• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.39-45
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• 2002

Activity staining on the native polyacrylamide gel electrophoresis (PAGE) of a cell-free extract of Rhodococcus sp. TK6, grown in media containing alcohols as the carbon source, revealed at least seven isozyme bands, which were identified as alcohol dehydrogenases that oxidize cyclohexanol to cyclohexanone. Among the alcohol dehydrogenases, cyclohexanol dehydrogenase II (CDH II), which is the major enzyme involved in the oxidation of cyclohexanol, was purified to homogeneity. The molecular mass of the CDH II was determined to be 60 kDa by gel filtration, while the molecular mass of each subunit was estimated to be 28 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The CDH II was unstable in acidic and basic pHs, and rapidly inactivated at temperatures above $40^{\circ}C$ . The CDH II activity was enhanced by the addition of divalent metal ions, like $Ba^2+\;and\;Mg^{2+}$. The purified enzyme catalyzed the oxidation of a broad range of alcohols, including cyclohexanol, trans-cyclohexane-1,2-diol, trans-cyclopentane-l,2-diol, cyclopentanol, and hexane-1,2-diol. The $K_m$ values of the CDH II for cyclohexanol, trans-cyclohexane-l,2-diol, cyclopentanol, trans-cyclopentane-l,2-diol, and hexane-l,2-diol were 1.7, 2.8, 14.2, 13.7, and 13.5 mM, respectively. The CDH II would appear to be a major alcohol dehydrogenase for the oxidation of cyclohexanol. The N-terminal sequence of the CDH II was determined to be TVAHVTGAARGIGRA. Furthermore, based on a comparison of the determined sequence with other short chain alcohol dehydrogenases, the purified CDH II was suggested to be a new enzyme.

• BMB Reports
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• 제42권10호
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• pp.673-678
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• 2009

The cDNA of alcohol dehydrogenase (PgADH) was isolated and characterized from the leaf of Panax ginseng. The cDNA had an open reading frame of 801 bp and a deduced amino acid sequence of 266 residues. The calculated molecular mass of the mature protein is approximately 29 kDa with a predicated isoelectric point of 6.84. Homology analysis revealed that the deduced amino acid of PgADH shares a high degree of homology with the short-chain ADH proteins of other plants. Genomic DNA hybridization analysis indicated that PgADH represents a multi-gene family. The expression of PgADH under various environmental stresses was analyzed at different time points using real-time PCR. ABA, SA and especially JA (80-fold) significantly induced PgADH expression within 24 h of treatment. The positive responses of PgADH to abiotic stimuli suggest that ginseng ADH may protect against hormone-related environmental stresses.

• 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.