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J A Duine - One of the best experts on this subject based on the ideXlab platform.

  • nicotinoprotein alcohol Aldehyde Oxidoreductases
    1996
    Co-Authors: Sander R Piersma, Simon De Vries, J A Duine
    Abstract:

    Enzymes with tightly bound NAD(P), acting as cofactor, have been described in the past. Well known examples include UDP-galactose 4-epimerase from E. coli (Wilson and Hogness, 1964) and lactate-oxaloacetate transhydrogenase from V. alcalescens (Allen, 1966). Recently enzymes have been discovered in which the bound NAD(P) acts as cofactor in the oxidation/reduction of alcohols/Aldehydes and the reducing equivalents do not exchange with the cytosolic NAD(P) pool but are probably transferred to the respiratory chain (Arfman, 1991, Bystrykh, 1993, van Ophem, 1993). These enzymes operate in the same way as, e.g., flavoprotein or quinoprotein alcohol dehydrogenases and are clearly distinct from the NAD(P)(H) dependent alcohol/Aldehyde Oxidoreductases in a physiological sense. In the latter case nicotinamide pyridine dinucleotide acts as coenzyme (i.e. as co-substrate) and forms part of the cytosolic NAD(H) pool. We have introduced the name nicotinoproteins for this new group of NAD(P)(H) containing enzymes (van Ophem, 1993). Nicotinoproteins are proteins which contain NAD(P)(H) as tightly bound, redox active cofactor. The pyridine dinucleotide in these enzymes is strongly but not covalently bound and does not exchange with the cytosolic NAD(P) pool. In Table 1 enzymological data of some of the nicotinoproteins known presently is summarised.

  • nicotinoprotein nad p containing alcohol Aldehyde Oxidoreductases purification and characterization of a novel type from amycolatopsis methanolica
    FEBS Journal, 1993
    Co-Authors: Peter W Van Ophem, Jozef Van Beeumen, J A Duine
    Abstract:

    Extracts of Gram-positive bacteria like Rhodococcus rhodochrous, Rhodococcus erythropolis and Amycolatopsis methanolica, but not those of several Gram-negative ones, showed dehydrogenase activity for ethanol as well as for methanol when 4-nitroso-N, N-dimethylaniline (NDMA) was used as electron acceptor. Chromatography of extracts of the first two organisms revealed one activity for both substrates, that of A. methanolica two activities, one of which is able to oxidize methanol and has been purified (Bystrykh, L. V., Govorukhina, N. I., van Ophem, P. W., Hektor, H. J., Dijkhuizen, L. and Duine, J. A., unpublished results). The other, indicated as NDMA-dependent alcohol dehydrogenase (NDMA-ADH), was purified to homogeneity. It is a trimeric enzyme consisting of subunits of 39 kDa and one firmly bound NAD as cofactor. Although NDMA-ADH shows structural similarity with the long-chain, zinc-containing, NAD(P)-dependent alcohol dehydrogenases with respect to the N-terminal sequence up to residue 41 (56% identity with horse liver alcohol dehydrogenase), the enzymes are catalytically different since NDMA-ADH is unable to use NAD(P)(H) as a coenzyme and NAD(P)-dependent alcohol dehydrogenases are inactive with NDMA (in the absence of NAD). Comparison of the NDMA-ADH properties with those of the methanol-oxidizing enzyme of A. methanolica, Mycobacterium gastri and Bacillus methanolica C1, and formAldehyde dismutase of Pseudomonas putida F61 revealed large differences in structural as well as catalytic properties, in spite of the fact that all are nicotinoproteins [enzymes which have bound NAD(P) as a cofactor]. It is concluded, therefore, that NDMA-ADH is a novel type of nicotinoprotein alcohol dehydrogenase.

  • microbial alcohol Aldehyde Oxidoreductases in enantioselective conversions
    1992
    Co-Authors: Arie Geerlof, J B A Van Tol, Jaap A Jongejan, J A Duine
    Abstract:

    Microbes have an enormous diversity of alcohol and Aldehyde Oxidoreductases. A brief overview is given of the types known and of some novel ones discovered recently. Except from the classical, NAD-dependent, alcohol dehydrogenase (the long chain, zinc-containing type, EC 1.1.1.1), these enzymes are unexplored with respect to enantioselectivity. The present paper shows that quinohaemoprotein ethanol dehydrogenases, enzymes containing PQQ and haem c as cofactors and occurring in bacteria having very efficient respiratory chains for ethanol oxidation (e.g. Acetic acid bacteria), are well suited for the kinetic resolution of racemic alcohols (the C3 -synthons glycidol and solketal). Methods are dicussed to measure reliable E-values (enantiomeric ratio) of the enzymes with respect to substrate and intermediates. For that purpose, methods based on initial rate kinetics and end point determinations as well as progression curve analysis were applied. Some preliminary results on the effect of cofactor engineering on enantioselectivity indicate that changes in negative as well as positive sense can be expected.

Belarmino A S Barata - One of the best experts on this subject based on the ideXlab platform.

  • Aldehyde Oxidoreductases and other molybdenum containing enzymes
    Methods in Enzymology, 1994
    Co-Authors: Jose J G Moura, Belarmino A S Barata
    Abstract:

    Publisher Summary This chapter describes Aldehyde Oxidoreductases and other molybdenum (Mo)-containing enzymes. Desulfovibrio gigas ( D. gigas ) Mo -containing protein is isolated on the basis of its optical absorption characteristics.Mo was first detected by electron paramagnetic resonance (EPR). All purification operations for Aldehyde Oxidoreductases are carried out at 4, starting from a D. gigas NCIB 9332 cell-free crude extract. Activity is determined aerobically at 25 by measuring the rate of 2, 6-dichlorophenol-indophenol (DCPIP) reduction at 600 nm ) in a 1-cm optical path spectrophotometer quartz cell. A pH profile of the enzyme activity is determined in different buffer systems, such as citrate, phosphate, Tris-HCl, and Tris-glycine—covering a pH range of 4–11. DCPIP and ferricyanide are shown to be capable of cycling the electronic flow, whereas other cation and anion dyes do not. The visible absorption spectrum of the protein is similar to that observed for the deflavo forms of xanthine and Aldehyde oxidases and reminiscent of the one observed for plant-type ferredoxins.

Jose J G Moura - One of the best experts on this subject based on the ideXlab platform.

  • Aldehyde Oxidoreductases and other molybdenum containing enzymes
    Methods in Enzymology, 1994
    Co-Authors: Jose J G Moura, Belarmino A S Barata
    Abstract:

    Publisher Summary This chapter describes Aldehyde Oxidoreductases and other molybdenum (Mo)-containing enzymes. Desulfovibrio gigas ( D. gigas ) Mo -containing protein is isolated on the basis of its optical absorption characteristics.Mo was first detected by electron paramagnetic resonance (EPR). All purification operations for Aldehyde Oxidoreductases are carried out at 4, starting from a D. gigas NCIB 9332 cell-free crude extract. Activity is determined aerobically at 25 by measuring the rate of 2, 6-dichlorophenol-indophenol (DCPIP) reduction at 600 nm ) in a 1-cm optical path spectrophotometer quartz cell. A pH profile of the enzyme activity is determined in different buffer systems, such as citrate, phosphate, Tris-HCl, and Tris-glycine—covering a pH range of 4–11. DCPIP and ferricyanide are shown to be capable of cycling the electronic flow, whereas other cation and anion dyes do not. The visible absorption spectrum of the protein is similar to that observed for the deflavo forms of xanthine and Aldehyde oxidases and reminiscent of the one observed for plant-type ferredoxins.

Jungoh Ahn - One of the best experts on this subject based on the ideXlab platform.

  • combinatorial application of two Aldehyde Oxidoreductases on isobutanol production in the presence of furfural
    Journal of Industrial Microbiology & Biotechnology, 2016
    Co-Authors: Hyung-min Seo, Jong-min Jeon, Ju Hee Lee, Hun-suk Song, Han-byul Joo, Sung-hee Park, Kwon-young Choi, Yong Hyun Kim, Kyungmoon Park, Jungoh Ahn
    Abstract:

    Furfural is a toxic by-product formulated from pretreatment processes of lignocellulosic biomass. In order to utilize the lignocellulosic biomass on isobutanol production, inhibitory effect of the furfural on isobutanol production was investigated and combinatorial application of two Oxidoreductases, FucO and YqhD, was suggested as an alternative strategy. Furfural decreased cell growth and isobutanol production when only YqhD or FucO was employed as an isobutyrAldehyde oxidoreductase. However, combinatorial overexpression of FucO and YqhD could overcome the inhibitory effect of furfural giving higher isobutanol production by 110 % compared with overexpression of YqhD. The combinatorial Oxidoreductases increased furfural detoxification rate 2.1-fold and also accelerated glucose consumption 1.4-fold. When it compares to another known system increasing furfural tolerance, membrane-bound transhydrogenase (pntAB), the combinatorial Aldehyde Oxidoreductases were better on cell growth and production. Thus, to control Oxidoreductases is important to produce isobutanol using furfural-containing biomass and the combinatorial overexpression of FucO and YqhD can be an alternative strategy.

Peter W Van Ophem - One of the best experts on this subject based on the ideXlab platform.

  • nicotinoprotein nad p containing alcohol Aldehyde Oxidoreductases purification and characterization of a novel type from amycolatopsis methanolica
    FEBS Journal, 1993
    Co-Authors: Peter W Van Ophem, Jozef Van Beeumen, J A Duine
    Abstract:

    Extracts of Gram-positive bacteria like Rhodococcus rhodochrous, Rhodococcus erythropolis and Amycolatopsis methanolica, but not those of several Gram-negative ones, showed dehydrogenase activity for ethanol as well as for methanol when 4-nitroso-N, N-dimethylaniline (NDMA) was used as electron acceptor. Chromatography of extracts of the first two organisms revealed one activity for both substrates, that of A. methanolica two activities, one of which is able to oxidize methanol and has been purified (Bystrykh, L. V., Govorukhina, N. I., van Ophem, P. W., Hektor, H. J., Dijkhuizen, L. and Duine, J. A., unpublished results). The other, indicated as NDMA-dependent alcohol dehydrogenase (NDMA-ADH), was purified to homogeneity. It is a trimeric enzyme consisting of subunits of 39 kDa and one firmly bound NAD as cofactor. Although NDMA-ADH shows structural similarity with the long-chain, zinc-containing, NAD(P)-dependent alcohol dehydrogenases with respect to the N-terminal sequence up to residue 41 (56% identity with horse liver alcohol dehydrogenase), the enzymes are catalytically different since NDMA-ADH is unable to use NAD(P)(H) as a coenzyme and NAD(P)-dependent alcohol dehydrogenases are inactive with NDMA (in the absence of NAD). Comparison of the NDMA-ADH properties with those of the methanol-oxidizing enzyme of A. methanolica, Mycobacterium gastri and Bacillus methanolica C1, and formAldehyde dismutase of Pseudomonas putida F61 revealed large differences in structural as well as catalytic properties, in spite of the fact that all are nicotinoproteins [enzymes which have bound NAD(P) as a cofactor]. It is concluded, therefore, that NDMA-ADH is a novel type of nicotinoprotein alcohol dehydrogenase.