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Musa M Musa - One of the best experts on this subject based on the ideXlab platform.
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expanding the substrate specificity of thermoanaerobacter pseudoethanolicus Secondary Alcohol dehydrogenase by a dual site mutation
European Journal of Organic Chemistry, 2018Co-Authors: Musa M Musa, Claire Vieille, Masateru Takahashi, Odey Bsharat, Ibrahim Karume, Samir M HamdanAbstract:The authors acknowledge the support provided by the Deanship of Scientific Research (DSR) at King Fahd University of Petroleum and Minerals (KFUPM) for funding this work under project number IN151032. They also acknowledge the supported by baseline research fund to S.M.H. by King Abdullah University of Science and Technology.
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Deracemization of Secondary Alcohols by using a Single Alcohol Dehydrogenase
Chemcatchem, 2016Co-Authors: Ibrahim Karume, Samir M Hamdan, Masateru Takahashi, Musa M MusaAbstract:We developed a single-enzyme-mediated two-step approach for deracemization of Secondary Alcohols. A single mutant of Thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase enables the nonstereoselective oxidation of racemic Alcohols to ketones, followed by a stereoselective reduction process. Varying the amounts of acetone and 2-propanol cosubstrates controls the stereoselectivities of the consecutive oxidation and reduction reactions, respectively. We used one enzyme to accomplish the deracemization of Secondary Alcohols with up to >99 % ee and >99.5 % recovery in one pot and without the need to isolate the prochiral ketone intermediate.
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mutation of thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase at trp 110 affects stereoselectivity of aromatic ketone reduction
Organic and Biomolecular Chemistry, 2014Co-Authors: Jay M Patel, Musa M Musa, Luis Rodriguez, Dewey A Sutton, Vladimir V Popik, Robert S PhillipsAbstract:Alcohol dehydrogenases (ADHs) are enzymes that catalyze the reversible reduction of carbonyl compounds to their corresponding Alcohols. We have been studying a thermostable, nicotinamide-adenine dinucleotide phosphate (NADP+)-dependent, Secondary ADH from Thermoanaerobacter ethanolicus (TeSADH). In the current work, we expanded our library of TeSADH and adopted the site-saturation mutagenesis approach in creating a comprehensive mutant library at W110. We used phenylacetone as a model substrate to study the effectiveness of our library because this substrate showed low enantioselectivity in our previous work when reduced using W110A TeSADH. Five of the newly designed W110 mutants reduced phenylacetone at >99.9% ee, and two of these mutants exhibit an enantiomeric ratio (E-value) of over 100. These five mutants also reduced 1-phenyl-2-butanone and 4-phenyl-2-butanone to their corresponding (S)-configured Alcohols in >99.9% ee. These new mutants of TeSADH will likely have synthetic utility for reduction of aromatic ketones in the future.
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racemization of enantiopure Secondary Alcohols by thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase
Organic and Biomolecular Chemistry, 2013Co-Authors: Musa M Musa, Robert S Phillips, Maris Laivenieks, Claire Vieille, Masateru Takahashi, Samir M HamdanAbstract:Controlled racemization of enantiopure phenyl-ring-containing Secondary Alcohols is achieved in this study using W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TeSADH) and in the presence of the reduced and oxidized forms of its cofactor nicotinamide-adenine dinucleotide. Racemization of both enantiomers of Alcohols accepted by W110A TeSADH, not only with low, but also with reasonably high, enantiomeric discrimination is achieved by this method. Furthermore, the high tolerance of TeSADH to organic solvents allows TeSADH-catalyzed racemization to be conducted in media containing up to 50% (v/v) of organic solvents.
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xerogel encapsulated w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus performs asymmetric reduction of hydrophobic ketones in organic solvents
Angewandte Chemie, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, Gregory J Zeikus, Robert S PhillipsAbstract:Theasymmetricreductionofketonesandthekinetic resolution (KR)of racemic Alcohols are the mostimportant reactions for producing optically active Alcoholsthat then can be used to synthesize industrially importantcompounds like natural products.Apractical technique toimprove enzyme performanceisenzyme immobilization.
Robert S Phillips - One of the best experts on this subject based on the ideXlab platform.
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mutation of thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase at trp 110 affects stereoselectivity of aromatic ketone reduction
Organic and Biomolecular Chemistry, 2014Co-Authors: Jay M Patel, Musa M Musa, Luis Rodriguez, Dewey A Sutton, Vladimir V Popik, Robert S PhillipsAbstract:Alcohol dehydrogenases (ADHs) are enzymes that catalyze the reversible reduction of carbonyl compounds to their corresponding Alcohols. We have been studying a thermostable, nicotinamide-adenine dinucleotide phosphate (NADP+)-dependent, Secondary ADH from Thermoanaerobacter ethanolicus (TeSADH). In the current work, we expanded our library of TeSADH and adopted the site-saturation mutagenesis approach in creating a comprehensive mutant library at W110. We used phenylacetone as a model substrate to study the effectiveness of our library because this substrate showed low enantioselectivity in our previous work when reduced using W110A TeSADH. Five of the newly designed W110 mutants reduced phenylacetone at >99.9% ee, and two of these mutants exhibit an enantiomeric ratio (E-value) of over 100. These five mutants also reduced 1-phenyl-2-butanone and 4-phenyl-2-butanone to their corresponding (S)-configured Alcohols in >99.9% ee. These new mutants of TeSADH will likely have synthetic utility for reduction of aromatic ketones in the future.
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racemization of enantiopure Secondary Alcohols by thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase
Organic and Biomolecular Chemistry, 2013Co-Authors: Musa M Musa, Robert S Phillips, Maris Laivenieks, Claire Vieille, Masateru Takahashi, Samir M HamdanAbstract:Controlled racemization of enantiopure phenyl-ring-containing Secondary Alcohols is achieved in this study using W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TeSADH) and in the presence of the reduced and oxidized forms of its cofactor nicotinamide-adenine dinucleotide. Racemization of both enantiomers of Alcohols accepted by W110A TeSADH, not only with low, but also with reasonably high, enantiomeric discrimination is achieved by this method. Furthermore, the high tolerance of TeSADH to organic solvents allows TeSADH-catalyzed racemization to be conducted in media containing up to 50% (v/v) of organic solvents.
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xerogel encapsulated w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus performs asymmetric reduction of hydrophobic ketones in organic solvents
Angewandte Chemie, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, Gregory J Zeikus, Robert S PhillipsAbstract:Theasymmetricreductionofketonesandthekinetic resolution (KR)of racemic Alcohols are the mostimportant reactions for producing optically active Alcoholsthat then can be used to synthesize industrially importantcompounds like natural products.Apractical technique toimprove enzyme performanceisenzyme immobilization.
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a thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase mutant derivative highly active and stereoselective on phenylacetone and benzylacetone
Protein Engineering Design & Selection, 2007Co-Authors: Karla I Ziegelmannfjeld, Musa M Musa, Robert S Phillips, Gregory J Zeikus, Claire VieilleAbstract:The Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus 39E (TeSADH) is highly thermostable and solvent-stable, and it is active on a broad range of substrates. These properties make TeSADH an excellent template to engineer an industrial catalyst for chiral chemical synthesis. (S)-1-Phenyl-2-propanol was our target product because it is a precursor to major pharmaceuticals containing Secondary Alcohol groups. TeSADH has no detectable activity on this Alcohol, but it is highly active on 2-butanol. The structural model we used to plan our mutagenesis strategy was based on the substrate's orientation in a horse liver Alcohol dehydrogenase*p-bromobenzyl Alcohol*NAD(+) ternary complex (PDB entry 1HLD). The W110A TeSADH mutant now uses (S)-1-phenyl-2-propanol, (S)-4-phenyl-2-butanol and the corresponding ketones as substrates. W110A TeSADH's kinetic parameters on these substrates are in the same range as those of TeSADH on 2-butanol, making W110A TeSADH an excellent catalyst. In particular, W110A TeSADH is twice as efficient on benzylacetone as TeSADH is on 2-butanol, and it produces (S)-4-phenyl-2-butanol from benzylacetone with an enantiomeric excess above 99%. W110A TeSADH is optimally active at 87.5 degrees C and remains highly thermostable. W110A TeSADH is active on aryl derivatives of phenylacetone and benzylacetone, making this enzyme a potentially useful catalyst for the chiral synthesis of aryl derivatives of Alcohols. As a control in our engineering approach, we used the TbSADH*(S)-2-butanol binary complex (PDB entry 1BXZ) as the template to model a mutation that would make TeSADH active on (S)-1-phenyl-2-propanol. Mutant Y267G TeSADH did not have the substrate specificity predicted in this modeling study. Our results suggest that (S)-2-butanol's orientation in the TbSADH*(S)-2-butanol binary complex does not reflect its orientation in the ternary enzyme-substrate-cofactor complex.
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asymmetric reduction and oxidation of aromatic ketones and Alcohols using w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus
Journal of Organic Chemistry, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, And Gregory J Zeikus, Robert S PhillipsAbstract:An enantioselective asymmetric reduction of phenyl ring-containing prochiral ketones to yield the corresponding optically active Secondary Alcohols was achieved with W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TESADH) in Tris buffer using 2-propanol (30%, v/v) as cosolvent and cosubstrate. This concentration of 2-propanol was crucial not only to enhance the solubility of hydrophobic phenyl ring-containing substrates in the aqueous reaction medium, but also to shift the equilibrium in the reduction direction. The resulting Alcohols have S-configuration, in agreement with Prelog's rule, in which the nicotinamide-adenine dinucleotide phosphate (NADPH) cofactor transfers its pro-R hydride to the re face of the ketone. A series of phenyl ring-containing ketones, such as 4-phenyl-2-butanone (1a) and 1-phenyl-1,3-butadione (2a), were reduced with good to excellent yields and high enantioselectivities. On the other hand, 1-phenyl-2-propanone (7a) was reduced with lower ee than...
Claire Vieille - One of the best experts on this subject based on the ideXlab platform.
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expanding the substrate specificity of thermoanaerobacter pseudoethanolicus Secondary Alcohol dehydrogenase by a dual site mutation
European Journal of Organic Chemistry, 2018Co-Authors: Musa M Musa, Claire Vieille, Masateru Takahashi, Odey Bsharat, Ibrahim Karume, Samir M HamdanAbstract:The authors acknowledge the support provided by the Deanship of Scientific Research (DSR) at King Fahd University of Petroleum and Minerals (KFUPM) for funding this work under project number IN151032. They also acknowledge the supported by baseline research fund to S.M.H. by King Abdullah University of Science and Technology.
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racemization of enantiopure Secondary Alcohols by thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase
Organic and Biomolecular Chemistry, 2013Co-Authors: Musa M Musa, Robert S Phillips, Maris Laivenieks, Claire Vieille, Masateru Takahashi, Samir M HamdanAbstract:Controlled racemization of enantiopure phenyl-ring-containing Secondary Alcohols is achieved in this study using W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TeSADH) and in the presence of the reduced and oxidized forms of its cofactor nicotinamide-adenine dinucleotide. Racemization of both enantiomers of Alcohols accepted by W110A TeSADH, not only with low, but also with reasonably high, enantiomeric discrimination is achieved by this method. Furthermore, the high tolerance of TeSADH to organic solvents allows TeSADH-catalyzed racemization to be conducted in media containing up to 50% (v/v) of organic solvents.
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xerogel encapsulated w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus performs asymmetric reduction of hydrophobic ketones in organic solvents
Angewandte Chemie, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, Gregory J Zeikus, Robert S PhillipsAbstract:Theasymmetricreductionofketonesandthekinetic resolution (KR)of racemic Alcohols are the mostimportant reactions for producing optically active Alcoholsthat then can be used to synthesize industrially importantcompounds like natural products.Apractical technique toimprove enzyme performanceisenzyme immobilization.
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a thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase mutant derivative highly active and stereoselective on phenylacetone and benzylacetone
Protein Engineering Design & Selection, 2007Co-Authors: Karla I Ziegelmannfjeld, Musa M Musa, Robert S Phillips, Gregory J Zeikus, Claire VieilleAbstract:The Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus 39E (TeSADH) is highly thermostable and solvent-stable, and it is active on a broad range of substrates. These properties make TeSADH an excellent template to engineer an industrial catalyst for chiral chemical synthesis. (S)-1-Phenyl-2-propanol was our target product because it is a precursor to major pharmaceuticals containing Secondary Alcohol groups. TeSADH has no detectable activity on this Alcohol, but it is highly active on 2-butanol. The structural model we used to plan our mutagenesis strategy was based on the substrate's orientation in a horse liver Alcohol dehydrogenase*p-bromobenzyl Alcohol*NAD(+) ternary complex (PDB entry 1HLD). The W110A TeSADH mutant now uses (S)-1-phenyl-2-propanol, (S)-4-phenyl-2-butanol and the corresponding ketones as substrates. W110A TeSADH's kinetic parameters on these substrates are in the same range as those of TeSADH on 2-butanol, making W110A TeSADH an excellent catalyst. In particular, W110A TeSADH is twice as efficient on benzylacetone as TeSADH is on 2-butanol, and it produces (S)-4-phenyl-2-butanol from benzylacetone with an enantiomeric excess above 99%. W110A TeSADH is optimally active at 87.5 degrees C and remains highly thermostable. W110A TeSADH is active on aryl derivatives of phenylacetone and benzylacetone, making this enzyme a potentially useful catalyst for the chiral synthesis of aryl derivatives of Alcohols. As a control in our engineering approach, we used the TbSADH*(S)-2-butanol binary complex (PDB entry 1BXZ) as the template to model a mutation that would make TeSADH active on (S)-1-phenyl-2-propanol. Mutant Y267G TeSADH did not have the substrate specificity predicted in this modeling study. Our results suggest that (S)-2-butanol's orientation in the TbSADH*(S)-2-butanol binary complex does not reflect its orientation in the ternary enzyme-substrate-cofactor complex.
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asymmetric reduction and oxidation of aromatic ketones and Alcohols using w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus
Journal of Organic Chemistry, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, And Gregory J Zeikus, Robert S PhillipsAbstract:An enantioselective asymmetric reduction of phenyl ring-containing prochiral ketones to yield the corresponding optically active Secondary Alcohols was achieved with W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TESADH) in Tris buffer using 2-propanol (30%, v/v) as cosolvent and cosubstrate. This concentration of 2-propanol was crucial not only to enhance the solubility of hydrophobic phenyl ring-containing substrates in the aqueous reaction medium, but also to shift the equilibrium in the reduction direction. The resulting Alcohols have S-configuration, in agreement with Prelog's rule, in which the nicotinamide-adenine dinucleotide phosphate (NADPH) cofactor transfers its pro-R hydride to the re face of the ketone. A series of phenyl ring-containing ketones, such as 4-phenyl-2-butanone (1a) and 1-phenyl-1,3-butadione (2a), were reduced with good to excellent yields and high enantioselectivities. On the other hand, 1-phenyl-2-propanone (7a) was reduced with lower ee than...
Samir M Hamdan - One of the best experts on this subject based on the ideXlab platform.
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expanding the substrate specificity of thermoanaerobacter pseudoethanolicus Secondary Alcohol dehydrogenase by a dual site mutation
European Journal of Organic Chemistry, 2018Co-Authors: Musa M Musa, Claire Vieille, Masateru Takahashi, Odey Bsharat, Ibrahim Karume, Samir M HamdanAbstract:The authors acknowledge the support provided by the Deanship of Scientific Research (DSR) at King Fahd University of Petroleum and Minerals (KFUPM) for funding this work under project number IN151032. They also acknowledge the supported by baseline research fund to S.M.H. by King Abdullah University of Science and Technology.
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Deracemization of Secondary Alcohols by using a Single Alcohol Dehydrogenase
Chemcatchem, 2016Co-Authors: Ibrahim Karume, Samir M Hamdan, Masateru Takahashi, Musa M MusaAbstract:We developed a single-enzyme-mediated two-step approach for deracemization of Secondary Alcohols. A single mutant of Thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase enables the nonstereoselective oxidation of racemic Alcohols to ketones, followed by a stereoselective reduction process. Varying the amounts of acetone and 2-propanol cosubstrates controls the stereoselectivities of the consecutive oxidation and reduction reactions, respectively. We used one enzyme to accomplish the deracemization of Secondary Alcohols with up to >99 % ee and >99.5 % recovery in one pot and without the need to isolate the prochiral ketone intermediate.
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racemization of enantiopure Secondary Alcohols by thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase
Organic and Biomolecular Chemistry, 2013Co-Authors: Musa M Musa, Robert S Phillips, Maris Laivenieks, Claire Vieille, Masateru Takahashi, Samir M HamdanAbstract:Controlled racemization of enantiopure phenyl-ring-containing Secondary Alcohols is achieved in this study using W110A Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus (W110A TeSADH) and in the presence of the reduced and oxidized forms of its cofactor nicotinamide-adenine dinucleotide. Racemization of both enantiomers of Alcohols accepted by W110A TeSADH, not only with low, but also with reasonably high, enantiomeric discrimination is achieved by this method. Furthermore, the high tolerance of TeSADH to organic solvents allows TeSADH-catalyzed racemization to be conducted in media containing up to 50% (v/v) of organic solvents.
Gregory J Zeikus - One of the best experts on this subject based on the ideXlab platform.
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xerogel encapsulated w110a Secondary Alcohol dehydrogenase from thermoanaerobacter ethanolicus performs asymmetric reduction of hydrophobic ketones in organic solvents
Angewandte Chemie, 2007Co-Authors: Musa M Musa, Claire Vieille, Karla I Ziegelmannfjeld, Gregory J Zeikus, Robert S PhillipsAbstract:Theasymmetricreductionofketonesandthekinetic resolution (KR)of racemic Alcohols are the mostimportant reactions for producing optically active Alcoholsthat then can be used to synthesize industrially importantcompounds like natural products.Apractical technique toimprove enzyme performanceisenzyme immobilization.
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a thermoanaerobacter ethanolicus Secondary Alcohol dehydrogenase mutant derivative highly active and stereoselective on phenylacetone and benzylacetone
Protein Engineering Design & Selection, 2007Co-Authors: Karla I Ziegelmannfjeld, Musa M Musa, Robert S Phillips, Gregory J Zeikus, Claire VieilleAbstract:The Secondary Alcohol dehydrogenase from Thermoanaerobacter ethanolicus 39E (TeSADH) is highly thermostable and solvent-stable, and it is active on a broad range of substrates. These properties make TeSADH an excellent template to engineer an industrial catalyst for chiral chemical synthesis. (S)-1-Phenyl-2-propanol was our target product because it is a precursor to major pharmaceuticals containing Secondary Alcohol groups. TeSADH has no detectable activity on this Alcohol, but it is highly active on 2-butanol. The structural model we used to plan our mutagenesis strategy was based on the substrate's orientation in a horse liver Alcohol dehydrogenase*p-bromobenzyl Alcohol*NAD(+) ternary complex (PDB entry 1HLD). The W110A TeSADH mutant now uses (S)-1-phenyl-2-propanol, (S)-4-phenyl-2-butanol and the corresponding ketones as substrates. W110A TeSADH's kinetic parameters on these substrates are in the same range as those of TeSADH on 2-butanol, making W110A TeSADH an excellent catalyst. In particular, W110A TeSADH is twice as efficient on benzylacetone as TeSADH is on 2-butanol, and it produces (S)-4-phenyl-2-butanol from benzylacetone with an enantiomeric excess above 99%. W110A TeSADH is optimally active at 87.5 degrees C and remains highly thermostable. W110A TeSADH is active on aryl derivatives of phenylacetone and benzylacetone, making this enzyme a potentially useful catalyst for the chiral synthesis of aryl derivatives of Alcohols. As a control in our engineering approach, we used the TbSADH*(S)-2-butanol binary complex (PDB entry 1BXZ) as the template to model a mutation that would make TeSADH active on (S)-1-phenyl-2-propanol. Mutant Y267G TeSADH did not have the substrate specificity predicted in this modeling study. Our results suggest that (S)-2-butanol's orientation in the TbSADH*(S)-2-butanol binary complex does not reflect its orientation in the ternary enzyme-substrate-cofactor complex.
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cloning and expression of the gene encoding the thermoanaerobacter ethanolicus 39e Secondary Alcohol dehydrogenase and biochemical characterization of the enzyme
Biochemical Journal, 1996Co-Authors: Douglas S Burdette, Claire Vieille, Gregory J ZeikusAbstract:The adhB gene encoding Thermoanaerobacter ethanolicus 39E Secondary-Alcohol dehydrogenase (S-ADH) was cloned, sequenced and expressed in Escherichia coli. The 1056 bp gene encodes a homotetrameric recombinant enzyme consisting of 37.7 kDa subunits. The purified recombinant enzyme is optimally active above 90 ∞C with a half-life of approx. 1.7 h at 90 ∞C. An NADP(H)-dependent enzyme, the recombinant S-ADH has 1400-fold greater catalytic eciency in propan-2-ol oxidation than in ethanol oxidation. The enzyme was inactivated by chemical modification with dithionitrobenzoate (DTNB) and diethylpyrocarbonate, indicating that Cys and His residues are involved in catalysis. Zinc was the only metal enhancing S-ADH reactivation after DTNB modification, implicating the involvement of bound zinc in catalysis. Arrhenius plots for the oxidation
