• Journal of Microbiology and Biotechnology
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• 제4권4호
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• pp.360-363
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• 1994

A colorimetric assay for $\gamma$-glutamyl transpeptidase ($\gamma$-CTP; E.C 2.3.2.2) employing 2, 4, 6-trinitrobenzene sulfonate (TNBS) to detect the amount of disappeared acceptor via transpeptidation, has been developed. Under the experimental conditions using L-$\gamma$-glutamyl ethyl ester and L-phenylalanine as $\gamma$-glutamyl donor and acceptor, respectively, it was found that the decreased absorbance of yellow color at 420 nm was strictly related to the amount of L-$\gamma$-glutamyl-L-phenylalanine (L-$\gamma$-Glu-L-Phe) formed, which was determined by DEAE-cellu-lose column chromatography. Concentrations of the enzyme and $\gamma$-glutamyl products were able to be determinedin the nanogram and nanomoles per milliliter range, respectively, with high precision and reliability. This novel assay system may therefore be a useful means for understanding of catalytic function of the $\gamma$-CTP spectrophotometrically without any usage of sophisticated instruments.

• 생명과학회지
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• 제13권5호
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• pp.626-633
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• 2003

백서에 bromate의 장기간 섭취로 간 및 신장의 glutathion량이 감소되는데, 간과 신장은 유사한 감소양상을 나타냈고, 폐 및 혈액에서는 감소하는 경향은 있었으나 통계적인 유의성은 없었다. Bromate 섭취로$\gamma-glutamyl$-cysteine synthetase와 $\gamma-glutamyl$ transpeptidase 활성이 감소되었다. 따라서 간과 신장의 glutathione 감소로 $\gamma-glutamyl$cysteine synthetase 활성이 감소됨으로서 glutathione 합성저하에 의해 나타난 결과로 생각되고, 폐에서 $\gamma-glutamyl$cysteine synthetase 및 $\gamma-glutamyl$- transpep-tidase 활성에는 별다른 영향이 없었다. 혈액에서는$\gamma-glutamyl$cysteine synthetase와 $\gamma-glutamyl$ transpeptidase 활성 감소로 glutathione의 혈액내로 유입과 타장기로 유출이 모두 저하되어 glutathione량의 변화가 없는 것으로 생각된다. Bromate에 의한 장기내 glutathione량 감소는 유리기 소거기능이 저하되어 bromate에 의해서 생성된 유리기 제거가 미흡할 것으로 생각되므로 bromate 독성의 한 요인이 될 것으로 추측된다.

• 한국식품과학회지
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• 제43권5호
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• pp.553-557
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• 2011

마늘의 천연 성분을 분석하였을 때 8개의 주요 성분이 나타났으며, 가장 크게 나타난 피크는 알린이었고 실제로 함량도 가장 높게 나타났다. 이소알린은 알린의 뒤를 이어 큰 피크를 나타내었고 함량도 알린에 이어 많은 양이 얻어졌다. 기타 마늘 특유의 함황유기화합물로서 ${\gamma}$-glutamyl peptide류가 있으며 함량이 충분하여 분리 정제를 수행한 것으로는 ${\gamma}$-glutamyl-S-allylcysteine, ${\gamma}$-glutamyl-S-1-propenylcysteine, ${\gamma}$-glutamylphenylalanine 등 3가지였다. 기타 마늘 특유의 성분은 아니지만 UV 208 nm에서 흡광도를 크게 나타내는 것으로 arginine, tyrosine, phenylalanine, tryptophan과 같은 일반적인 아미노산류가 있었지만, 본 연구에서는 마늘 특유의 아미노산과 펩타이드만을 정제하였다. 마늘 특이 아미노산과 펩타이드의 분리정제는 재순환 분취 HPLC를 이용하여 순수하게 정제하였으며, 생마늘 6 kg으로부터 알린, 이소알린, ${\gamma}$-glutamyl-S-allylcysteine, ${\gamma}$-glutamyl-S-1-propenylcysteine, ${\gamma}$-glutamylphenylalanine이 각각 7.32, 1.53, 0.38, 0.42, 0.23 g을 얻었으며 이를 마늘 함유량 대비 수율로 계산하면 각각 12.2, 42.5, 1.6, 1.2, 4.8%이었다. 정제한 물질들의 동정방법은 HPLC 머무름 시간의 비교 및 LC/MS를 이용한 분자량 측정이었다. 동일한 분자량을 가지는 알린과 이소알린을 분별하기 위해 $^1H$-NMR를 그리고 ${\gamma}$-glutamyl-S-allylcysteine과 ${\gamma}$-glutamyl-S-1-propenylcysteine을 구별하기 위해 $^1H$-NMR과 $^{13}C$-NMR분석을 수행하였다.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.238-244
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• 1996

$\gamma$-Glutamyl transpeptidase ($\gamma$-GTP; EC 2.3.2.2) present in the culture filtrate of Bacillus sp. KUN-17 was purified 400-fold through a consecutive procedure including organic precipitation and column chromatography. The enzyme has an estimated molecular weight of 70, 000 and consists of hetero-subunits with molecular weights of 42, 000 and 22, 000. In vitro optimal conditions for those transfer and hydrolysis reactions appeared to be pH 7.0 at $50^{\circ}C$ and pH 8.4 at $40^{\circ}C$, respectively. The denatured enzyme recovered most of its $\gamma$-GTP activity by removing detergents such as sodium dodecyl sulfate (SDS) or urea with dialysis. The enzyme showed higher affinities against a number of amino acids as $\gamma$-glutamyl acceptors than glycylglycine in the following order: L-valine, L-methionine, L-glutamic acid or L-as-paragine, L-alanine. Also, it was shown that L-glutamine was the most suitable $\gamma$-glutamyl donor for the transfer reaction among those tested. Amino acids generally inhibited the enzyme activity for the transfer reaction, but not for the hydrolysis reaction.

• 환경위생공학
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• 제19권1호
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• pp.50-56
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• 2004

Dibutyl phthalate (DBP) is used extensively in the plastic industry and has been known as an endocrine disruptor. Present study was undertaken to examine whether DBP can induce oxidative stress in mice. In this study, oxidative stress was measured in terms of the modification of lipid peroxidation and gamma-glutamyl transferase (GGT) activity. The serum toxicity index, level of lipid peroxidation and triglyceride (TG), and activity of GGT were measured in male ICR mice after a single administration of DBP (5 g/kg, po). DBP did not alter serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, glucose and cholesterol level. However, the treatment with DBP was found to significantly increase the level of lipid peroxidation in liver and lung. The TG content and activity of GGT in the liver of DBP-exposed animals was also increased. These results indicate that DBP can induce mild oxidative stress in mice. The GGT activity is considered to be increased as one of the adaptive defense mechanisms to oxidative stress induced by DBP.

• Journal of Periodontal and Implant Science
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• 제23권3호
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• pp.517-525
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• 1993

Glutathione(GSH),a tripeptide thiol, found in virtually all cells, functions in metabolism tranasport and cellular protection. It protects cells against the destructive effects of reactive oxygen intermediates and free radicals. Also ${\gamma}-Glutamyl$ transpeptidase(${\gamma}-GTT$), an enzyme of major importance in GSH metabolism, initiates GSH degradation. In order to explore the $GSH-{\gamma}-GTT$ system as periodontal disease activity indicator, we observed the ${\gamma}-GTT$ and arachidonic acid metabolits according to clinical groups(Control, Adult periodontitis, Rapidly progressive Periodontitis). From the experiments, the following results were obtained. 1. When compared with normal, ${\gamma}-GTT$ of A. P. and R. P. P. were increased, and only the change of ${\gamma}-GTT$ of R. P. P. was statistically significant(P<0. 05). 2. The amounts of arachidonic acid metabolites were not different with statistical significance among the clinical groups. 3. ${\gamma}-GTT$ may by useful adjuncts as new cytoprotective indicator and periodontal disease activity indicator in accordance with positive corelation pocket depth, attachment level and ${\gamma}-GTT$.

• 융합정보논문지
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• 제10권12호
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• pp.146-155
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• 2020

본 연구는 대사증후군을 예측하는 대리 표지자로서 감마 글루타밀 전이효소(gamma glutamyl transferase, GGT)의 유용성을 평가하고자 하였다. 20세 이상의 비만하지 않은 남성 7,155명을 연구대상자로 하였다. 대사증후군 진단기준은 NCEP-ATP III (National Cholesterol Education Program - Third Adult Treatment Panel) 기준을 적용하였다. GGT에 따른 대사증후군 발병 위험도는 로지스틱 회귀분석을 적용하였으며, GGT의 대사증후군 위험 예측능력을 확인하기 위해 ROC (receiver operating characteristic) 곡선을 구하였다. 연령과 체질량지수와 무관하게 GGT 1사분위수보다 4사분위수에서 대사증후군 발병위험이 7.09배 높게 나타났다(p<0.001). 대사증후군 진단을 위한 GGT의 곡선아래면적(area under the curve)은 0.715였으며, GGT의 절단값(cut-off value)은 40.0 U/L, 민감도는 65.0%, 특이도 70.2%로 나타났다. 따라서 GGT는 대사증후군을 진단하기 위한 유용한 진단 지표로 판단된다.

• Applied Biological Chemistry
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• 제36권3호
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• pp.184-190
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• 1993

Rhodobacter sphaeroides 균주가 생산하는 ${\delta}-aminolevulinic\;acid(ALA)$의 생산성에 관하여 in vivo, in vitro 상에서 기질 및 관련 화합물을 이용하여 검토하였다. $C_5\;ALA$ 생합성계에 의한 ALA yield 대비의 $C_4$ 생합성계에 의한 비율은 in vive 상에서 0.78인 반면, in vitro 상에서의 비율은 1.37이었다.$C_4\;C_5$ 각 계의 기질 첨가 배양에 의한 cell-free system의 $C_4,\;C_5$ 계의 발현도는 미첨가 배양에 의한 system과 비교하여 각각 1.35, 1.52로 증가하였으나, 증가한 계에 대한 상대계의 발현도가 억제되어, $C_4$ 와 $C_5$ 계가 각각 0.91, 0.83으로 나타났다. ${\gamma}-Glutamyl\;derivatives$의 세포내 uptake rates는 L-glutamic acid를 기준으로 비교해서 D-glutamic acid, 0.55: D-glutamine, 0.5: L-glutamine, 0.4: ${\gamma}-L-glutamyl\;ethylester$, 0.3: GSH 및 Glu-pNA, 0의 순서를 보였다. Uptake rate와 관계없이 in vivo 상에서 L-과 D-glutamine이 L-, D-glutamic acid보다 균체 외 ALA의 생산에 있어서 각각 높은 yield의 효과를 보였다.

• 대한화학회지
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• 제5권1호
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• pp.15-17
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• 1961

A ninhydrin positive substance(formed during germination of Mung Bean) which on a 2-dimensional chromatography(BuOH-HAc, and$ PhOH-NH_2$ gave a spot above glutamic acid was isolated by cutting out the appropriate spot on the paper and extracting the paper with water. Hydrolysis of this substance with $2N H_2SO_4\;or\;3N\;HCl\;at\;120^{\circ}C$ for 15 hours gave the spot of mainly glutamic acid, alanine and very faint of glycine and cysteine on a paper chromatography. It is suggested that the reaction of ${\gamma}$-glutamyl-cysteinecyl-glycine + L-alanine in the presence of ${\gamma}$-glutamyle transferase ${\rightarrow}$ ${\gamma}$-glutamyl-alanine + cysteinyl-glycine, takes place in germinated Mung Bean.

• Bulletin of the Korean Chemical Society
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• 제1권3호
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• pp.101-104
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• 1980

A sequential copolypeptide with repeating unit sequences, in which a glycyl residue is flanked progressively by two ${\gamma}$-benzyl-L-glutamyl residues, has been synthesized by poymerizing p-nitrophenyl ester of ${\gamma}$-benzyl-L-glutamyl-${\gamma}$ -benzyl-L-gutamyl-glycine. Polymers obtained were characterized by viscosity and infra-red spectral data. The highest molecular weight obtained was 21,000. Molecular conformation in solid state was found to be a mixed form of and |${\beta}$-structure. Polymers obtained were insoluble in the most of the organic solvents except in a strong acid like dichloroacetic acid, but in binary mixtures of solvents such as dichloroacetic acid-ethylene dichloride or dichloroacetic acid-chloroform, they were soluble within certain ranges of solvent compositions.