发育结果表明,DO+MGC组卵裂率(94.98%)和囊胚率(43.67%)显著高于DO组卵裂率(52.54%)和囊胚率(8.97%)(P<0.05),与COC组卵裂率(97.11%)和囊胚率(38.30%)差异不显著;成熟卵母细胞体外受精后的发育结果表明,DO+MGC组卵裂率(72.65%)与DO组卵裂率(63.59%)无显著差异,但DO+MGC组囊胚率(17.79%)显著高于DO组(9.88%)(P<0.05)。[结论]卵泡壁颗粒细胞共培养可以显著改善裸卵体外成熟的胞质成熟质量并进而提高后续发育潜力。     

Glucose-6-phosphate dehydrogenase deficient red cells: resistance to infection by malarial parasites

Erythrocyte mosaicism occurs in females heterozygous for glucose-6-phosphate dehydrogenase deficiency. In blood from female children with acute Plasmodium falciparum malaria the parasite rate was 2 to 80 times higher in normal than in deficient erythrocytes. This may be the mechanism whereby the gene for glucose-6-phosphate dehydrogenase deficiency confers selective advantage against malaria to heterozygous females, and thus may have attained the polymorphic frequency occurring in populations living in areas with endemic malaria.     

Human phosphoglycerate kinase and inactivation of the X chromosome

The fibroblasts derived from the skin of a woman heterozygous for an X-linked deficiency of phosphoglycerate kinase represented a mosaic. Two of 22 clones with normal glucose-6-phosphate dehydrogenase activity and hypoxanthine(guanine) phosphoribosyltransferase activity had no phosphoglycerate kinase activity detected by electrophoresis. Because the loci for glucose-6-phosphate dehydrogeniase and hypoxanthine(guanine)phosphoribosyltransferase are already known to undergo inactivation and to be on the short arm of the X chromosome and the locus for phosphoglycerate kinase is on the long arm, these observations support the conclusion that the entire human X chromosome can be involved in X inactivation.     

孕鼠DEHP暴露影响胎儿早期卵母细胞H3K27me3表达的研究

本文以胎鼠卵母细胞为研究对象,分析了妊娠母鼠孕期暴露邻苯二甲酸二(2-乙基)己酯(DEHP)对胎鼠卵母细胞早期发育过程中组蛋白甲基化修饰程度的影响,结果发现:妊娠母鼠在12.5 dpc到16.5 dpc 期间暴露40 μg/kg DEHP,第一次减数分裂前期的胎鼠雌性生殖细胞的H3K27me3表达受到了显著影响,导致H3K27me3强阳性细胞比例显著减少.该研究结果说明DEHP可通过孕鼠影响胎鼠卵母细胞早期发育过程中的组蛋白甲基化修饰.     

Sex-linkage of erythrocyte glucose-6-phosphate dehydrogenase in two species of wild hares

Glucose-6-phosphate dehydrogenase specific to the erythrocytes of each of two wild hares found in Europe was discerned by starch-gel electrophoresis at pH 7.0 and pH 8.6. The single, sharp band of the dehydrogenase of Lepus europaeus was faster than that of L. timidus, at both pH levels. The sex-linkage of this enzyme was tested through reciprocal hybrids between the two species. Each male hybrid had a single band of enzyme identical with that of its mother, while both parental types of this enzyme coexisted in female hybrids. Thus, sex-linkage of glucose-6-phosphate dehydrogenase has been suggested not only in man and in the family Equidae, but now in the family Leporidae of placental mammals as well.     

Effect of galactose-1-phosphate on glucose oxidation by normal and galactosemic leukocytes

During incubation with galactose, galactosemic leukocytes accumulated more galactose-l-phosphate than did normal leukocytes. Concomitant determination of glucose oxidation, with C(14) glucose, revealed no inhibition of the hexosemonophosphate pathway. These results are at variance with recent studies in rat lens tissue, which suggests that intracellular galactose-1-phosphate depressed glucose-6-phosphate dehydrogenase activity and the oxidative pathway.     

小鼠卵母细胞的孤雌激活与ES细胞样集落分离

对小鼠卵母细胞进行孤雌激活用于单性生殖研究。取成年昆明白小鼠进行超数排卵,乙醇激活,同小鼠输卵管上皮细胞共培养并添加mM16培养基培养至早期囊胚阶段,移至小鼠胎儿成纤维细胞饲养层上,换成ES细胞培养液继续培养,分离消化ICM,重新接种,对分离出的ES样细胞集落进行分离培养鉴定。结果显示,小鼠卵母细胞激活率为96.99%,2-细胞发育率为93.17%,桑椹胚发育率为80.33%,囊胚发育率为73.22%。小鼠孤雌激活囊胚中分离的ES样细胞集落具有一系列ES细胞所特有的特征,如呈现出岛屿状形态,碱性磷酸酶染色为阳性,体外能够自发分化成上皮样或单个散在分布的细胞等。试验证明,小鼠孤雌胚中可以分离出ES细胞样集落。     

Glucose-6-phosphate dehydrogenase and detoxification of hydrogen peroxide in human erythrocytes

Human erythrocytes with deficient glucose-6-phosphate dehydrogenase levels are unable to maintain their levels of reduced glutathione in the presence of low-level, steady-state concentrations of hydrogen peroxide. This finding has bearing on the biochemical mechanisms of drug-induced hemolytic anemia.     

Structure-disrupting ions: detection of qualitative change in an enzyme

Preparations of erythrocyte glucose-6-phosphate dehydrogenase from normal individuals show similar degrees of inhibition by neutral salts. Preparations from Caucasian subjects with different hereditary deficiency syndromes differ from each other and from normal subjects, indicating a qualitative difference in these specific "deficient" enzymes. Sensitivity to neutral salts may be a means of detecting an amino acid substitution.     

乌江上游四川裂腹鱼和昆明裂腹鱼5种同工酶的比较

采用聚丙烯酰胺凝胶垂直平板电泳法(PAGE)对四川裂腹鱼和昆明裂腹鱼4种组织(肌肉、肝脏、尾鳍和性腺)的5种同工酶(LDH、MDH、ADH、EST和G-6-PDH)进行比较研究,对5种同工酶在2种鱼的组织分布、位点表达及酶谱表型作了对比分析。结果表明:LDH、MDH、ADH、EST和G6PDH 5种同工酶酶谱表型和酶带的活性在种间和种内不同组织中均表现出一定差异。同时依据其同工酶酶谱表达的复杂性和个体间多样性,探讨功能重复基因和哑基因存在的可能。     

猪体内囊尾蚴发育过程中能量代谢酶组织化学观察

采用酶组织化学技术半定量观察猪体内囊尾蚴发育过程中乳酸脱氢酶 (L DH)、琥珀酸脱氢酶 (SDH)、谷氨酸脱氢酶 (GDH)、三磷酸腺苷酶 (ATPase)、酸性磷酸酶 (ACP)、碱性磷酸酶 (AKP)、6 -磷酸葡萄糖酶 (G6 Pase)、黄嘌呤氧化酶 (XOD)、脂酶 (FE)活性的变化。结果表明 ,随虫体发育 SDH,FE,ACP,AKP,ATPase活性升高 ,L DH,GDH,XOD无明显变化 ,未显示 G6 Pase活性。结果揭示随虫体生长发育糖类与脂类分解产生能量的代谢通路及物质转运途径增强 ,乳酸酵解、氨基酸分解、核苷酸分解途径无明显变化 ,虫体可能不具有糖异生作用。     

Athens variant of glucose-6-phosphate dehydrogenase

A variant of glucose-6-phosphate dehydrogenase (G6PD), characterized by slower than normal electrophoretic migration and associated with mild deficiency of G6PD in the red cells, was detected in two unrelated Greek males. Electrophoretic, chromatographic, and enzymologic study indicated that the new mutant is structurally different from normal G6PD (B+) and from the Mediterranean variant associated with red-cell enzyme deficiency (B-). Convincing electrophoretic separation of the new variant from the normal B+ and the Mediterranean B- enzymes was achieved only by detailed electrophoretic study in different buffer systems and conditions.