• 환경생물
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• 제20권2호
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• pp.173-179
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• 2002

N-nitrosoethylurea(NEU)에 의한 지질 과산화물의 함량 변화와 알데히드 대사효소 및 항산화효소의 활성변화를 쥐 간세포에서 측정하였다. 알데히드 대사효소로는 alcohol dehydrogenase와 aldehyde dehydrogenase가 사용되었고 항산화효소로는 glutathione transferase, superoxide dismutase, glutathione reductase와 catalase가 사용되었다. 쥐 간세포에 다양한 농도의 NEU를 처리한 후 지질 과산화물의 함량변화를 측정하였다. 그 결과 6.25mM NEU에 의하여 지질 과산화물의 함량이 최대 2.5배 증가하였다. Alcohol dehydrogenase의 활성은 NEU처리에 의하여 대조군보다 최대 2.3배 증가하였고 aldehyde dehydrogenase의 활성은 약 2배 증가하였다. 전암성 병변의 지표로 이용되는 glutathione transferase와 catalase의 경우 NEU처리에 의한 활성증가가 미미하였다. 그러나 superoxide dismutase의 활성은 최대 1.5배 증가하였고, glutathione reductase의 활성은 약 3배 증가하였다. 그러므로 superoxide dismutase와 g1utathione reductase의 활성증가가 NEU의 독성에 대한 세포내 항산화 방어과정에서 중요한 역할을 할 것으로 추측된다

• 생명과학회지
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• 제16권3호
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• pp.375-381
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• 2006

Saccharomyces cerevisiae 로부터 알데히드 환원효소를 정제하였다. 정제된 알데히드 환원효소를 biocatalyst로 사용하여 치환기가 있는 카르보닐 화합물의 선택적 환원을 시도하였다. 효소를 이용한 환원반응의 생성물의 구조를 TLC, GC, Mass, NMR, FT-IR을 이용하여 확인하였으며 효소를 이용한 환원반응이 높은 선택성을 가지고 진행됨을 확인하였다. 또한 이 반응은 알데히드 환원효소의 억제제인 벤조산에 의해 크게 억제되었다. 치환기가 있는 카르보닐 화합물의 선택적 환원반응은 의약품 제조 분야에서 매우 중요한 반응이며 미생물에서 정제한 알데히드 환원효소가 biocatalyst 로서 선택적 환원반응에 이용될 수 있으리라 사료된다.

• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1699-1707
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• 2013

During the fermentative production of 1,3-propanediol under high substrate concentrations, accumulation of intracellular 3-hydroxypropionaldehyde will cause premature cessation of cell growth and glycerol consumption. Discovery of oxidoreductases that can convert 3-hydroxypropionaldehyde to 1,3-propanediol using NADPH as cofactor could serve as a solution to this problem. In this paper, the yqhD gene from Klebsiella pneumoniae DSM2026, which was found encoding an aldehyde reductase (KpAR), was cloned and characterized. KpAR showed broad substrate specificity under physiological direction, whereas no catalytic activity was detected in the oxidation direction, and both NADPH and NADH can be utilized as cofactors. The cofactor binding mechanism was then investigated employing homology modeling and molecular dynamics simulations. Hydrogen-bond analysis showed that the hydrogen-bond interactions between KpAR and NADPH are much stronger than that for NADH. Free-energy decomposition dedicated that residues Gly37 to Val41 contribute most to the cofactor preference through polar interactions. In conclusion, this work provides a novel aldehyde reductase that has potential applications in the development of novel genetically engineered strains in the 1,3-propanediol industry, and gives a better understanding of the mechanisms involved in cofactor binding.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2002년도 제37회 국제학술심포지움 및 추계학술대회
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• pp.74-74
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• 2002

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.162-162
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• 2008

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.72-72
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• 1995

Monoclonal antibodies against bovine brain succinic semialdehyde reductase were produced and characterized. A total of nine monoclonal antibodies recognizing different epitopes of the enzyme were obtained, of which two inhibited the enzyme activity and three stained cytosol of rat spinal cord neurons as observed by indirect immunofluorescence microscopy. When unfractionated total proteins of bovine brain homogenate were seperated by gel electrophoresis and immunoblotted, the antibodies specifically recognized a single protein band of 34 kDa, which comigrates with purified bovine succinic semialdehyde reducatase Using the antisuccinic semialdehyde reductase antibodies as probes, we investigated the cross-reactivites of brain succinic semialdehyde reductases from some mammalian and an avian species. The immunoreactive bands on Western blots appeared to be the same in molecular mass-34 kDa-in all animal species tested, including humans. The result indicated that brain succinic semialdehyde reductase is distinct from other aldehyde reductases and that mammalian brains contain only one succinic semialdehyde reductase. Moreover, the enzymes among the species are imunologically very similar, although some properties of the enzymes reported previously were different from one another.

• Journal of Plant Biotechnology
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• 제1권1호
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• pp.61-68
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• 1999

Rapid accumulation of reactive oxygen species (ROS) and their toxic reaction products with lipids and proteins significantly contributes to the damage of crop plants under biotic and abiotic stresses. We have identified several stress activated alfalfa genes, including the gene of the alfalfa ferritin and a novel NADPH-dependent aldose/aldehyde reductase enzyme. Transgenic tobacco plants that synthesize alfalfa ferritin in vegetative tissues-either in its processed form in chloroplast or in the cytoplasmic non-processed form-retained photosynthetic function upon free radical toxicity generated by paraquat treatment and exhibited tolerance to necrotic damage caused by viral and fungal infections. We propose that by sequestering intracellular iron involved in generation of the very reactive hydroxyl radicals through a Fenton reaction, ferritin protects plant cells from oxidative damage. Our preliminary results with the other stress-inducable alfalfa gene (a NADPH-dependent aldo-keto reductase) indicate, that the encoded enzyme may play role in the stress response of the plant cells. These studies reveal new pathways in plants that can contribute to the increased stress resistance with a potential use in crop improvement.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.506-514
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• 2020

4-Hydroxybenzyl alcohol (4-HB alcohol)은 두통, 경련 행동, 현기증과 같은 신경계 질환에 유익한 효과를 나타내며 천마의 주요 생리활성 성분 중의 하나이다. 대사공학을 통해 4-hydroxybenzoate (4-HBA)를 생산하는 균주로부터 4-HB alcohol을 생산하는 재조합 Corynebacterium glutamicum을 개발하였다. 먼저 4-HBA를 생산하는 APS809로부터 염색체 내 NCgl2922 유전자에 Methanocaldococcus jannaschii 유래의 aroK 유전자를 삽입한 APS963을 개발하였다. 4-HBA의 카로복실 산을 4-hydroxybenzaldehyde (4-HB aldehyde)로의 환원을 촉매하는 Nocardia iowensis 유래의 car 유전자를 염색체에서 발현하는 균주를 개발하기 위해 NCgl1112 유전자 일부 단편에 car 유전자가 삽입된 GAS177를 개발하였다. 더 높은 농도의 4-HB alcohol을 생산하기 위해 4-HB alcohol을 aldehyde로 산화를 촉매하는데 관여하는 creG 유전자를 염색체상에서 제거된 GAS255를 개발하였다. 최종적으로 chorismate를 4-HBA로 전환하는 효소의 유전자 ubiCpr을 pcaHG에 삽입된 GAS355를 개발하였으며, 80 g/l 포도당을 함유한 삼각플라스크에서 발효하여 생산성을 평가한 결과, 2.3 g/l 4-HB alcohol이 생산되었으며 부산물로 0.32 g/l 4-HBA, 0.3 g/l 4-HB aldehyde가 축적되었다.

• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.271-278
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• 2001

Oxidative stress and methylglyoxal (MG), a reactive dicarbonyl metabolites produced by enzymatic and non-enzymatic reaction of normal metabolism, induced aldose reductase (AR) expression in rat aortic smooth muscle cells (SMC). AR expression was induced in a time-dependent manner and reached at a maximum of 4.5-fold in 12 h of MG treatment. This effect of MG was completely abolished by cyclohemide and actinomycin D treatment suggesting AR was synthesized by de novo pathway. Pretreatment of the SMC with N-acetyl-L-cysteine significantly down-regulated the MG-induced AR mRNA. Furthermore, DL-Buthionine-(S,R)-sulfoximine, a reagent which depletes intracellular glutathione levels, increased the levels of MG-induced AR mRNA. These results indicated that MG induces AR mRNA by increasing the intracellular peroxide levels. Aminoguanidine, a scanvenger of dicarbonyl, significantly down-regulated the MG-induced AR mRNA. In addition, the inhibition of AR activities with statil, an AR inhibitor, enhanced the cytotoxic effect of MG on SMC under normal glucose, suggesting a protective role of AR against MG-induced cell damages. These results imply that the induction of AR by MG may contribute to an important cellular detoxification of reactive aldehyde compounds generated under oxidative stress in extrahepatic tissues.

• BMB Reports
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• 제32권3호
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• pp.254-258
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• 1999

The NADPH-dependent succinic semialdehyde reductase is one of the key enzymes in the brain GABA shunt, and it catalyzes the formation of the neuromodulator $\gamma$-hydroxybutyrate from succinic semi aldehyde. This enzyme was inactivated by diethylpyrocarbonate (DEP) with the second-order rate constant of $1.1{\times}10^3\;M^{-1}min^{-1}$ at pH 7.0, $25^{\circ}C$, showing a concomitant increase in absorbance at 242 nm due to the formation of N-carbethoxyhistidyl derivatives. Complete inactivation of succinic semialdehyde reductase required the modification of five histidyl residues per molecule of enzyme. However, only one residue was calculated to be essential for enzyme activity by a statistical analysis of the residual enzyme activity. The inactivation of the enzyme by DEP was prevented by preincubation of the enzyme with the coenzyme NADPH but not with the substrate succinic semialdehyde. These results suggest that an essential histidyl residue involved in the catalytic activity is located at or near the coenzyme binding site of the brain succinic semialdehyde reductase.