1
|
Wang L, Tang H, Zhu H, Xue Y, Zheng Y. Enhancement of the substrate specificity of D-amino acid oxidase based on tunnel-pocket engineering. Biotechnol Bioeng 2023; 120:3557-3569. [PMID: 37650151 DOI: 10.1002/bit.28541] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/11/2023] [Accepted: 08/20/2023] [Indexed: 09/01/2023]
Abstract
D-Amino acid oxidase (DAAO) selectively catalyzes the oxidative deamination of D-amino acids, making it one of the most promising routes for synthesizing optically pure L-amino acids, including L-phosphinothricin ( L-PPT), a chiral herbicide with significant market potential. However, the native DAAOs that have been reported have low activity against unnatural acid substrate D-PPT. Herein, we designed and screened a DAAO from Rhodotorula taiwanensis (RtwDAAO), and improved its catalytic potential toward D-PPT through protein engineering. A semirational design approach was employed to create a mutation library based on the tunnel-pocket engineering. After three rounds of iterative saturation mutagenesis, the optimal variant M3rd -SHVG was obtained, exhibiting a >2000-fold increase in relative activity. The kinetic parameters showed that M3rd -SHVG improved the substrate binding affinity and turnover number. This is the optimal parameter reported so far. Further, molecular dynamics simulation revealed that the M3rd -SHVG reshapes the tunnel-pocket and corrects the direction of enzyme-substrate binding, allowing efficiently catalyze unnatural substrates. Our strategy demonstrates that the redesign of tunnel-pockets is effective in improving the activity and kinetic efficiency of DAAO, which provides a valuable reference for enzymatic catalysis. With the M3rd -SHVG as biocatalyst, 500 mM D, L-PPT was completely converted and the yield reached 98%. The results laid the foundation for further industrial production.
Collapse
Affiliation(s)
- Liuyu Wang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, P. R. China
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Heng Tang
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, P. R. China
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Hongli Zhu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, P. R. China
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Yaping Xue
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, P. R. China
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, P. R. China
| | - Yuguo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, P. R. China
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, P. R. China
| |
Collapse
|
2
|
Ju S, Kuzelka KP, Guo R, Krohn-Hansen B, Wu J, Nair SK, Yang Y. A biocatalytic platform for asymmetric alkylation of α-keto acids by mining and engineering of methyltransferases. Nat Commun 2023; 14:5704. [PMID: 37709735 PMCID: PMC10502145 DOI: 10.1038/s41467-023-40980-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 08/17/2023] [Indexed: 09/16/2023] Open
Abstract
Catalytic asymmetric α-alkylation of carbonyl compounds represents a long-standing challenge in synthetic organic chemistry. Herein, we advance a dual biocatalytic platform for the efficient asymmetric alkylation of α-keto acids. First, guided by our recently obtained crystal structures, we develop SgvMVAV as a general biocatalyst for the enantioselective methylation, ethylation, allylation and propargylation of a range of α-keto acids with total turnover numbers (TTNs) up to 4,600. Second, we mine a family of bacterial HMTs from Pseudomonas species sharing less than 50% sequence identities with known HMTs and evaluated their activities in SAM regeneration. Our best performing HMT from P. aeruginosa, PaHMT, displays the highest SAM regeneration efficiencies (TTN up to 7,700) among HMTs characterized to date. Together, the synergistic use of SgvMVAV and PaHMT affords a fully biocatalytic protocol for asymmetric methylation featuring a record turnover efficiency, providing a solution to the notorious problem of asymmetric alkylation.
Collapse
Affiliation(s)
- Shuyun Ju
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Kaylee P Kuzelka
- Department of Biochemistry, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Rui Guo
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Benjamin Krohn-Hansen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Jianping Wu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA
| | - Satish K Nair
- Department of Biochemistry, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Yang Yang
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, USA.
- Biomolecular Science and Engineering (BMSE) Program, University of California, Santa Barbara, CA, USA.
| |
Collapse
|
3
|
Bakunova AK, Kostyukov AA, Kuzmin VA, Popov VO, Bezsudnova EY. Mechanistic aspects of the transamination reactions catalyzed by D-amino acid transaminase from Haliscomenobacter hydrossis. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2023; 1871:140886. [PMID: 36496204 DOI: 10.1016/j.bbapap.2022.140886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/17/2022] [Accepted: 12/02/2022] [Indexed: 12/13/2022]
Abstract
Pyridoxal-5'-phosphate-(PLP-) dependent D-amino acid transaminases (DAATs) catalyze stereoselective reversible transfer of the amino group between D-amino acids and keto acids. In vivo DAATs are commonly known to synthesize D-glutamate for cell wall peptidoglycans. Today DAATs meet increasing attention for application in the synthesis of D-amino acids, whereas little is known about the mechanism of substrate recognition and catalytic steps of the D-amino acids conversion by DAATs. In this work, the pre-steady-state kinetics of the half-reactions of DAAT from Haliscomenobacter hydrossis with D-glutamate, D-alanine, D-leucine, and D-phenylalanine was examined at two wavelengths, 416 and 330 nm, using a stopped-flow technique. Monophasic kinetics was observed with specific substrates D-glutamate and D-alanine, whereas half-reactions with D-leucine and D-phenylalanine exhibited biphasic kinetics. All half-reactions proceeded until the complete conversion of PLP due to the release of the pyridoxamine-5'-phosphate form of cofactor from the holoenzyme . Comparison of kinetic parameters of half-reactions and the overall transamination reactions for D-leucine, D-phenylalanine revealed the increase in the rates of deamination of these substrates in the overall reaction with α-ketoglutarate. In the overall transamination reaction, the catalytic turnover rates for D-leucine and D-phenylalanine increased by 260 and 60 times, correspondingly, comparing with the slowest step rate constants in the half-reactions. We suggested the activating effect by a specific substrate α-ketoglutarate in the overall transamination reaction. The study of half-reactions helped to quantify the specificity of DAAT from H. hydrossis for D-amino acids with different properties. The results obtained are the first detailed analysis of half-reactions catalyzed by DAAT.
Collapse
Affiliation(s)
- Alina K Bakunova
- A.N.Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russian Federation
| | - Alexey A Kostyukov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin st., 4, 119334 Moscow, Russian Federation
| | - Vladimir A Kuzmin
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin st., 4, 119334 Moscow, Russian Federation
| | - Vladimir O Popov
- A.N.Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russian Federation
| | - Ekaterina Yu Bezsudnova
- A.N.Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russian Federation.
| |
Collapse
|
4
|
Asymmetric Synthesis of Enantiomerically Pure Aliphatic and Aromatic D-Amino Acids Catalyzed by Transaminase from Haliscomenobacter hydrossis. Catalysts 2022. [DOI: 10.3390/catal12121551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
D-amino acids are valuable building blocks for the synthesis of biologically active compounds and pharmaceuticals. The asymmetric synthesis of chiral amino acids from prochiral ketones using stereoselective enzymes is a well-known but far from exhausted approach for large-scale production. Herein, we investigated a pyridoxal-5′-phosphate-dependent D-amino acid transaminase from Haliscomenobacter hydrossis as a potential biocatalyst for the enzymatic asymmetric synthesis of optically pure aliphatic and aromatic D-amino acids. We studied the catalytic efficiency and stereoselectivity of transaminase from H. hydrossis in the amination of aliphatic and aromatic α-keto acids, using D-glutamate as a source of the amino group. We constructed a one-pot three-enzyme system, which included transaminase and two auxiliary enzymes, hydroxyglutarate dehydrogenase, and glucose dehydrogenase, to produce D-amino acids with a product yield of 95–99% and an enantiomeric excess of more than 99%. We estimated the stability of the transaminase and the cofactor leakage under reaction conditions. It was found that a high concentration of α-keto acids as well as a low reaction temperature (30 °C) can reduce the cofactor leakage under reaction conditions. The obtained results demonstrated the efficiency of transaminase from H. hydrossis in the asymmetric synthesis of enantiomerically pure D-amino acids.
Collapse
|
5
|
Biocatalytic Cascade of Sebacic Acid Production with In Situ Co-Factor Regeneration Enabled by Engineering of an Alcohol Dehydrogenase. Catalysts 2022. [DOI: 10.3390/catal12111318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Sebacic acid (1,10-decanedioic acid) is an important chemical intermediate. Traditional chemical oxidation methods for sebacic acid production do not conform with “green” manufacturing. With the rapid development of enzymatic technologies, a biocatalytic cascade method based on the Baeyer–Villiger monooxygenase was developed. The most attractive point of the method is the oleic acid that can be utilized as raw material, which is abundant in nature. However, this bio-catalysis process needs co-factor electron carriers, and the high cost of the co-factor limits its progress. In this piece of work, a co-factor in situ regeneration system between ADH from Micrococcus luteus WIUJH20 (MlADH) and BVMO is proposed. Since the co-factors of both enzymes are different, switching the co-factor preference of native MlADH from NAD+ to NADP+ is necessary. Switching research was carried out based on in silico simulation, and the sites of Tyr36, Asp 37, Ala38, and Val39 were selected for mutation investigation. The experimental results demonstrated that mutants of MlADH_D37G and MlADH_D37G/A38T/V39K would utilize NADP+ efficiently, and the mutant of MlADH_D37G/A38T/V39K demonstrated the highest sebacic acid yield with the combination of BVMO. The results indicated that the in situ co-factor generation system is successfully developed, which would improve the efficiency of the biocatalytic cascade for sebacic acid production and is helpful for simplifying product isolation, thus, reducing the cost of the enzymatic transformations process.
Collapse
|
6
|
Bakunova AK, Nikolaeva AY, Rakitina TV, Isaikina TY, Khrenova MG, Boyko KM, Popov VO, Bezsudnova EY. The Uncommon Active Site of D-Amino Acid Transaminase from Haliscomenobacter hydrossis: Biochemical and Structural Insights into the New Enzyme. Molecules 2021; 26:molecules26165053. [PMID: 34443642 PMCID: PMC8401098 DOI: 10.3390/molecules26165053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 02/02/2023] Open
Abstract
Among industrially important pyridoxal-5’-phosphate (PLP)-dependent transaminases of fold type IV D-amino acid transaminases are the least studied. However, the development of cascade enzymatic processes, including the synthesis of D-amino acids, renewed interest in their study. Here, we describe the identification, biochemical and structural characterization of a new D-amino acid transaminase from Haliscomenobacter hydrossis (Halhy). The new enzyme is strictly specific towards D-amino acids and their keto analogs; it demonstrates one of the highest rates of transamination between D-glutamate and pyruvate. We obtained the crystal structure of the Halhy in the holo form with the protonated Schiff base formed by the K143 and the PLP. Structural analysis revealed a novel set of the active site residues that differ from the key residues forming the active sites of the previously studied D-amino acids transaminases. The active site of Halhy includes three arginine residues, one of which is unique among studied transaminases. We identified critical residues for the Halhy catalytic activity and suggested functions of the arginine residues based on the comparative structural analysis, mutagenesis, and molecular modeling simulations. We suggested a strong positive charge in the O-pocket and the unshaped P-pocket as a structural code for the D-amino acid specificity among transaminases of PLP fold type IV. Characteristics of Halhy complement our knowledge of the structural basis of substrate specificity of D-amino acid transaminases and the sequence-structure-function relationships in these enzymes.
Collapse
Affiliation(s)
- Alina K. Bakunova
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
| | - Alena Yu. Nikolaeva
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
| | - Tatiana V. Rakitina
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
- Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Miklukho-Maklaya Str. 16/10, 117997 Moscow, Russia
| | - Tatiana Y. Isaikina
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
| | - Maria G. Khrenova
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
- Chemistry Department, Lomonosov Moscow State University, Leninskiye Gory 1/3, 119991 Moscow, Russia
| | - Konstantin M. Boyko
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
| | - Vladimir O. Popov
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
| | - Ekaterina Yu. Bezsudnova
- Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Ave. 33, bld. 2, 119071 Moscow, Russia; (A.K.B.); (A.Y.N.); (T.V.R.); (T.Y.I.); (M.G.K.); (K.M.B.); (V.O.P.)
- Correspondence: author E-mail:
| |
Collapse
|
7
|
Lu C, Zhang S, Song W, Liu J, Chen X, Liu L, Wu J. Efficient Synthesis of D‐Phenylalanine from L‐Phenylalanine via a Tri‐Enzymatic Cascade Pathway. ChemCatChem 2021. [DOI: 10.1002/cctc.202100237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Cui Lu
- School of Pharmaceutical Science Jiangnan University Wuxi 214122 (P. R. China
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi 214122 (P. R. China
| | - Sheng Zhang
- Tianrui Chemical Co.,Ltd Department of Chemistry Quzhou 324400 (P. R. China
| | - Wei Song
- School of Pharmaceutical Science Jiangnan University Wuxi 214122 (P. R. China
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi 214122 (P. R. China
| | - Jia Liu
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi 214122 (P. R. China
| | - Xiulai Chen
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi 214122 (P. R. China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology Jiangnan University Wuxi 214122 (P. R. China
| | - Jing Wu
- School of Pharmaceutical Science Jiangnan University Wuxi 214122 (P. R. China
| |
Collapse
|
8
|
Pickl M, Marín-Valls R, Joglar J, Bujons J, Clapés P. Chemoenzymatic Production of Enantiocomplementary 2-Substituted 3-Hydroxycarboxylic Acids from L-α-Amino Acids. Adv Synth Catal 2021; 363:2866-2876. [PMID: 34276272 PMCID: PMC7611260 DOI: 10.1002/adsc.202100145] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Indexed: 12/14/2022]
Abstract
A two-enzyme cascade reaction plus in situ oxidative decarboxylation for the transformation of readily available canonical and non-canonical L-α-amino acids into 2-substituted 3-hydroxy-carboxylic acid derivatives is described. The biocatalytic cascade consisted of an oxidative deamination of L-α-amino acids by an L-α-amino acid deaminase from Cosenzaea myxofaciens, rendering 2-oxoacid intermediates, with an ensuing aldol addition reaction to formaldehyde, catalyzed by metal-dependent (R)- or (S)-selective carboligases namely 2-oxo-3-deoxy-l-rhamnonate aldolase (YfaU) and ketopantoate hydroxymethyltransferase (KPHMT), respectively, furnishing 3-substituted 4-hydroxy-2-oxoacids. The overall substrate conversion was optimized by balancing biocatalyst loading and amino acid and formaldehyde concentrations, yielding 36-98% aldol adduct formation and 91- 98% ee for each enantiomer. Subsequent in situ follow-up chemistry via hydrogen peroxide-driven oxidative decarboxylation afforded the corresponding 2-substituted 3-hydroxycarboxylic acid derivatives.
Collapse
Affiliation(s)
- Mathias Pickl
- Department of Chemical Biology. Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18–26, 08034 Barcelona, Spain
- Department of Chemistry, University of Graz, Heinrichstrasse 28, 8010 Graz, Austria
| | - Roser Marín-Valls
- Department of Chemical Biology. Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18–26, 08034 Barcelona, Spain
| | - Jesús Joglar
- Department of Chemical Biology. Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18–26, 08034 Barcelona, Spain
| | - Jordi Bujons
- Department of Chemical Biology. Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18–26, 08034 Barcelona, Spain
| | - Pere Clapés
- Department of Chemical Biology. Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18–26, 08034 Barcelona, Spain
| |
Collapse
|
9
|
Slagman S, Fessner WD. Biocatalytic routes to anti-viral agents and their synthetic intermediates. Chem Soc Rev 2021; 50:1968-2009. [DOI: 10.1039/d0cs00763c] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
An assessment of biocatalytic strategies for the synthesis of anti-viral agents, offering guidelines for the development of sustainable production methods for a future COVID-19 remedy.
Collapse
Affiliation(s)
- Sjoerd Slagman
- Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- Germany
| | - Wolf-Dieter Fessner
- Institut für Organische Chemie und Biochemie
- Technische Universität Darmstadt
- Germany
| |
Collapse
|
10
|
Zhang M, Hu P, Zheng YC, Zeng BB, Chen Q, Zhang ZJ, Xu JH. Structure-guided engineering of Pseudomonas dacunhael-aspartate β-decarboxylase for l-homophenylalanine synthesis. Chem Commun (Camb) 2020; 56:13876-13879. [PMID: 33094304 DOI: 10.1039/d0cc05871h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Structure-guided engineering of Pseudomonas dacunhael-aspartate β-decarboxylase (AspBDC) resulted in a double mutant (R37A/T382G) with remarkable 15 400-fold improvement in specific activity reaching 216 mU mg-1, towards the target substrate 3(R)-benzyl-l-aspartate. A novel strategy for enzymatic synthesis of l-homophenylalanine was developed by using the variant as a biocatalyst affording 75% product yield within 12 h. Our results underscore the potential of engineered AspBDC for the biocatalytic synthesis of pharmaceutically relevant and value added unnatural l-amino acids.
Collapse
Affiliation(s)
- Min Zhang
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Centre for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China.
| | | | | | | | | | | | | |
Collapse
|