• Journal of Microbiology
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• v.45 no.4
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• pp.318-325
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• 2007

Glucose 6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) in Deinococcus radiophilus, an extraordinarily UV-resistant bacterium, was investigated to gain insight into its resistance as it was shown to be involved in a scavenging system of superoxide $(O_2^{-1})$ and peroxide $(O_2^{-2})$ generated by UV and oxidative stresses. D. radiophilus possesses two G6PDH isoforms: G6PDH-1 and G6PDH-2, both showing dual coenzyme specificity for NAD and NADP. Both enzymes were detected throughout the growth phase; however, the substantial increase in G6PDH-1 observed at stationary phase or as the results of external oxidative stress indicates that this enzyme is inducible under stressful environmental conditions. The G6PDH-1 and G6PDH-2 were purified 122- and 44-fold (using NADP as cofactor), respectively. The purified G6PDH-1 and G6PDH-2 had the specific activity of 2,890 and 1,033 U/mg protein (using NADP as cofactor) and 3,078 and 1,076 U/mg protein (using NAD as cofactor), respectively. The isoforms also evidenced distinct structures; G6PDH-1 was a tetramer of 35 kDa subunits, whereas G6PDH-2 was a dimer of 60kDa subunits. The pIs of G6PDH-1 and G6PDH-2 were 6.4 and 5.7, respectively. Both G6PDH-1 and G6PDH-2 were inhibited by both ATP and oleic acid, but G6PDH-1 was found to be more susceptible to oleic acid than G6PDH-2. The profound inhibition of both enzymes by ${\beta}-naphthoquinone-4-sulfonic$ acid suggests the involvement of lysine at their active sites. $Cu^{2+}$ was a potent inhibitor to G6PDH-2, but a lesser degree to G6PDH-1. Both G6PDH-1 and G6PDH-2 showed an optimum activity at pH 8.0 and $30^{\circ}C$.

• Journal of Microbiology
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• v.40 no.1
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• pp.43-50
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• 2002

A cluster of genes encoding the pyruvate dehydrogenase complex (PDC) of Streptomyces seoulensis, a Gram-positive bacterium, was cloned and sequenced. The genes of S. seoulensis consist of four open reading frames. The first gene, lpd, which encodes a lipoamide dehydrogenase, is followed by pdhB encoding a dihydrolipoamide acetyltransferase (E2p), pdhR, a regulatory gene, and pdhA encoding a pyruvate dehydrogenase component (Elp). Elp had an unusual homodimeric subunit, which has been known only in Gram-negative bacteria S. seoulensis E2p contains two lipoyl domains like those of humans and Streptomyces faecalis. The pdhR gene appears to be clustered with the structural genes of S. seoulensis PDC. The PdhR-overexpressed S. seoulensis howed growth retardation and the decrease of Elp, indicating that PdhR regulates the function of PDC by repressing the expression of Elp. A strain of Streptomyces licidans overexpressing S. seoulensis PdhR showed a significant decreasein the level of actinorhodin, implying a regulatory role for Streptomyces PDC in antibiotic biosynthesis.

• 한국체육학회지인문사회과학편
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• v.55 no.3
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• pp.649-658
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• 2016

This study aimed to analyze PDH(Pyruvate dehydrogenase) and protein expression of PDK4(Pyruvate dehydrogenase kinase 4), PDP1(PDH phosphatase 1), enzymes that are involved in the activation of PDH, in skeletal muscle and to investigate the concentration of thiamine administration in liver and muscle following 4 weeks of endurance training. Methods : 6 weeks old male ICR mice were divided into two groups: sedentary group (CON, n=10; TH, n=10), and exercise group (EX, n=10, THEX, n=10). Thiamine(thiamine tetrahydrofurfuryl disulfide: TTFD) TTFD was orally administrated into TH and THEX groups in 50mg/kg body weight for 4 weeks. Treadmill training was performed in EX and THEX groups at about 70% of VO2max for 5 times a week for 4 weeks. Results : In this study, the concentration of glycogen was significantly increased following 4 weeks of endurance training, but a significant difference was not found following thiamine administration. Similarly, there was a significant effect of the training on PDH and the expression of PDK4 and PDP1 as PDH was increased by about 40% along with the increase in PDK4 and PDP1. However, there was no significant difference found between the groups following thiamine administration. Discussion : This result shows that there was no synergistic effect of thiamine administration, potentially due to adaptation of skeletal muscle from a long-term endurance training. Therefore, it will be necessary to consider the intake timing of thiamine and to analyze proteins that are related to PDH following the administration of complex carbohydrates.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.536-545
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• 2019

Cytochrome P450 (P450 or CYP) is involved in the metabolism of endogenous and exogenous compounds in most organisms. P450s have great potential as biocatalysts in the pharmaceutical and fine chemical industries because they catalyze diverse oxidative reactions using a wide range of substrates. The high-cost nicotinamide cofactor, NADPH, is essential for P450 reactions. Glucose-6-phosphate dehydrogenase (G6PDH) has been commonly used in NADPH-generating systems (NGSs) to provide NADPH for P450 reactions. Currently, only two G6PDHs from Leuconostoc mesenteroides and Saccharomyces cerevisiae can be obtained commercially. To supply high-cost G6PDH cost-effectively, we cloned the cytosolic G6PDH gene of Solanum lycopersicum (tomato) with 6xHis tag, expressed it in Escherichia coli, and purified the recombinant G6PDH (His-G6PDH) using affinity chromatography. In addition, enzymatic properties of His-G6PDH were investigated, and the His-G6PDH-coupled NGS was optimized for P450 reactions. His-G6PDH supported CYP102A1-catalyzed hydroxylation of omeprazole and testosterone by NADPH generation. This result suggests that tomato His-G6PDH could be a cost-effective enzyme source for NGSs for P450-catalyzed reactions as well as other NADPH-requiring reactions.

• 월간 기계설비
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• s.305
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• pp.78-86
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• 2015

프로필렌은 에틸렌과 함께 자동차부품, 수지, 섬유 등 석유화학 제품의 기초 원료로 사용되는 불포화 탄화수소 화합물의 일종이며 보통 석유 정제과정의 부산물로 생산된다. 그러나 최근들어 급증하는 프로필렌 수요 충족을 위해 프로판을 원료로 하는 프로필렌 생산기술(PDH)이 크게 주목받고 있다. 이에 따라 프로필렌 전용 생산공장으로는 세계 최대 규모인 SK어드밴스드 PDH(Propane Dehydroganation) Plant가 울산시 남구 신항만 근처 약 10만$4,000m^2$ 부지에 건설되고 있다. 울산 PDH 현장은 지난 2014년 6월 1일 시공에 들어가 오는 2016년 3월 31일 완공될 예정이다. 완공 후 정상가동에 들어가면 70만t의 LPG를 원료로 연간 약 60만t의 프로필렌을 생산하게 된다. 본지는 기계적 완성(MC, Mechanical Completion)을 달성하고 테스트 작업이 한창인 울산 PDH Plant 현장에서 P1 Area의 기계설비, 배관 및 철골공사를 담당하고 있는 (주)동부(대표 김재홍)의 변유진 현장소장을 만났다.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.84-87
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• 2006

Batch binding experiments were performed to assess the recovery performance of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) bound to the unshielded and polymer (polyvinyl pyrrolidone. PVP)-shielded dye-ligand (Cibacron Blue 3GA) adsorbent. The adoption of a polymer-shielded, dye-ligand technique facilitated the elution efficiency of bound G3PDH. It was demonstrated that the recovery of G3PDH using polymer-shielded dye-ligand adsorption yielded higher elution efficiency, at 60.5% and a specific activity of 42.3 IU/mg, after a low ionic strength elution (0.15 M NaCl). The unshielded dye-ligand yielded lower elution efficiency. at 6.5% and a specific activity of 10.2 IU/mg.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1531-1535
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• 2005

The present study was designed to investigate the antidiabetic effect of Cordyceps militaris on activities of hepatic glucose-regulating enzymes, such as glucokinase (GK), pyruvate dehydrogenase (PDH) and acetyI-CoA carboxylase (ACC). We have isolated the active compounds, CM-A and CM-B from C. militaris and the extracts are under investigation to determine their mechanism of action. Hepatic GK, PDH and ACC activities were significantly (p < 0.05) increased compared with the control. Treatment with CM-A led to a rise in percentage of enzymes by 380$\%$,396$\%$ and 286$\%$, respectively, relative to control levels. CM-B were 329$\%$, 312$\%$ and 239$\%$, respectively. The increase in GK and ACC activities was linearly proportional with increased ratio of CM-A. Our findings suggest that C. militaris exerted antihyperglycemic potency, which is thought to be mediated through activation of GK, PDH and ACC enzymes related to glucose metabolism directly or indirectly and therefore C. militaris is promising as antidiabetic functional foods.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.197-201
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• 2004

A 2-D gel protein analysis of Lactobacillus reuteri ATCC 55739 produced spots corresponding to subunits of the pyruvate dehydrogenase complex, as identified by N-terminal protein sequencing. Oligonucleotide probes specific for the subunits of the pyruvate dehydrogenase complex were synthesized ,md used to screen a L. reuteri genomic library to clone the structural genes. Two positive clones were isolated and identified as having the same 2.2 kb insert. A pdhB encoding the $\beta$-subunit of El subunit (pyruvate dehydrogenase component) of the pyruvate dehydrogenase complex was located in the middle of the insert. Furthermore, a 5' truncated pdhA encoding the $\alpha$-subunit of the E1 subunit and a 3' truncated pdhC encoding the E2 subunit (dihydrolipoamide acetyltransferase) were also located upstream and downstream of the pdhB, respectively.

• Journal of Veterinary Clinics
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• v.19 no.4
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• pp.455-460
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• 2002

Pituitary-dependent hyperadrenocorticism (PDH) was diagnosed with history taking, physical examination, complete blood count, serum chemistry profiles, abdominal radiology, ultrasonography and adrenal function tests in 3 dogs. Their clinical signs were polyuria, polydipsia, polyphagia, bilateral symmetrical truncal alopecia and secondary infection in skin or urinary tract. Especially one dog showed severe clinical signs such as calcinosis cutis and delayed wound healing. These 3 dogs were diagnosed as PDH, and treated with selegiline 1-2 mg/kg /ay sid PO. 2 dogs with clinical signs of PDH were disappeared and improved, but 1 dog with severe illness progressed gradually despite of selegiline and mitotane application, and eventually died.

• 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.