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Seo JH, Kyung D, Joo K, Lee J, Kim BG. Necessary and sufficient conditions for the asymmetric synthesis of chiral amines using ω-aminotransferases. Biotechnol Bioeng 2010; 108:253-63. [DOI: 10.1002/bit.22930] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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52
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Cassimjee KE, Branneby C, Abedi V, Wells A, Berglund P. Transaminations with isopropyl amine: equilibrium displacement with yeast alcohol dehydrogenase coupled to in situ cofactor regeneration. Chem Commun (Camb) 2010; 46:5569-71. [DOI: 10.1039/c0cc00050g] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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53
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Fuchs M, Koszelewski D, Tauber K, Kroutil W, Faber K. Chemoenzymatic asymmetric total synthesis of (S)-Rivastigmine using ω-transaminases. Chem Commun (Camb) 2010; 46:5500-2. [DOI: 10.1039/c0cc00585a] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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54
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Biocatalytic asymmetric amination of carbonyl functional groups - a synthetic biology approach to organic chemistry. Biotechnol J 2009; 4:1420-31. [DOI: 10.1002/biot.200900110] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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55
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Schell U, Wohlgemuth R, Ward JM. Synthesis of pyridoxamine 5′-phosphate using an MBA:pyruvate transaminase as biocatalyst. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcatb.2008.10.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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56
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Chen BH, Sayar A, Kaulmann U, Dalby PA, Ward JM, Woodley JM. Reaction modelling and simulation to assess the integrated use of transketolase and ω-transaminase for the synthesis of an aminotriol. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.1080/10242420601068668] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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57
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Truppo MD, Turner NJ, Rozzell JD. Efficient kinetic resolution of racemic amines using a transaminase in combination with an amino acid oxidase. Chem Commun (Camb) 2009:2127-9. [DOI: 10.1039/b902995h] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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58
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Berendsen WR, Lapin A, Reuss M. Investigations of Reaction Kinetics for Immobilized Enzymes-Identification of Parameters in the Presence of Diffusion Limitation. Biotechnol Prog 2008; 22:1305-12. [PMID: 17022668 DOI: 10.1021/bp060062e] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A method is proposed for identification of kinetic parameters when diffusion of substrates is limiting in reactions catalyzed by immobilized enzymes. This method overcomes conventional sequential procedures, which assume immobilization does not affect the conformation of the enzyme and, thus, consider intrinsic and inherent kinetics to be the same. The coupled equations describing intraparticle mass transport are solved simultaneously using numerical methods and are used for direct estimation of kinetic parameters by fitting modeling results to time-course measurements in a stirred tank reactor. While most traditional procedures were based on Michaelis-Menten kinetics, the method presented here is applicable to more complex kinetic mechanisms involving multiple state variables, such as ping-pong bi-bi. The method is applied to the kinetic resolution of (R/S)-1-methoxy-2-propanol with vinyl acetate catalyzed by Candida antarctica lipase B. A mathematical model is developed consisting of irreversible ping-pong bi-bi kinetics, including competitive inhibition of both enantiomers. The kinetic model, which fits to experimental data over a wide range of both substrates (5-95%) and temperatures (5-56 degrees C), is used for simulations to study typical behavior of immobilized enzyme systems.
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Affiliation(s)
- Wouter R Berendsen
- University of Stuttgart, Institute of Biochemical Engineering (IBVT), Allmandring 31, 70569 Stuttgart, Germany.
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59
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Chen BH, Hibbert EG, Dalby PA, Woodley JM. A new approach to bioconversion reaction kinetic parameter identification. AIChE J 2008. [DOI: 10.1002/aic.11545] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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60
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Kaulmann U, Smithies K, Smith ME, Hailes HC, Ward JM. Substrate spectrum of ω-transaminase from Chromobacterium violaceum DSM30191 and its potential for biocatalysis. Enzyme Microb Technol 2007. [DOI: 10.1016/j.enzmictec.2007.05.011] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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61
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Yi SS, Lee CW, Kim J, Kyung D, Kim BG, Lee YS. Covalent immobilization of ω-transaminase from Vibrio fluvialis JS17 on chitosan beads. Process Biochem 2007. [DOI: 10.1016/j.procbio.2007.01.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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62
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Lee CW, Yi SS, Kim J, Lee YS, Kim BG. Improved immobilized enzyme systems using spherical micro silica sol-gel enzyme beads. BIOTECHNOL BIOPROC E 2006. [DOI: 10.1007/bf03026240] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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63
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Berendsen WR, Gendrot G, Freund A, Reuss M. A kinetic study of lipase-catalyzed reversible kinetic resolution involving verification at miniplant-scale. Biotechnol Bioeng 2006; 95:883-92. [PMID: 16937404 DOI: 10.1002/bit.21034] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lipase-catalyzed kinetic resolution of racemates is a popular method for synthesis of chiral synthons. Most of these resolutions are reversible equilibrium limited reactions. For the first time, an extensive kinetic model is proposed for kinetic resolution reactions, which takes into account the full reversibility of the reaction, substrate inhibition by an acyl donor and an acyl acceptor as well as alternative substrate inhibition by each enantiomer. For this purpose, the reversible enantioselective transesterification of (R/S)-1-methoxy-2-propanol with ethyl acetate catalyzed by Candida antarctica lipase B (CAL-B) is investigated. The detailed model presented here is valid for a wide range of substrate and product concentrations. Following model discrimination and the application of Haldane equations to reduce the degree of freedom in parameter estimation, the 11 free parameters are successfully identified. All parameters are fitted to the complete data set simultaneously. Six types of independent initial rate studies provide a solid data basis for the model. The effect of changes in substrate and product concentration on reaction kinetics is discussed. The developed model is used for simulations to study the behavior of reaction kinetics in a fixed bed reactor. The typical plot of enantiomeric excess versus conversion of substrate and product is evaluated at various initial substrate mixtures. The model is validated by comparison with experimental results obtained with a fixed bed reactor, which is part of a fully automated state-of-the-art miniplant.
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Affiliation(s)
- W R Berendsen
- Institute of Biochemical Engineering (IBVT), University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany
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64
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Yun H, Hwang BY, Lee JH, Kim BG. Use of enrichment culture for directed evolution of the Vibrio fluvialis JS17 omega-transaminase, which is resistant to product inhibition by aliphatic ketones. Appl Environ Microbiol 2005; 71:4220-4. [PMID: 16085806 PMCID: PMC1183280 DOI: 10.1128/aem.71.8.4220-4224.2005] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel high-throughput screening method that overcame product inhibition was used to isolate a mutant omega-transaminase from Vibrio fluvialis JS17. An enzyme library was generated using error-prone PCR mutagenesis and then enriched on minimal medium containing 2-aminoheptane as the sole nitrogen source and 2-butanone as an inhibitory ketone. An identified mutant enzyme, omega-TAmla, showed significantly reduced product inhibition by aliphatic ketone. The product inhibition constants of the mutant with 2-butanone and 2-heptanone were 6- and 4.5-fold higher than those of the wild type, respectively. Using omega-TAmla (50 U/ml) overexpressed in Escherichia coli BL21, 150 mM 2-aminoheptane was successfully resolved to (R)-2-aminoheptane (enantiomeric excess, >99%) with 53% conversion with an enantioselectivity of >100.
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Affiliation(s)
- Hyungdon Yun
- School of Chemical Engineering and Institute of Molecular Biology and Genetics, Seoul National University, Seoul, South Korea
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65
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Yun H, Lim S, Cho BK, Kim BG. omega-Amino acid:pyruvate transaminase from Alcaligenes denitrificans Y2k-2: a new catalyst for kinetic resolution of beta-amino acids and amines. Appl Environ Microbiol 2004; 70:2529-34. [PMID: 15066855 PMCID: PMC383019 DOI: 10.1128/aem.70.4.2529-2534.2004] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alcaligenes denitrificans Y2k-2 was obtained by selective enrichment followed by screening from soil samples, which showed omega-amino acid:pyruvate transaminase activity, to kinetically resolve aliphatic beta-amino acid, and the corresponding structural gene (aptA) was cloned. The gene was functionally expressed in Escherichia coli BL21 by using an isopropyl-beta-D-thiogalactopyranoside (IPTG)-inducible pET expression system (9.6 U/mg), and the recombinant AptA was purified to show a specific activity of 77.2 U/mg for L-beta-amino-n-butyric acid (L-beta-ABA). The enzyme converts various beta-amino acids and amines to the corresponding beta-keto acids and ketones by using pyruvate as an amine acceptor. The apparent K(m) and V(max) for L-beta-ABA were 56 mM and 500 U/mg, respectively, in the presence of 10 mM pyruvate. In the presence of 10 mM L-beta-ABA, the apparent K(m) and V(max) for pyruvate were 11 mM and 370 U/mg, respectively. The enzyme exhibits high stereoselectivity (E > 80) in the kinetic resolution of 50 mM D,L-beta-ABA, producing optically pure D-beta-ABA (99% enantiomeric excess) with 53% conversion.
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Affiliation(s)
- Hyungdon Yun
- Institute for Molecular Biology and Genetics and School of Chemical Engineering, Seoul National University, Seoul 151-742, Korea
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66
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Yun H, Cho BK, Kim BG. Kinetic resolution of (R,S)-sec-butylamine using omega-transaminase fromVibrio fluvialis JS17 under reduced pressure. Biotechnol Bioeng 2004; 87:772-8. [PMID: 15329935 DOI: 10.1002/bit.20186] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The kinetic resolution of (R,S) sec-butylamine with the omega-transaminase (TA) from Vibrio fluvialis JS17 was performed under reduced pressure (e.g., 150 torr) to selectively remove an inhibitory product (2-butanone). The evaporation kinetics of 2-butanone at 150 torr in the buffer solution followed the first-order rate law, and the evaporation rate constant was 2.19 1/h, and independent of pH, while the evaporation kinetics of sec-butylamine is dependent on pH. A simple mathematical model of the evaporation of sec-butylamine allowing the estimation of its concentration in the reaction media was developed. The evaporation rate constant of its free amine form and the protonated amine form were 1.00 1/h, and nearly zero, respectively. Although the optimum pH of the omega-TA activity for sec-butylamine is 9.0, the optimal pH of the enzyme reaction under reduced pressure was pH 7.0, due to the higher evaporation rate of sec-butylamine at higher pH above 7.0. Using the recombinant Escherichia coli BL21 overexpressing omega-TA, 400 mM racemic sec-butylamine was resolved successfully to 98% ee of (R)-sec-butylamine with 53% conversion at 150 torr and pH 7.0.
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Affiliation(s)
- Hyungdon Yun
- Laboratory of Molecular Biotechnology and Biomaterials, Institute for Molecular Biology and Genetics, Seoul National University, 151-742, Korea
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67
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Cho BK, Seo JH, Kang TW, Kim BG. Asymmetric synthesis of L-homophenylalanine by equilibrium-shift using recombinant aromatic L-amino acid transaminase. Biotechnol Bioeng 2003; 83:226-34. [PMID: 12768628 DOI: 10.1002/bit.10661] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
L-Homophenylalanine (L-HPA) was asymmetrically synthesized from 2-oxo-4-phenylbutyric acid (2-OPBA) and L-aspartate using a recombinant aromatic amino acid transaminase (AroAT). To screen microorganisms having such an L-specific AroAT with a relaxed substrate inhibition in the asymmetric synthesis of unnatural amino acids, enrichment cultures were performed in a minimal media containing 50 mM L-HPA as a sole nitrogen source. To reduce the intracellular background synthetic activity by amino acid pools in the cells, a two-step screening method was used. The putative AroAT (i.e., AroATEs) from the screened Enterobacter sp. BK2K-1 was cloned, sequenced, and overexpressed in E. coli cells. The activity of the overexpressed AroATEs was 314-fold higher than that of the wild-type cell. The substrate specificities of the enzyme and homology search revealed that the cloned transaminase is true AroAT. The AroATEs showed a substrate inhibition by 2-OPBA from 40 mM in the asymmetric synthesis, which made it difficult to perform batch asymmetric synthesis of L-HPA at high concentrations of 2-OPBA. To avoid the substrate inhibition by 2-OPBA, intermittent addition of the solid-state substrate was attempted to obtain a high concentration of L-HPA. By using the cell extract (75 U) obtained from the recombinant E. coli harboring the AroATEs gene, the asymmetric synthesis of L-HPA at 840 mM of 2-OPBA resulted in >94% of conversion yield and >99% ee of L-HPA of optical purity. Due to the low solubility (<2 mM) of L-HPA in the reaction buffer, synthesized L-HPA was continuously precipitated in the reaction media, which drives the reaction equilibrium towards the product formation. After full completion of the reaction, L-HPA of high purity (>99% ee) was easily recovered by simple pH shift of the reaction media. This method can permit very efficient asymmetric synthesis of other unnatural amino acids using a single transaminase reaction.
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Affiliation(s)
- Byung-Kwan Cho
- Interdisciplinary Program for Biochemical Engineering and Biotechnology, School of Chemical Engineering, and Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Korea
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68
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Shin JS, Yun H, Jang JW, Park I, Kim BG. Purification, characterization, and molecular cloning of a novel amine:pyruvate transaminase from Vibrio fluvialis JS17. Appl Microbiol Biotechnol 2003; 61:463-71. [PMID: 12687298 DOI: 10.1007/s00253-003-1250-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2002] [Revised: 12/25/2002] [Accepted: 01/03/2003] [Indexed: 10/25/2022]
Abstract
A transaminase from Vibrio fluvialis JS17 showing activity toward chiral amines was purified to homogeneity and its enzymatic properties were characterized. The transaminase showed an apparent molecular mass of 100 kDa as determined by gel filtration chromatography and a subunit mass of 50 kDa by MALDI-TOF mass spectrometry, suggesting a dimeric structure. The enzyme had an isoelectric point of 5.4 and its absorption spectrum exhibited maxima at 320 and 405 nm. The optimal pH and temperature for enzyme activity were 9.2 and 37 degrees C, respectively. Pyruvate and pyridoxal 5'-phosphate increased enzyme stability whereas (S)-alpha-methylbenzylamine reversibly inactivated the enzyme. The transaminase gene was cloned from a V. fluvialis JS17 genomic library. The deduced amino acid sequence (453 residues) showed significant homology with omega-amino acid:pyruvate transaminases (omega-APT) from various bacterial strains (80 identical residues with four omega-APTs). However, of 159 conserved residues in the four omega-APTs, 79 were not conserved in the transaminase from V. fluvialis JS17. Taken together with the sequence homology results, and the lack of activity toward beta-alanine (a typical amino donor for the omega-APT), the results suggest that the transaminase is a novel amine:pyruvate transaminase that has not been reported to date.
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Affiliation(s)
- J-S Shin
- Bioengineering, Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125, USA
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69
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Shin JS, Kim BG. Substrate inhibition mode of omega-transaminase from Vibrio fluvialis JS17 is dependent on the chirality of substrate. Biotechnol Bioeng 2002; 77:832-7. [PMID: 11835144 DOI: 10.1002/bit.10165] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Substrate inhibition is a common phenomenon in enzyme chemistry, which is observed only with a fast-reacting substrate enantiomer. We report here for the first time substrate inhibition of an enantioselective enzyme by both substrate enantiomers. The enantioselective substrate inhibition, i.e., different mode of inhibition by each substrate enantiomer, of (S)-specific omega-transaminase was found with various chiral amines. A kinetic model based on ping-pong bi-bi mechanism has been developed and kinetic parameters were measured. The kinetic model reveals that the inhibition by (R)-amine results from formation of Michaelis complex with enzyme-pyridoxal 5'-phosphate, whereas the inhibition by (S)-amine results from the formation of the complex with enzyme-pyridoxamine 5'-phosphate. Substrate inhibition constants (K(SI)) of each (S)-enantiomer of four chiral amines showed a linear correlation with those of cognate (R)-amines. Such a correlation was also found between the K(SI) values and Michaelis constants of (S)-amines. These correlations indicate that recognition mechanisms and active site structures of both enzyme-pyridoxal 5'-phosphate, enzyme-pyridoxamine 5'-phosphate are similar. Taken together with the results, high propensity for non-productive substrate binding strongly suggests that binding pockets of the omega-transaminase is loosely defined, which accounts for the enantioselective substrate inhibition.
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70
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Shin JS, Kim BG, Shin DH. Kinetic resolution of chiral amines using packed-bed reactor. Enzyme Microb Technol 2001. [DOI: 10.1016/s0141-0229(01)00382-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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71
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Shin JS, Kim BG, Liese A, Wandrey C. Kinetic resolution of chiral amines with omega-transaminase using an enzyme-membrane reactor. Biotechnol Bioeng 2001; 73:179-87. [PMID: 11257600 DOI: 10.1002/bit.1050] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A kinetic resolution process for the production of chiral amines was developed using an enzyme-membrane reactor (EMR) and a hollow-fiber membrane contactor with (S)-specific omega-transaminases (omega-TA) from Vibrio fluvialis JS17 and Bacillus thuringiensis JS64. The substrate solution containing racemic amine and pyruvate was recirculated through the EMR and inhibitory ketone product was selectively extracted by the membrane contactor until enantiomeric excess of (R)-amine exceeded 95%. Using the reactor set-up with flat membrane reactor (10-mL working volume), kinetic resolutions of alpha-methylbenzylamine (alpha-MBA) and 1-aminotetralin (200 mM, 50 mL) were carried out. During the operation, concentration of ketone product, i.e., acetophenone or alpha-tetralone, in a substrate reservoir was maintained below 0.1 mM, suggesting efficient removal of the inhibitory ketone by the membrane contactor. After 47 and 32.5 h of operation using 5 U/mL of enzyme, 98.0 and 95.5% ee of (R)-alpha-MBA and (R)-1-aminotetralin were obtained at 49.5 and 48.8% of conversion, respectively. A hollow-fiber membrane reactor (39-mL working volume) was used for a preparative-scale kinetic resolution of 1-aminotetralin (200 mM, 1 L). After 133 h of operation, enantiomeric excess reached 95.6% and 14.3 g of (R)-1-aminotetralin was recovered (97.4% of yield). Mathematical modeling of the EMR process including the membrane contactor was performed to evaluate the effect of residence time. The simulation results suggest that residence time should be short to maintain the concentration of the ketone product in EMR sufficiently low so as to decrease conversion per cycle and, in turn, reduce the inhibition of the omega-TA activity.
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Affiliation(s)
- J S Shin
- School of Chemical Engineering and Institute for Molecular Biology and Genetics, Seoul National University, Seoul, Korea
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72
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Hacisalihoglu A, Jongejan A, Jongejan JA, Duine JA. Enantioselective oxidation of amphetamine by copper-containing quinoprotein amine oxidases from Escherichia coli and Klebsiella oxytoca. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s1381-1177(00)00216-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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73
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74
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Modeling of the kinetic resolution of α-methylbenzylamine with ω-transaminase in a two-liquid-phase system. Enzyme Microb Technol 1999. [DOI: 10.1016/s0141-0229(99)00067-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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