1
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Lv K, Cao X, Pedroso MM, Wu B, Li J, He B, Schenk G. Structure-guided engineering of branched-chain α-keto acid decarboxylase for improved 1,2,4-butanetriol production by in vitro synthetic enzymatic biosystem. Int J Biol Macromol 2024; 255:128303. [PMID: 37992939 DOI: 10.1016/j.ijbiomac.2023.128303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 11/07/2023] [Accepted: 11/19/2023] [Indexed: 11/24/2023]
Abstract
Efficient synthetic routes for biomanufacturing chemicals often require the overcoming of pathway bottlenecks by tailoring enzymes to improve the catalytic efficiency or even implement non-native activities. 1,2,4-butanetriol (BTO), a valuable commodity chemical, is currently biosynthesized from D-xylose via a four-enzyme reaction cascade, with the ThDP-dependent α-keto acid decarboxylase (KdcA) identified as the potential bottleneck. Here, to further enhance the catalytic activity of KdcA toward the non-native substrate α-keto-3-deoxy-xylonate (KDX), in silico screening and structure-guided evolution were performed. The best mutants, S286L/G402P and V461K, exhibited a 1.8- and 2.5-fold higher enzymatic activity in the conversion of KDX to 3,4-dihydroxybutanal when compared to KdcA, respectively. MD simulations revealed that the two sets of mutations reshaped the substrate binding pocket, thereby increasing the binding affinity for KDX and promoting interactions between KDX and cofactor ThDP. Then, when the V461K mutant instead of wild type KdcA was integrated into the enzyme cascade, a 1.9-fold increase in BTO titer was observed. After optimization of the reaction conditions, the enzyme cocktail contained V461K converted 60 g/L D-xylose to 22.1 g/L BTO with a yield of 52.1 %. This work illustrated that protein engineering is a powerful tool for modifying the output of metabolic pathway.
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Affiliation(s)
- Kemin Lv
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Xuefei Cao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Marcelo Monteiro Pedroso
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, Australia
| | - Bin Wu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.
| | - Jiahuang Li
- School of Biopharmacy, China Pharmaceutical University, Nanjing, China.
| | - Bingfang He
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, China
| | - Gerhard Schenk
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Brisbane, Australia
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2
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Li ZM, Hu Z, Wang X, Chen S, Yu W, Liu J, Li Z. Biochemical and Structural Insights into a Thiamine Diphosphate-Dependent α-Ketoglutarate Decarboxylase from Cyanobacterium Microcystis aeruginosa NIES-843. Int J Mol Sci 2023; 24:12198. [PMID: 37569577 PMCID: PMC10418658 DOI: 10.3390/ijms241512198] [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: 06/28/2023] [Revised: 07/26/2023] [Accepted: 07/29/2023] [Indexed: 08/13/2023] Open
Abstract
α-Ketoglutarate decarboxylase is a crucial enzyme in the tricarboxylic acid cycle of cyanobacteria, catalyzing the non-oxidative decarboxylation of α-ketoglutarate to produce succinate semialdehyde and CO2. The decarboxylation process is reliant on the cofactor of thiamine diphosphate. However, this enzyme's biochemical and structural properties have not been well characterized. In this work, two α-ketoglutarate decarboxylases encoded by MAE_06010 and MiAbw_01735 genes from Microcystis aeruginosa NIES-843 (MaKGD) and NIES-4325 (MiKGD), respectively, were overexpressed and purified by using an Escherichia coli expression system. It was found that MaKGD exhibited 9.2-fold higher catalytic efficiency than MiKGD, which may be attributed to the absence of glutamate decarboxylase in Microcystis aeruginosa NIES-843. Further biochemical investigation of MaKGD demonstrated that it displayed optimum activity at pH 6.5-7.0 and was most activated by Mg2+. Additionally, MaKGD showed substrate specificity towards α-ketoglutarate. Structural modeling and autodocking results revealed that the active site of MaKGD contained a distinct binding pocket where α-ketoglutarate and thiamine diphosphate interacted with specific amino acid residues via hydrophobic interactions, hydrogen bonds and salt bridges. Furthermore, the mutagenesis study provided strong evidence supporting the importance of certain residues in the catalysis of MaKGD. These findings provide new insights into the structure-function relationships of α-ketoglutarate decarboxylases from cyanobacteria.
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Affiliation(s)
- Zhi-Min Li
- College of Chemistry and Materials, Jiangxi Agricultural University, Nanchang 330045, China;
| | - Ziwei Hu
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Xiaoqin Wang
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Suhang Chen
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Weiyan Yu
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Jianping Liu
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Zhimin Li
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
- Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables in Jiangxi Province, Jiangxi Agricultural University, Nanchang 330045, China
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Yukawa T, Bamba T, Matsuda M, Yoshida T, Inokuma K, Kim J, Won Lee J, Jin YS, Kondo A, Hasunuma T. Enhanced production of 3,4-dihydroxybutyrate from xylose by engineered yeast via xylonate re-assimilation under alkaline condition. Biotechnol Bioeng 2023; 120:511-523. [PMID: 36321324 DOI: 10.1002/bit.28278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 09/27/2022] [Accepted: 10/28/2022] [Indexed: 11/07/2022]
Abstract
To realize lignocellulose-based bioeconomy, efficient conversion of xylose into valuable chemicals by microbes is necessary. Xylose oxidative pathways that oxidize xylose into xylonate can be more advantageous than conventional xylose assimilation pathways because of fewer reaction steps without loss of carbon and ATP. Moreover, commodity chemicals like 3,4-dihydroxybutyrate and 3-hydroxybutyrolactone can be produced from the intermediates of xylose oxidative pathway. However, successful implementations of xylose oxidative pathway in yeast have been hindered because of the secretion and accumulation of xylonate which is a key intermediate of the pathway, leading to low yield of target product. Here, high-yield production of 3,4-dihydroxybutyrate from xylose by engineered yeast was achieved through genetic and environmental perturbations. Specifically, 3,4-dihydroxybutyrate biosynthetic pathway was established in yeast through deletion of ADH6 and overexpression of yneI. Also, inspired by the mismatch of pH between host strain and key enzyme of XylD, alkaline fermentations (pH ≥ 7.0) were performed to minimize xylonate accumulation. Under the alkaline conditions, xylonate was re-assimilated by engineered yeast and combined product yields of 3,4-dihydroxybutyrate and 3-hydroxybutyrolactone resulted in 0.791 mol/mol-xylose, which is highest compared with previous study. These results shed light on the utility of the xylose oxidative pathway in yeast.
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Affiliation(s)
- Takahiro Yukawa
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Takahiro Bamba
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Mami Matsuda
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Takanobu Yoshida
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Kentaro Inokuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Jungyeon Kim
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Jae Won Lee
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan.,RIKEN Center for Sustainable Resource Science, Kanagawa, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan.,RIKEN Center for Sustainable Resource Science, Kanagawa, Japan
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Frazão CJR, Trichez D, Serrano-Bataille H, Dagkesamanskaia A, Topham CM, Walther T, François JM. Construction of a synthetic pathway for the production of 1,3-propanediol from glucose. Sci Rep 2019; 9:11576. [PMID: 31399628 PMCID: PMC6689062 DOI: 10.1038/s41598-019-48091-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 07/25/2019] [Indexed: 11/09/2022] Open
Abstract
In this work, we describe the construction of a synthetic metabolic pathway enabling direct biosynthesis of 1,3-propanediol (PDO) from glucose via the Krebs cycle intermediate malate. This non-natural pathway extends a previously published synthetic pathway for the synthesis of (L)-2,4-dihydroxybutyrate (L-DHB) from malate by three additional reaction steps catalyzed respectively, by a DHB dehydrogenase, a 2-keto-4-hydroxybutyrate (OHB) dehydrogenase and a PDO oxidoreductase. Screening and structure-guided protein engineering provided a (L)-DHB dehydrogenase from the membrane-associated (L)-lactate dehydrogenase of E. coli and OHB decarboxylase variants derived from the branched-chain keto-acid decarboxylase encoded by kdcA from Lactococcus lactis or pyruvate decarboxylase from Zymomonas mobilis. The simultaneous overexpression of the genes encoding these enzymes together with the endogenous ydhD-encoded aldehyde reductase enabled PDO biosynthesis from (L)-DHB. While the simultaneous expression of the six enzymatic activities in a single engineered E. coli strain resulted in a low production of 0.1 mM PDO from 110 mM glucose, a 40-fold increased PDO titer was obtained by co-cultivation of an E. coli strain expressing the malate-DHB pathway with another strain harboring the DHB-to-PDO pathway.
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Affiliation(s)
- Cláudio J R Frazão
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | - Débora Trichez
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | - Hélène Serrano-Bataille
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | - Adilia Dagkesamanskaia
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France
| | | | - Thomas Walther
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France.,TWB, 3 Rue des Satellites, Canal Biotech Building 2, F-31400, Toulouse, France.,TU Dresden, Institute of Natural Materials Technology, 01062, Dresden, Germany
| | - Jean Marie François
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA, 135 Avenue de Rangueil, F-31077, Toulouse, France. .,TWB, 3 Rue des Satellites, Canal Biotech Building 2, F-31400, Toulouse, France.
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5
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Germer P, Gauchenova E, Walter L, Müller M. Thiamine Diphosphate Dependent KdcA‐Catalysed Formyl Elongation of Aldehydes. ChemCatChem 2019. [DOI: 10.1002/cctc.201900712] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Philipp Germer
- Institut für Pharmazeutische WissenschaftenAlbert-Ludwigs-Universität Freiburg Albertstrasse 25 Freiburg 79104 Germany
| | - Ekaterina Gauchenova
- Institut für Pharmazeutische WissenschaftenAlbert-Ludwigs-Universität Freiburg Albertstrasse 25 Freiburg 79104 Germany
| | - Lydia Walter
- Institut für Pharmazeutische WissenschaftenAlbert-Ludwigs-Universität Freiburg Albertstrasse 25 Freiburg 79104 Germany
| | - Michael Müller
- Institut für Pharmazeutische WissenschaftenAlbert-Ludwigs-Universität Freiburg Albertstrasse 25 Freiburg 79104 Germany
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6
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Mohammadi Nargesi B, Sprenger GA, Youn JW. Metabolic Engineering of Escherichia coli for para-Amino-Phenylethanol and para-Amino-Phenylacetic Acid Biosynthesis. Front Bioeng Biotechnol 2019; 6:201. [PMID: 30662895 PMCID: PMC6328984 DOI: 10.3389/fbioe.2018.00201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 12/10/2018] [Indexed: 11/24/2022] Open
Abstract
Aromatic amines are an important class of chemicals which are used as building blocks for the synthesis of polymers and pharmaceuticals. In this study we establish a de novo pathway for the biosynthesis of the aromatic amines para-amino-phenylethanol (PAPE) and para-amino-phenylacetic acid (4-APA) in Escherichia coli. We combined a synthetic para-amino-l-phenylalanine pathway with the fungal Ehrlich pathway. Therefore, we overexpressed the heterologous genes encoding 4-amino-4-deoxychorismate synthase (pabAB from Corynebacterium glutamicum), 4-amino-4-deoxychorismate mutase and 4-amino-4-deoxyprephenate dehydrogenase (papB and papC from Streptomyces venezuelae) and ThDP-dependent keto-acid decarboxylase (aro10 from Saccharomyces cerevisiae) in E. coli. The resulting para-amino-phenylacetaldehyde either was reduced to PAPE or oxidized to 4-APA. The wild type strain E. coli LJ110 with a plasmid carrying these four genes produced (in shake flask cultures) 11 ± 1.5 mg l−1 of PAPE from glucose (4.5 g l−1). By the additional cloning and expression of feaB (phenylacetaldehyde dehydrogenase from E. coli) 36 ± 5 mg l−1 of 4-APA were obtained from 4.5 g l−1 glucose. Competing reactions, such as the genes for aminotransferases (aspC and tyrB) or for biosynthesis of L-phenylalanine and L-tyrosine (pheA, tyrA) and for the regulator TyrR were removed. Additionally, the E. coli genes aroFBL were cloned and expressed from a second plasmid. The best producer strains of E. coli showed improved formation of PAPE and 4-APA, respectively. Plasmid-borne expression of an aldehyde reductase (yahK from E. coli) gave best values for PAPE production, whereas feaB-overexpression led to best values for 4-APA. In fed-batch cultivation, the best producer strains achieved 2.5 ± 0.15 g l−1 of PAPE from glucose (11% C mol mol-1 glucose) and 3.4 ± 0.3 g l−1 of 4-APA (17% C mol mol−1 glucose), respectively which are the highest values for recombinant strains reported so far.
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7
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Sutiono S, Carsten J, Sieber V. Structure-Guided Engineering of α-Keto Acid Decarboxylase for the Production of Higher Alcohols at Elevated Temperature. CHEMSUSCHEM 2018; 11:3335-3344. [PMID: 29953730 DOI: 10.1002/cssc.201800944] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Branched-chain keto acid decarboxylases (KDCs) are a class of enzymes that catalyze the decarboxylation of α-keto acids. They are key enzymes for production of higher alcohols in vivo and in vitro. However, the two most active KDCs (KivD and KdcA) have only moderate thermostability (<55 °C), which hinders the production of alcohols at high temperatures. Herein, structure-guided engineering toward improved thermostability of KdcA is outlined. Strategies such as stabilization of the catalytic center, surface engineering, and optimization of dimer interactions were applied. With seven amino acid substitutions, variant 7M.D showed an increase of the temperature at which 50 % of activity remains after one-hour incubation T1h50 by 14.8 °C without compromising its substrate specificity. 7M.D exhibited greater than 400-fold improvement of half-life at 70 °C and greater than 600-fold increase in process stability in the presence of 4 % isobutanol at 50 °C. 7M.D is more promising for the production of higher alcohols in thermophiles (>65 °C) and in cell-free applications.
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Affiliation(s)
- Samuel Sutiono
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany
| | - Jörg Carsten
- Catalytic Research Center, Technical University of Munich, Ernst-Otto-Fischer-Straße 1, 85748, Garching, Germany
| | - Volker Sieber
- Chair of Chemistry of Biogenic Resources, TUM Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Schulgasse 16, 94315, Straubing, Germany
- Catalytic Research Center, Technical University of Munich, Ernst-Otto-Fischer-Straße 1, 85748, Garching, Germany
- Straubing Branch BioCat, Fraunhofer IGB, Schulgasse 11a, 94315, Straubing, Germany
- School of Chemistry and Molecular Biosciences, The University of Queensland, 68 Copper Road, St., Lucia, 4072, Australia
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8
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Expression and biochemical characterization of α-ketoglutarate decarboxylase from cyanobacterium Synechococcus sp. PCC7002. Int J Biol Macromol 2018; 114:188-193. [PMID: 29574001 DOI: 10.1016/j.ijbiomac.2018.03.112] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/19/2018] [Accepted: 03/21/2018] [Indexed: 11/22/2022]
Abstract
α-Ketoglutarate decarboxylase (α-KGD), one member of α-keto acid decarboxylases, catalyzing non-oxidative decarboxylation of α-ketoglutarate to form succinic semialdehyde, was proposed to play critical role in completing tricarboxylic acid (TCA) cycle of cyanobacteria. Although the catalytic function of α-KGD from Synechococcus sp. PCC7002 was demonstrated previously, there was no detailed biochemical characterization of α-KGD from Synechococcus sp. PCC7002 yet. In this study, the gene encoding α-KGD from Synechococcus sp. PCC7002 was amplified and soluble expression of recombinant α-KGD was achieved by coexpressing with pTf16 chaperone plasmid in E. coli BL21 (DE3). Kinetic analysis showed that the activity of α-KGD was dependent on cofactors of thiamine pyrophosphate and divalent cation. Meanwhile this α-KGD was specific for α-ketoglutarate with respect to the decarboxylation activity despite of the pretty low activity of acetolactate synthase. The catalytic efficiency of α-KGD (the values of kcat and kcat/Km for α-ketoglutarate were 1.2s-1 and 6.3×103M-1s-1, respectively) might provide evidence for its physiological role in TCA cycle of Synechococcus sp. PCC7002.
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Miao R, Xie H, M Ho F, Lindblad P. Protein engineering of α-ketoisovalerate decarboxylase for improved isobutanol production in Synechocystis PCC 6803. Metab Eng 2018; 47:42-48. [PMID: 29501927 DOI: 10.1016/j.ymben.2018.02.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 01/12/2018] [Accepted: 02/25/2018] [Indexed: 12/13/2022]
Abstract
Protein engineering is a powerful tool to modify e.g. protein stability, activity and substrate selectivity. Heterologous expression of the enzyme α-ketoisovalerate decarboxylase (Kivd) in the unicellular cyanobacterium Synechocystis PCC 6803 results in cells producing isobutanol and 3-methyl-1-butanol, with Kivd identified as a potential bottleneck. In the present study, we used protein engineering of Kivd to improve isobutanol production in Synechocystis PCC 6803. Isobutanol is a flammable compound that can be used as a biofuel due to its high energy density and suitable physical and chemical properties. Single replacement, either Val461 to isoleucine or Ser286 to threonine, increased the Kivd activity significantly, both in vivo and in vitro resulting in increased overall production while isobutanol production was increased more than 3-methyl-1-butanol production. Moreover, among all the engineered strains examined, the strain with the combined modification V461I/S286T showed the highest (2.4 times) improvement of isobutanol-to-3M1B molar ratio, which was due to a decrease of the activity towards 3M1B production. Protein engineering of Kivd resulted in both enhanced total catalytic activity and preferential shift towards isobutanol production in Synechocystis PCC 6803.
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Affiliation(s)
- Rui Miao
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-751 20 Uppsala, Sweden.
| | - Hao Xie
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-751 20 Uppsala, Sweden.
| | - Felix M Ho
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-751 20 Uppsala, Sweden.
| | - Peter Lindblad
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Box 523, SE-751 20 Uppsala, Sweden.
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10
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Wang X, Lei G, Wu X, Wang F, Lai C, Li Z. Expression, purification and characterization of sll1981 protein from cyanobacterium Synechocystis sp. PCC6803. Protein Expr Purif 2017; 139:21-28. [DOI: 10.1016/j.pep.2017.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 06/14/2017] [Accepted: 07/17/2017] [Indexed: 11/26/2022]
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11
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Wang B, Bai Y, Fan T, Zheng X, Cai Y. Characterisation of a thiamine diphosphate-dependent alpha-keto acid decarboxylase from Proteus mirabilis JN458. Food Chem 2017; 232:19-24. [DOI: 10.1016/j.foodchem.2017.03.164] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 03/20/2017] [Accepted: 03/29/2017] [Indexed: 11/16/2022]
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12
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Saturated mutagenesis of ketoisovalerate decarboxylase V461 enabled specific synthesis of 1-pentanol via the ketoacid elongation cycle. Sci Rep 2017; 7:11284. [PMID: 28900255 PMCID: PMC5595793 DOI: 10.1038/s41598-017-11624-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 08/25/2017] [Indexed: 11/25/2022] Open
Abstract
Iterative ketoacid elongation has been an essential tool in engineering artificial metabolism, in particular the synthetic alcohols. However, precise control of product specificity is still greatly challenged by the substrate promiscuity of the ketoacid decarboxylase, which unselectively hijacks ketoacid intermediates from the elongation cycle along with the target ketoacid. In this work, preferential tuning of the Lactococcus lactis ketoisovalerate decarboxylase (Kivd) specificity toward 1-pentanol synthesis was achieved via saturated mutagenesis of the key residue V461 followed by screening of the resulting alcohol spectrum. Substitution of V461 with the small and polar amino acid glycine or serine significantly improved the Kivd selectivity toward the 1-pentanol precursor 2-ketocaproate by lowering its catalytic efficiency for the upstream ketoacid 2-ketobutyrate and 2-ketovalerate. Conversely, replacing V461 with bulky or charged side chains displayed severely adverse effect. Increasing supply of the iterative addition unit acetyl-CoA by acetate feeding further drove 2-ketoacid flux into the elongation cycle and enhanced 1-pentanol productivity. The Kivd V461G variant enabled a 1-pentanol production specificity around 90% of the total alcohol content with or without oleyl alcohol extraction. This work adds insight to the selectivity of Kivd active site.
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13
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Regio- and Stereoselective Aliphatic-Aromatic Cross-Benzoin Reaction: Enzymatic Divergent Catalysis. Chemistry 2016; 22:13999-14005. [DOI: 10.1002/chem.201602084] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Indexed: 11/07/2022]
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14
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Andrews FH, Horton JD, Shin D, Yoon HJ, Logsdon MG, Malik AM, Rogers MP, Kneen MM, Suh SW, McLeish MJ. The kinetic characterization and X-ray structure of a putative benzoylformate decarboxylase from M. smegmatis highlights the difficulties in the functional annotation of ThDP-dependent enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:1001-9. [DOI: 10.1016/j.bbapap.2015.04.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 04/05/2015] [Accepted: 04/23/2015] [Indexed: 10/23/2022]
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15
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Kourist R, Guterl JK, Miyamoto K, Sieber V. Enzymatic Decarboxylation-An Emerging Reaction for Chemicals Production from Renewable Resources. ChemCatChem 2014. [DOI: 10.1002/cctc.201300881] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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16
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Andrews FH, McLeish MJ. Using site-saturation mutagenesis to explore mechanism and substrate specificity in thiamin diphosphate-dependent enzymes. FEBS J 2013; 280:6395-411. [DOI: 10.1111/febs.12459] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 07/23/2013] [Accepted: 07/26/2013] [Indexed: 12/25/2022]
Affiliation(s)
- Forest H. Andrews
- Department of Chemistry and Chemical Biology; Indiana University-Purdue University Indianapolis; IN USA
| | - Michael J. McLeish
- Department of Chemistry and Chemical Biology; Indiana University-Purdue University Indianapolis; IN USA
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17
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Wei J, Timler JG, Knutson CM, Barney BM. Branched-chain 2-keto acid decarboxylases derived from Psychrobacter. FEMS Microbiol Lett 2013; 346:105-12. [PMID: 23826991 DOI: 10.1111/1574-6968.12208] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 06/27/2013] [Accepted: 06/28/2013] [Indexed: 11/27/2022] Open
Abstract
The conversion of branched-chain amino acids to branched-chain acids or alcohols is an important aspect of flavor in the food industry and is dependent on the Ehrlich pathway found in certain lactic acid bacteria. A key enzyme in the pathway, the 2-keto acid decarboxylase (KDC), is also of interest in biotechnology applications to produce small branched-chain alcohols that might serve as improved biofuels or other commodity feedstocks. This enzyme has been extensively studied in the model bacterium Lactococcus lactis, but is also found in other bacteria and higher organisms. In this report, distinct homologs of the L. lactis KDC originally annotated as pyruvate decarboxylases from Psychrobacter cryohalolentis K5 and P. arcticus 273-4 were cloned and characterized, confirming a related activity toward specific branched-chain 2-keto acids derived from branched-chain amino acids. Further, KDC activity was confirmed in intact cells and cell-free extracts of P. cryohalolentis K5 grown on both rich and defined media, indicating that the Ehrlich pathway may also be utilized in some psychrotrophs and psychrophiles. A comparison of the similarities and differences in the P. cryohalolentis K5 and P. arcticus 273-4 KDC activities to other bacterial KDCs is presented.
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Affiliation(s)
- Jiashi Wei
- Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN, USA; Biotechnology Institute, University of Minnesota, St. Paul, MN, USA
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18
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Yamamoto S, Suda M, Niimi S, Inui M, Yukawa H. Strain optimization for efficient isobutanol production usingCorynebacterium glutamicumunder oxygen deprivation. Biotechnol Bioeng 2013; 110:2938-48. [DOI: 10.1002/bit.24961] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 04/18/2013] [Accepted: 05/08/2013] [Indexed: 01/20/2023]
Affiliation(s)
- Shogo Yamamoto
- Research Institute of Innovative Technology for the Earth (RITE); 9-2, Kizugawadai Kizugawa Kyoto 619-0292 Japan
| | - Masako Suda
- Research Institute of Innovative Technology for the Earth (RITE); 9-2, Kizugawadai Kizugawa Kyoto 619-0292 Japan
| | - Satoko Niimi
- Research Institute of Innovative Technology for the Earth (RITE); 9-2, Kizugawadai Kizugawa Kyoto 619-0292 Japan
| | - Masayuki Inui
- Research Institute of Innovative Technology for the Earth (RITE); 9-2, Kizugawadai Kizugawa Kyoto 619-0292 Japan
| | - Hideaki Yukawa
- Research Institute of Innovative Technology for the Earth (RITE); 9-2, Kizugawadai Kizugawa Kyoto 619-0292 Japan
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19
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Rabinovitch-Deere CA, Oliver JWK, Rodriguez GM, Atsumi S. Synthetic biology and metabolic engineering approaches to produce biofuels. Chem Rev 2013; 113:4611-32. [PMID: 23488968 DOI: 10.1021/cr300361t] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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20
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Lee WH, Seo SO, Bae YH, Nan H, Jin YS, Seo JH. Isobutanol production in engineered Saccharomyces cerevisiae by overexpression of 2-ketoisovalerate decarboxylase and valine biosynthetic enzymes. Bioprocess Biosyst Eng 2012; 35:1467-75. [DOI: 10.1007/s00449-012-0736-y] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 04/08/2012] [Indexed: 11/30/2022]
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21
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Xiong M, Deng J, Woodruff AP, Zhu M, Zhou J, Park SW, Li H, Fu Y, Zhang K. A bio-catalytic approach to aliphatic ketones. Sci Rep 2012; 2:311. [PMID: 22416247 PMCID: PMC3301443 DOI: 10.1038/srep00311] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 02/25/2012] [Indexed: 11/30/2022] Open
Abstract
Depleting oil reserves and growing environmental concerns have necessitated the development of sustainable processes to fuels and chemicals. Here we have developed a general metabolic platform in E. coli to biosynthesize carboxylic acids. By engineering selectivity of 2-ketoacid decarboxylases and screening for promiscuous aldehyde dehydrogenases, synthetic pathways were constructed to produce both C5 and C6 acids. In particular, the production of isovaleric acid reached 32 g/L (0.22 g/g glucose yield), which is 58% of the theoretical yield. Furthermore, we have developed solid base catalysts to efficiently ketonize the bio-derived carboxylic acids such as isovaleric acid and isocaproic acid into high volume industrial ketones: methyl isobutyl ketone (MIBK, yield 84%), diisobutyl ketone (DIBK, yield 66%) and methyl isoamyl ketone (MIAK, yield 81%). This hybrid “Bio-Catalytic conversion” approach provides a general strategy to manufacture aliphatic ketones, and represents an alternate route to expanding the repertoire of renewable chemicals.
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Affiliation(s)
- Mingyong Xiong
- Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Minnesota 55455, USA
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22
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Substrate specificity in thiamin diphosphate-dependent decarboxylases. Bioorg Chem 2011; 43:26-36. [PMID: 22245019 DOI: 10.1016/j.bioorg.2011.12.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 12/19/2011] [Accepted: 12/20/2011] [Indexed: 11/20/2022]
Abstract
Thiamin diphosphate (ThDP) is the biologically active form of vitamin B(1), and ThDP-dependent enzymes are found in all forms of life. The catalytic mechanism of this family requires the formation of a common intermediate, the 2α-carbanion-enamine, regardless of whether the enzyme is involved in C-C bond formation or breakdown, or even formation of C-N, C-O and C-S bonds. This demands that the enzymes must screen substrates prior to, and/or after, formation of the common intermediate. This review is focused on the group for which the second step is the protonation of the 2α-carbanion, i.e., the ThDP-dependent decarboxylases. Based on kinetic data, sequence/structure alignments and mutagenesis studies the factors involved in substrate specificity have been identified.
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23
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Kneen MM, Stan R, Yep A, Tyler RP, Saehuan C, McLeish MJ. Characterization of a thiamin diphosphate-dependent phenylpyruvate decarboxylase from Saccharomyces cerevisiae. FEBS J 2011; 278:1842-53. [DOI: 10.1111/j.1742-4658.2011.08103.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Use of the valine biosynthetic pathway to convert glucose into isobutanol. J Ind Microbiol Biotechnol 2010; 38:1287-94. [DOI: 10.1007/s10295-010-0907-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
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25
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Gocke D, Graf T, Brosi H, Frindi-Wosch I, Walter L, Müller M, Pohl M. Comparative characterisation of thiamin diphosphate-dependent decarboxylases. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcatb.2009.03.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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Yep A, McLeish MJ. Engineering the Substrate Binding Site of Benzoylformate Decarboxylase. Biochemistry 2009; 48:8387-95. [DOI: 10.1021/bi9008402] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alejandra Yep
- College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Michael J. McLeish
- College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
- Department of Chemistry and Chemical Biology, IUPUI, Indianapolis, Indiana 46202
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27
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Brandt GS, Kneen MM, Chakraborty S, Baykal AT, Nemeria N, Yep A, Ruby DI, Petsko GA, Kenyon GL, McLeish MJ, Jordan F, Ringe D. Snapshot of a reaction intermediate: analysis of benzoylformate decarboxylase in complex with a benzoylphosphonate inhibitor. Biochemistry 2009; 48:3247-57. [PMID: 19320438 DOI: 10.1021/bi801950k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Benzoylformate decarboxylase (BFDC) is a thiamin diphosphate- (ThDP-) dependent enzyme acting on aromatic substrates. In addition to its metabolic role in the mandelate pathway, BFDC shows broad substrate specificity coupled with tight stereo control in the carbon-carbon bond-forming reverse reaction, making it a useful biocatalyst for the production of chiral alpha-hydroxy ketones. The reaction of methyl benzoylphosphonate (MBP), an analogue of the natural substrate benzoylformate, with BFDC results in the formation of a stable analogue (C2alpha-phosphonomandelyl-ThDP) of the covalent ThDP-substrate adduct C2alpha-mandelyl-ThDP. Formation of the stable adduct is confirmed both by formation of a circular dichroism band characteristic of the 1',4'-iminopyrimidine tautomeric form of ThDP (commonly observed when ThDP forms tetrahedral complexes with its substrates) and by high-resolution mass spectrometry of the reaction mixture. In addition, the structure of BFDC with the MBP inhibitor was solved by X-ray crystallography to a spatial resolution of 1.37 A (PDB ID 3FSJ). The electron density clearly shows formation of a tetrahedral adduct between the C2 atom of ThDP and the carbonyl carbon atom of the MBP. This adduct resembles the intermediate from the penultimate step of the carboligation reaction between benzaldehyde and acetaldehyde. The combination of real-time kinetic information via stopped-flow circular dichroism with steady-state data from equilibrium circular dichroism measurements and X-ray crystallography reveals details of the first step of the reaction catalyzed by BFDC. The MBP-ThDP adduct on BFDC is compared to the recently solved structure of the same adduct on benzaldehyde lyase, another ThDP-dependent enzyme capable of catalyzing aldehyde condensation with high stereospecificity.
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Affiliation(s)
- Gabriel S Brandt
- Department of Chemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454, USA
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28
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Wang PF, Yep A, Kenyon GL, McLeish MJ. Using directed evolution to probe the substrate specificity of mandelamide hydrolase. Protein Eng Des Sel 2008; 22:103-10. [DOI: 10.1093/protein/gzn073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Smit BA, Engels WJM, Smit G. Branched chain aldehydes: production and breakdown pathways and relevance for flavour in foods. Appl Microbiol Biotechnol 2008; 81:987-99. [PMID: 19015847 PMCID: PMC7419363 DOI: 10.1007/s00253-008-1758-x] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 10/16/2008] [Accepted: 10/18/2008] [Indexed: 11/28/2022]
Abstract
Branched aldehydes, such as 2-methyl propanal and 2- and 3-methyl butanal, are important flavour compounds in many food products, both fermented and non-fermented (heat-treated) products. The production and degradation of these aldehydes from amino acids is described and reviewed extensively in literature. This paper reviews aspects influencing the formation of these aldehydes at the level of metabolic conversions, microbial and food composition. Special emphasis was on 3-methyl butanal and its presence in various food products. Knowledge gained about the generation pathways of these flavour compounds is essential for being able to control the formation of desired levels of these aldehydes.
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Affiliation(s)
- Bart A Smit
- Campina Innovation, Nieuwe Kanaal 7C, 6709PA Wageningen, The Netherlands
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30
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Saturation mutagenesis of putative catalytic residues of benzoylformate decarboxylase provides a challenge to the accepted mechanism. Proc Natl Acad Sci U S A 2008; 105:5733-8. [PMID: 18398009 DOI: 10.1073/pnas.0709657105] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Benzoylformate decarboxylase from Pseudomonas putida (PpBFDC) is a thiamin diphosphate-dependent enzyme that carries out the nonoxidative decarboxylation of aromatic 2-keto acids. The x-ray structure of PpBFDC suggested that Ser-26, His-70, and His-281 would play important roles in its catalytic mechanism, and the S26A, H70A, and H281A variants all exhibited greatly impaired catalytic activity. Based on stopped-flow studies with the alanine mutants, it was proposed that the histidine residues acted as acid-base catalysts, whereas Ser-26 was involved in substrate binding and played a significant, albeit less well defined, role in catalysis. While developing a saturation mutagenesis protocol to examine residues involved in PpBFDC substrate specificity, we tested the procedure on His-281. To our surprise, we found that His-281, which is thought to be necessary for protonation of the carbanion/enamine intermediate, could be replaced by phenyl alanine with only a 5-fold decrease in k(cat). Even more surprising were our subsequent observations (i) that His-70 could be replaced by threonine or leucine with approximately a 30-fold decrease in k(cat)/K(m) compared with a 4,000-fold decrease for the H70A variant and (ii) that Ser-26, which forms hydrogen bonds with the substrate carboxylate, could be replaced by threonine, leucine, or methionine without significant loss of activity. These results call into question the assigned roles for Ser-26, His-70, and His-281. Further, they demonstrate the danger in assigning catalytic function based solely on results with alanine mutants and show that saturation mutagenesis is a valuable tool in assessing the role and relative importance of putative catalytic residues.
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31
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Gocke D, Walter L, Gauchenova E, Kolter G, Knoll M, Berthold CL, Schneider G, Pleiss J, Müller M, Pohl M. Rational Protein Design of ThDP-Dependent Enzymes—Engineering Stereoselectivity. Chembiochem 2008; 9:406-12. [DOI: 10.1002/cbic.200700598] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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32
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Werther T, Spinka M, Tittmann K, Schütz A, Golbik R, Mrestani-Klaus C, Hübner G, König S. Amino acids allosterically regulate the thiamine diphosphate-dependent alpha-keto acid decarboxylase from Mycobacterium tuberculosis. J Biol Chem 2007; 283:5344-54. [PMID: 18086676 DOI: 10.1074/jbc.m706569200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The gene rv0853c from Mycobacterium tuberculosis strain H37Rv codes for a thiamine diphosphate-dependent alpha-keto acid decarboxylase (MtKDC), an enzyme involved in the amino acid degradation via the Ehrlich pathway. Steady state kinetic experiments were performed to determine the substrate specificity of MtKDC. The mycobacterial enzyme was found to convert a broad spectrum of branched-chain and aromatic alpha-keto acids. Stopped-flow kinetics showed that MtKDC is allosterically activated by alpha-keto acids. Even more, we demonstrate that also amino acids are potent activators of this thiamine diphosphate-dependent enzyme. Thus, metabolic flow through the Ehrlich pathway can be directly regulated at the decarboxylation step. The influence of amino acids on MtKDC catalysis was investigated, and implications for other thiamine diphosphate-dependent enzymes are discussed.
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Affiliation(s)
- Tobias Werther
- Institute of Biochemistry and Biotechnology, Faculty for Biological Sciences, Martin-Luther-University Halle-Wittenberg, 06120 Halle Saale, Germany
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33
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Gocke D, Nguyen CL, Pohl M, Stillger T, Walter L, Müller M. Branched-Chain Keto Acid Decarboxylase fromLactococcus lactis (KdcA), a Valuable Thiamine Diphosphate-Dependent Enzyme for Asymmetric CC Bond Formation. Adv Synth Catal 2007. [DOI: 10.1002/adsc.200700057] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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