• BMB Reports
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• v.38 no.5
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• pp.584-590
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• 2005

Glucose 6-phosphate dehydrogenase (EC 1.1.1.49) was purified from Aspergillus aculeatus, a filamentous fungus previously isolated from infected tongue of a patient. The enzyme, apparently homogeneous, had a specific activity of $220\;units\;mg^{-1}$/, a molecular weight of $105,000{\pm}5,000$ Dal by gel filtration and subunit size of $52,000{\pm}1,100$ Dal by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The substrate specificity was extremely strict, with glucose 6-phosphate (G6P) being oxidized by nicotinamide adenine dinucleotide phosphate (NADP) only. At assay pH of 7.5, the enzyme had $K_m$ values of $6\;{\mu}m$ and $75\;{\mu}m$ for NADP and G6P respectively. The $k_{cat}$ was $83\;s^{-1}$. Steady-state kinetics at pH 7.5 produced converging linear Lineweaver-Burk plots as expected for ternary-complex mechanism. The patterns of product and dead-end inhibition suggested that the enzyme can bind NADP and G6P separately to form a binary complex, indicating a random-order mechanism. The enzyme was irreversibly inactivated by heat in a linear fashion, with G6P providing a degree of protection. Phosphoenolpyruvate (PEP), adenosinetriphosphate (ATP), and fructose 6-phosphate (F6P), in decreasing order, are effective inhibitors. Zinc and Cobalt ions were effective inhibitors although cobalt ion was more potent; the two divalent metals were competitive inhibitors with respect to G6P, with $K_i$ values of $6.6\;{\mu}m$ and $4.7\;{\mu}m$ respectively. It is proposed that inhibition by divalent metal ions, at low NADPH /NADP ratio, is another means of controlling pentosephosphate pathway.

• Korean Journal of Pharmacognosy
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• v.22 no.4
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• pp.225-232
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• 1991

The hypoglycemic and metabolic effects of Commelina communis L. extract were investigated in alloxan-diabetic rats. The increased blood glucose level in the diabetic rats was significantly lowered and the loss of body weight in the diabetic rats was recovered with the treatments of the crude extract. Administration of the extract elicited the significant increase of glucose-6-phosphate dehydrogenase activity and liver weight which were decreased in the alloxan-treated rat serum and liver. On the other hand, the kidney weight and glucose-6-phosphate dehydrogenase activity were increased in the alloxan treated rat kidney and were potentiated by the treatment of the extract. In both liver and kidney, together with serum, alkaline phosphatase and ATPase activities were increased in the alloxan diabetic rats and were not recovered, rather potentiated by the administration of the extract.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.682-687
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• 2020

This study was performed to investigate the antidiabetic effect of ethanol extract of Phelladrindron Amurense Rupr (P.A) in Streptozotocin(STZ) induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45mg/kg,b.w. dissolved in citrate buffer. The ethanol extract of P. A was orally administrated once a day for 7 days at a dose of 1,000mg/kg. The content of serum glucose, was significantly decreased in P.A treated group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucokinase(GK) and glucose-6-phosphate dehydrogenase(G-6-PDH) were significantly increased(p<0.05), and activity of glucose-6-phoshatase(G-6-Pase) was significantly decreased(p<0.05) in P.A treated group compared to those of STZ-control group, These results indicated that ethanol extract of P.A have antidiabetic effect in STZ-induced diabetic rats.

• Journal of Plant Biology
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• v.12 no.2
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• pp.15-22
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• 1969

By spectrophotometric assay method, the following enzymes could be detected in Dunaliella tertiolecta and Chlorella pyrenoidosa cell-free extracts: Hexokinase; Glucose-6-phosphate, 6-Phosphogluconate and Triosephosphate dehydrogenase; Transketolase; Phosphogluco and Ribosephosphate isomerase; Phosphoglucomutase; Phosphofructokinase; Fructosediphosphate aldorase and Ribulosephosphate 3-epimerase. Such enzymes are in accordance with the proposed pathway of glucose catabolism by D. tertiolecta as well as C. pyrenoidosa. Also, it could be estimated, under the presence of NADP, that pentose phosphate pathway were more active than glycolytic pathway in D. tertiolecta cell-free systems.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.189.4-190
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• 1976

glucose-6-phosphate dehydrogenase를 생산하는 Leuconostoc속 균주를 김치로부터 약 500주 분리하여 그 중 활성이 가장 강한 한주를 분리하여 동정한 결과 Leuconostoc mesenteroides였다. 이 균주로부터 몇가지 효소생산 조건을 실험하여 다음과 같은 결과를 얻었다.(결과)

• Clinical and Experimental Reproductive Medicine
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• v.22 no.3
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• pp.301-307
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• 1995

소 체외수정란에 있어서 pentose phosphate pathway (PPP)를 연구하기 위해서, 한개의 체외수정란으로부터 glucose 6-phosphate dehydrogenase (G6PDH)의 활성을 효소증폭방법으로 측정하였다. Glucose 6-phosphate (G6P) 기질을 처리하지 않은 2, 4, 8세포기, 상실배 및 배반포기 수정란에서의 G6PDH 활성치는 각각 $25.5{\pm}3.3$, $27.8{\pm}3.4$, $40.9{\pm}6.2$, $34.9{\pm}3.6$ 및 $52.9{\pm}2.5{\times}10^{-8}mol/embryo/h$ 을 나타내었다. 즉, 8 세포기 이후 수정란들은 2 세포기나 4 세포기보다도 높은 효소활성치를 보여주었다 (P<0.01). 그리고 G6P 기질을 첨가한 2,4,8 세포기, 상실배기 및 배반포기 수정란의 G6PDH 활성치는 각각 $32.3{\pm}3.9$, $29.4{\pm}1.8$, $51.9{\pm}4.2$, $42.6{\pm}2.7$ 및 $52.9{\pm}2.5{\times}10^{-8}mol/embryo/h$ 로서 기질 무처리구와 마찬가지로 유의성이 인정되었다 (P<0.01). 전반적으로 수정란의 발달단계에 있어서 G6P 첨가한 수정란들에 G6PDH의 효소활성치가 기질을 처리하지 수정란들의 것보다도 높은 경향을 보였다. 한편, 소 체외수정란의 G6PDH 효소활성치와 발생능과의 관계를 알아보기 위하여, 4 세포기 수정란들을 효소활성치의 정량적 수준 (low, middle, high)에 따라 3 군으로 분류한 다음 $38.5^{\circ}C$, 5% $CO_2$에서 5일간 난구세포들과 공동배양을 실시하였다. 그 결과, G6PDH 효소활성치 차이에 따른 수정란들의 체외발달율에는 유의성이 인정되지 않았다. 본 실험의 결과를 종합하여 볼 때, 소 체외수정란에 있어서 PPP 대사는 8세포기 이후부터 활발히 이루어지고 있음을 알 수 있었다.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.48-64
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• 2002

The primary recognized health risk from common deficiencies in glucose-6-phosphate dehydrogenase (G6PD), a cytoprotective enzyme for oxidative stress, is red blood cell hemolysis. Here we show that litters from untreated pregnant mutant mice with a hereditary G6PD deficiency had increased prenatal (fetal resorptions) and postnatal death. When treated with the anticonvulsant drug phenytoin, a human teratogen that is commonly used in pregnant women and causes embryonic oxidative stress, G6PD-deficient dams had higher embryonic DNA oxidation and more fetal death and birth defects. The reported G6PD gene mutation was confirmed and used to genotype fetal resorptions, which were primarily G6PD deficient. This is the first evidence that G6PD is a developmentally critical cytoprotective enzyme for both endogenous and xenobiotic-initiated embryopathic oxidative stress and DNA damage. G6PD deficiencies accordingly may have a broader biological relevance as important determinants of infertility, in utero and postnatal death, and teratogenesis.-Nicol, C. J., Zielenski, J., Tsui, L.-C., Wells, P. G. An embryoprotective role for glucose-6-phosphate dehydrogenase in developmental oxidative stress and chemical teratogenesis.

• Parasites, Hosts and Diseases
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• v.33 no.4
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• pp.331-340
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• 1995

Interstrain polymorphisms of isoenzyme profiles and mitochondrial (Mt) DNA fingerprints were observed among seven strains of Acnnthnmoeba isolated from different sources and morphologically assigned to A. polvphngn. Mt DNA ringerprints by eight restriction endonucleases (Bgl II, Sca I, Cla I, EcoR I, Xbo I, Kpn I, Sal I, and Sst I) revealed considerable interstrain polymorphisms . Isoenzyme profiles revealed considerable interstrain polymorphisms for acid phosphatase, lactate dehydrogenase, and glucose-6- phosphate dehydrogenase while those for glucose phosphate isomerase , leucine aminopeptidase , and malate dehydrogenase showed similarity Despite of the interstrain polymorphisms, the isoengyme profiles and Mt DNA fingerprints of the strain Ap were found to be identical with those of the strain .tones . Mt DNA fingerprinting was found to be highly applicable for the strain identification, characterization, and differentiation. Key words: Acanthnmoebn polyphcga, interstrain polymorphism, isoenzyme profiles , Mt DNA fingerprints, strain differentiation, strain identification.

• Journal of Ginseng Research
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• v.21 no.3
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• pp.174-186
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• 1997

In this study, rat hepatocytes known to have active carbohydrate metabolism were obtained by using the liver perfusion technique to examine the hypoglycemic action of red ginseng saponin components [ginsenoside (mixture, $Rb_1$, and $Rg_1$)] and incubated in two different media-one containing insulin and glucagon (control group), and the other containing glucagon only, The specific activities of some regulatory enzymes such as glucokinase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and glucose 6-phosphatase, in main pathways which were directly related to the glucose metabolism were compared between these two kinds of hepatocytes cultured in two different media. The effects of red ginseng saponin components [ginsenoside (mixture, $Rb_1$, and $Rg_1$)] under the concentration of $10^3$~$10^6$% on these enzymes In hepatocytes were also investigated, when they were added to these two media. The results were as follows. The specific activity of enzymes such as glucokinase, glucose 6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase related to glucose-consuming pathways of insulin-deficient group was much less than control one, however, their decreased activity was recovered after the addition of ginseng components at all range of concentrations. The increased specific activity of these on - zymes was shown by the addition of ginseng components to the control group. On the other hand, the specific activity of glucose 6-phosphatase related to glucose-producing pathway of insulin-deficient group was much higher than control one, but their Increased activity was decreased after the addition of ginseng components at all range of concentrations. The same results were obtained after the addition of ginseng components to the control group. These results suggest that the red ginseng saponin components might better diabetic hyperglycemia by regulating the activity of enzymes related to glucose metabolism directly and/or Indirectly though more detailed studies were needed.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.402-406
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• 1988

The aim of the presented paper was to elucidate the physiological background of ethanol inhibition on glucose uptake, ethanol production and cell growth in Z. mobilis. Data obtained from batch and continuous cultures showed that the rates of glucose uptake and ethanol production were not affected but growth rate was apparently reduced by ethanol produced. In order to know the effects of ethanol on the anabolism and the catabolism in Z. mobilis, enzyme activities of the Enter-Doudoroff pathway, viz. hexokinase, glucose 6-phosphate dehydrogenase, were analyzed with the cell grown at different concentration of ethanol produced. As results, it was found that the activities of the glucose kinase and the glucose 6-phosphate dehydrogenase were not affected greatly by the concentration of ethanol where the glucose uptake rates revealed a relatively constant value. However it was very interesting to note that transketolase, which is an essential enzyme to provide the important precursors for cell growth, was affected more apparently to reduce by increasing ethanol levels. Those results might suggest that the apparent reduction of growth rate at ethanol concentration above 20 g/$\ell$ would be caused by the reduction of the transketolase activity, which in turn provide less precursor for the cell growth.