1
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Johnston ML, Bonett EM, DeColli AA, Freel Meyers CL. Antibacterial Target DXP Synthase Catalyzes the Cleavage of d-Xylulose 5-Phosphate: a Study of Ketose Phosphate Binding and Ketol Transfer Reaction. Biochemistry 2022; 61:1810-1823. [PMID: 35998648 PMCID: PMC9531112 DOI: 10.1021/acs.biochem.2c00274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The bacterial enzyme 1-deoxy-d-xylulose 5-phosphate synthase (DXPS) catalyzes the formation of DXP from pyruvate and d-glyceraldehyde 3-phosphate (d-GAP) in a thiamin diphosphate (ThDP)-dependent manner. In addition to its role in isoprenoid biosynthesis, DXP is required for ThDP and pyridoxal phosphate biosynthesis. Due to its function as a branch-point enzyme and its demonstrated substrate and catalytic promiscuity, we hypothesize that DXPS could be key for bacterial adaptation in the dynamic metabolic landscape during infection. Prior work in the Freel Meyers laboratory has illustrated that DXPS displays relaxed specificity toward donor and acceptor substrates and varies acceptor specificity according to the donor used. We have reported that DXPS forms dihydroxyethyl (DHE)ThDP from ketoacid or aldehyde donor substrates via decarboxylation and deprotonation, respectively. Here, we tested other DHE donors and found that DXPS cleaves d-xylulose 5-phosphate (X5P) at C2-C3, producing DHEThDP through a third mechanism involving d-GAP elimination. We interrogated DXPS-catalyzed reactions using X5P as a donor substrate and illustrated (1) production of a semi-stable enzyme-bound intermediate and (2) O2, H+, and d-erythrose 4-phosphate act as acceptor substrates, highlighting a new transketolase-like activity of DXPS. Furthermore, we examined X5P binding to DXPS and suggest that the d-GAP binding pocket plays a crucial role in X5P binding and turnover. Overall, this study reveals a ketose-cleavage reaction catalyzed by DXPS, highlighting the remarkable flexibility for donor substrate usage by DXPS compared to other C-C bond-forming enzymes.
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Affiliation(s)
- Melanie L. Johnston
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Eucolona M. Bonett
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Caren L. Freel Meyers
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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2
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Berger A, Knak T, Kiffe-Delf AL, Mudrovcic K, Singh V, Njoroge M, Burckhardt BB, Gopalswamy M, Lungerich B, Ackermann L, Gohlke H, Chibale K, Kalscheuer R, Kurz T. Total Synthesis of the Antimycobacterial Natural Product Chlorflavonin and Analogs via a Late-Stage Ruthenium(II)-Catalyzed ortho-C(sp2)-H-Hydroxylation. Pharmaceuticals (Basel) 2022; 15:ph15080984. [PMID: 36015133 PMCID: PMC9415896 DOI: 10.3390/ph15080984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/01/2022] [Accepted: 08/08/2022] [Indexed: 12/04/2022] Open
Abstract
The continuous, worldwide spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) endanger the World Health Organization’s (WHO) goal to end the global TB pandemic by the year 2035. During the past 50 years, very few new drugs have been approved by medical agencies to treat drug-resistant TB. Therefore, the development of novel antimycobacterial drug candidates to combat the threat of drug-resistant TB is urgent. In this work, we developed and optimized a total synthesis of the antimycobacterial natural flavonoid chlorflavonin by selective ruthenium(II)-catalyzed ortho-C(sp2)-H-hydroxylation of a substituted 3′-methoxyflavonoid skeleton. We extended our methodology to synthesize a small compound library of 14 structural analogs. The new analogs were tested for their antimycobacterial in vitro activity against Mycobacterium tuberculosis (Mtb) and their cytotoxicity against various human cell lines. The most promising new analog bromflavonin exhibited improved antimycobacterial in vitro activity against the virulent H37Rv strain of Mtb (Minimal Inhibitory Concentrations (MIC90) = 0.78 μm). In addition, we determined the chemical and metabolic stability as well as the pKa values of chlorflavonin and bromflavonin. Furthermore, we established a quantitative structure–activity relationship model using a thermodynamic integration approach. Our computations may be used for suggesting further structural changes to develop improved derivatives.
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Affiliation(s)
- Alexander Berger
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
| | - Talea Knak
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
| | - Anna-Lene Kiffe-Delf
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Korana Mudrovcic
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
| | - Vinayak Singh
- South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Mathew Njoroge
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Bjoern B. Burckhardt
- Institute of Clinical Pharmacy and Pharmacotherapy, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Mohanraj Gopalswamy
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
| | - Beate Lungerich
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
| | - Lutz Ackermann
- Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstraße 2, 37077 Göttingen, Germany
| | - Holger Gohlke
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Kelly Chibale
- South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
- Drug Discovery and Development Centre (H3D), University of Cape Town, Rondebosch 7701, South Africa
| | - Rainer Kalscheuer
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Thomas Kurz
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany or
- Correspondence:
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3
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Seo H, Giannone RJ, Yang YH, Trinh CT. Proteome reallocation enables the selective de novo biosynthesis of non-linear, branched-chain acetate esters. Metab Eng 2022; 73:38-49. [PMID: 35561848 DOI: 10.1016/j.ymben.2022.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/21/2022] [Accepted: 05/06/2022] [Indexed: 10/25/2022]
Abstract
The one-carbon recursive ketoacid elongation pathway is responsible for making various branched-chain amino acids, aldehydes, alcohols, and acetate esters in living cells. Controlling selective microbial biosynthesis of these target molecules at high efficiency is challenging due to enzyme promiscuity, regulation, and metabolic burden. In this study, we present a systematic modular design approach to control proteome reallocation for selective microbial biosynthesis of branched-chain acetate esters. Through pathway modularization, we partitioned the branched-chain ester pathways into four submodules including keto-isovalerate submodule for converting pyruvate to keto-isovalerate, ketoacid elongation submodule for producing longer carbon-chain keto-acids, ketoacid decarboxylase submodule for converting ketoacids to alcohols, and alcohol acyltransferase submodule for producing branched-chain acetate esters by condensing alcohols and acetyl-CoA. By systematic manipulation of pathway gene replication and transcription, enzyme specificity of the first committed steps of these submodules, and downstream competing pathways, we demonstrated selective microbial production of isoamyl acetate over isobutyl acetate. We found that the optimized isoamyl acetate pathway globally redistributed the amino acid fractions in the proteomes and required up to 23-31% proteome reallocation at the expense of other cellular resources, such as those required to generate precursor metabolites and energy for growth and amino acid biosynthesis. From glucose fed-batch fermentation, the engineered strains produced isoamyl acetate up to a titer of 8.8 g/L (>0.25 g/L toxicity limit), a yield of 0.22 g/g (61% of maximal theoretical value), and 86% selectivity, achieving the highest titers, yields and selectivity of isoamyl acetate reported to date.
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Affiliation(s)
- Hyeongmin Seo
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN, USA; Center of Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Richard J Giannone
- Center of Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Yung-Hun Yang
- Department of Biological Engineering, Konkuk University, Seoul, South Korea
| | - Cong T Trinh
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN, USA; Center of Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
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4
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Yu S, Zheng B, Chen Z, Huo YX. Metabolic engineering of Corynebacterium glutamicum for producing branched chain amino acids. Microb Cell Fact 2021; 20:230. [PMID: 34952576 PMCID: PMC8709942 DOI: 10.1186/s12934-021-01721-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/11/2021] [Indexed: 11/10/2022] Open
Abstract
Background Branched chain amino acids (BCAAs) are widely applied in the food, pharmaceutical, and animal feed industries. Traditional chemical synthetic and enzymatic BCAAs production in vitro has been hampered by expensive raw materials, harsh reaction conditions, and environmental pollution. Microbial metabolic engineering has attracted considerable attention as an alternative method for BCAAs biosynthesis because it is environmentally friendly and delivers high yield. Main text Corynebacterium glutamicum (C. glutamicum) possesses clear genetic background and mature gene manipulation toolbox, and has been utilized as industrial host for producing BCAAs. Acetohydroxy acid synthase (AHAS) is a crucial enzyme in the BCAAs biosynthetic pathway of C. glutamicum, but feedback inhibition is a disadvantage. We therefore reviewed AHAS modifications that relieve feedback inhibition and then investigated the importance of AHAS modifications in regulating production ratios of three BCAAs. We have comprehensively summarized and discussed metabolic engineering strategies to promote BCAAs synthesis in C. glutamicum and offer solutions to the barriers associated with BCAAs biosynthesis. We also considered the future applications of strains that could produce abundant amounts of BCAAs. Conclusions Branched chain amino acids have been synthesized by engineering the metabolism of C. glutamicum. Future investigations should focus on the feedback inhibition and/or transcription attenuation mechanisms of crucial enzymes. Enzymes with substrate specificity should be developed and applied to the production of individual BCAAs. The strategies used to construct strains producing BCAAs provide guidance for the biosynthesis of other high value-added compounds.
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Affiliation(s)
- Shengzhu Yu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China
| | - Bo Zheng
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China
| | - Zhenya Chen
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China.
| | - Yi-Xin Huo
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China
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5
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L-valine production in Corynebacterium glutamicum based on systematic metabolic engineering: progress and prospects. Amino Acids 2021; 53:1301-1312. [PMID: 34401958 DOI: 10.1007/s00726-021-03066-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 08/11/2021] [Indexed: 10/20/2022]
Abstract
L-valine is an essential branched-chain amino acid that cannot be synthesized by the human body and has a wide range of applications in food, medicine and feed. Market demand has stimulated people's interest in the industrial production of L-valine. At present, the mutagenized or engineered Corynebacterium glutamicum is an effective microbial cell factory for producing L-valine. Because the biosynthetic pathway and metabolic network of L-valine are intricate and strictly regulated by a variety of key enzymes and genes, highly targeted metabolic engineering can no longer meet the demand for efficient biosynthesis of L-valine. In recent years, the development of omics technology has promoted the upgrading of traditional metabolic engineering to systematic metabolic engineering. This whole-cell-scale transformation strategy has become a productive method for developing L-valine producing strains. This review provides an overview of the biosynthesis and regulation mechanism of L-valine, and summarizes the current metabolic engineering techniques and strategies for constructing L-valine high-producing strains. Finally, the opinion of constructing a cell factory for efficiently biosynthesizing L-valine was proposed.
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6
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Yu H, Hernández López RI, Steadman D, Méndez‐Sánchez D, Higson S, Cázares‐Körner A, Sheppard TD, Ward JM, Hailes HC, Dalby PA. Engineering transketolase to accept both unnatural donor and acceptor substrates and produce α‐hydroxyketones. FEBS J 2019; 287:1758-1776. [DOI: 10.1111/febs.15108] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/26/2019] [Accepted: 10/23/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Haoran Yu
- Department of Biochemical Engineering University College London UK
| | | | | | | | - Sally Higson
- Department of Chemistry University College London UK
| | | | | | - John M. Ward
- Department of Biochemical Engineering University College London UK
| | | | - Paul A. Dalby
- Department of Biochemical Engineering University College London UK
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7
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Liu Y, Wang X, Zhan J, Hu J. The 138th residue of acetohydroxyacid synthase in Corynebacterium glutamicum is important for the substrate binding specificity. Enzyme Microb Technol 2019; 129:109357. [DOI: 10.1016/j.enzmictec.2019.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 05/12/2019] [Accepted: 06/01/2019] [Indexed: 11/28/2022]
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8
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Lonhienne T, Garcia MD, Noble C, Harmer J, Fraser JA, Williams CM, Guddat LW. High Resolution Crystal Structures of the Acetohydroxyacid Synthase‐Pyruvate Complex Provide New Insights into Its Catalytic Mechanism. ChemistrySelect 2017. [DOI: 10.1002/slct.201702128] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Thierry Lonhienne
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane 4072 QLD Australia
| | - Mario D. Garcia
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane 4072 QLD Australia
| | - Chris Noble
- Centre for Advanced Imaging The University of Queensland Brisbane 4072 QLD Australia
| | - Jeffrey Harmer
- Centre for Advanced Imaging The University of Queensland Brisbane 4072 QLD Australia
| | - James A. Fraser
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane 4072 QLD Australia
| | - Craig M. Williams
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane 4072 QLD Australia
| | - Luke W. Guddat
- School of Chemistry and Molecular Biosciences The University of Queensland Brisbane 4072 QLD Australia
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9
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Liu Y, Li Y, Wang X. Molecular evolution of acetohydroxyacid synthase in bacteria. Microbiologyopen 2017; 6. [PMID: 28782269 PMCID: PMC5727371 DOI: 10.1002/mbo3.524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 06/21/2017] [Accepted: 06/29/2017] [Indexed: 11/16/2022] Open
Abstract
Acetohydroxyacid synthase (AHAS) is the key enzyme in the biosynthetic pathways of branched chain amino acids in bacteria. Since it does not exist in animal and plant cells, AHAS is an attractive target for developing antimicrobials and herbicides. In some bacteria, there is a single copy of AHAS, while in others there are multiple copies. Therefore, it is necessary to investigate the origin and evolutionary pathway of various AHASs in bacteria. In this study, all the available protein sequences of AHAS in bacteria were investigated, and an evolutionary model of AHAS in bacteria is proposed, according to gene structure, organization and phylogeny. Multiple copies of AHAS in some bacteria might be evolved from the single copy of AHAS, the ancestor. Gene duplication, domain deletion and horizontal gene transfer might occur during the evolution of this enzyme. The results show the biological significance of AHAS, help to understand the functions of various AHASs in bacteria, and would be useful for developing industrial production strains of branched chain amino acids or novel antimicrobials.
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Affiliation(s)
- Yadi Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China
| | - Yanyan Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Xiaoyuan Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,School of Biotechnology, Jiangnan University, Wuxi, China.,Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi, China
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10
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Mechanistic and Structural Insight to an Evolved Benzoylformate Decarboxylase with Enhanced Pyruvate Decarboxylase Activity. Catalysts 2016. [DOI: 10.3390/catal6120190] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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11
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Liu Y, Li Y, Wang X. Acetohydroxyacid synthases: evolution, structure, and function. Appl Microbiol Biotechnol 2016; 100:8633-49. [DOI: 10.1007/s00253-016-7809-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 07/28/2016] [Accepted: 08/12/2016] [Indexed: 10/21/2022]
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12
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Copley SD. An evolutionary biochemist's perspective on promiscuity. Trends Biochem Sci 2015; 40:72-8. [PMID: 25573004 DOI: 10.1016/j.tibs.2014.12.004] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 12/08/2014] [Accepted: 12/08/2014] [Indexed: 12/31/2022]
Abstract
Evolutionary biochemists define enzyme promiscuity as the ability to catalyze secondary reactions that are physiologically irrelevant, either because they are too inefficient to affect fitness or because the enzyme never encounters the substrate. Promiscuous activities are common because evolution of a perfectly specific active site is both difficult and unnecessary; natural selection ceases when the performance of a protein is 'good enough' that it no longer affects fitness. Although promiscuous functions are accidental and physiologically irrelevant, they are of great importance because they provide opportunities for the evolution of new functions in nature and in the laboratory, as well as targets for therapeutic drugs and tools for a wide range of technological applications.
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Affiliation(s)
- Shelley D Copley
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO 80309, USA; Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO 80309, USA.
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13
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Lee SC, Jung IP, Baig IA, Chien PN, La IJ, Yoon MY. Mutational analysis of critical residues of FAD-independent catabolic acetolactate synthase from Enterococcus faecalis V583. Int J Biol Macromol 2014; 72:104-9. [PMID: 25128823 DOI: 10.1016/j.ijbiomac.2014.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 08/02/2014] [Accepted: 08/04/2014] [Indexed: 10/24/2022]
Abstract
Catabolic acetolactate synthase (cALS) from Enterococcus faecalis is a FAD-independent enzyme, which catalyzes the condensation of two molecules of pyruvate to produce acetolactate. Mutational and kinetic analyses of variants suggested the importance of H111, Q112, and Q411 residues for catalysis in cALS. The wild-type and variants were expressed as equally soluble proteins and co-migrated to a size of 60 kDa on SDS-PAGE. Importantly, H111 in cALS, which is widely present as phenylalanine in many other ThDP-dependent enzymes, plays a crucial role in substrate binding. Interestingly, the H111 variants, H111R and H111F, demonstrated altered specific activity of H111 variants with 17- and 26-fold increases in Km, respectively, compared to wild-type cALS. Furthermore, Q112 variants, Q112E, Q112N, and Q112V, exhibited significantly lower specific activity with 70-, 15-, and 10-fold higher Ks for ThDP, respectively. In the case of Q411, the variant Q411E showed a 10-fold rise in Km and a 20-fold increase in Ks for ThDP. Further, the molecular docking results indicated that the binding mode of ThDP was slightly affected in the variants of cALS. Based on these results, we suggest that H111 plays a role in substrate binding, and further suggest that Q112 and Q411 might be involved in ThDP binding of cALS.
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Affiliation(s)
- Sang-Choon Lee
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea
| | - In-Pil Jung
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea
| | - Irshad Ahmed Baig
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea
| | - Pham Ngoc Chien
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea
| | - Im-Joung La
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea
| | - Moon-Young Yoon
- Department of Chemistry, College of Natural Science, Hanyang University, Seoul 133-791, Republic of Korea.
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14
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Characterization and modification of enzymes in the 2-ketoisovalerate biosynthesis pathway of Ralstonia eutropha H16. Appl Microbiol Biotechnol 2014; 99:761-74. [DOI: 10.1007/s00253-014-5965-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 11/27/2022]
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15
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Xu Y, Chu H, Gao C, Tao F, Zhou Z, Li K, Li L, Ma C, Xu P. Systematic metabolic engineering of Escherichia coli for high-yield production of fuel bio-chemical 2,3-butanediol. Metab Eng 2014; 23:22-33. [DOI: 10.1016/j.ymben.2014.02.004] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 01/15/2014] [Accepted: 02/03/2014] [Indexed: 12/25/2022]
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16
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Zhao Y, Niu C, Wen X, Xi Z. The minimum activation peptide from ilvH can activate the catalytic subunit of AHAS from different species. Chembiochem 2013; 14:746-52. [PMID: 23512804 DOI: 10.1002/cbic.201200680] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Indexed: 11/10/2022]
Abstract
Acetohydroxyacid synthases (AHASs), which catalyze the first step in the biosynthesis of branched-chain amino acids, are composed of a catalytic subunit (CSU) and a regulatory subunit (RSU). The CSU harbors the catalytic site, and the RSU is responsible for the activation and feedback regulation of the CSU. Previous results from Chipman and co-workers and our lab have shown that heterologous activation can be achieved among isozymes of Escherichia coli AHAS. It would be interesting to find the minimum peptide of ilvH (the RSU of E. coli AHAS III) that could activate other E. coli CSUs, or even those of ## species. In this paper, C-terminal, N-terminal, and C- and N-terminal truncation mutants of ilvH were constructed. The minimum peptide to activate ilvI (the CSU of E. coli AHAS III) was found to be ΔN 14-ΔC 89. Moreover, this peptide could not only activate its homologous ilvI and heterologous ilvB (CSU of E. coli AHAS I), but also heterologously activate the CSUs of AHAS from Saccharomyces cerevisiae, Arabidopsis thaliana, and Nicotiana plumbaginifolia. However, this peptide totally lost its ability for feedback regulation by valine, thus suggesting different elements for enzymatic activation and feedback regulation. Additionally, the apparent dissociation constant (Kd ) of ΔN 14-ΔC 89 when binding CSUs of different species was found to be 9.3-66.5 μM by using microscale thermophoresis. The ability of this peptide to activate different CSUs does not correlate well with its binding ability (Kd ) to these CSUs, thus implying that key interactions by specific residues is more important than binding ability in promoting enzymatic reactions. The high sequence similarity of the peptide ΔN 14-ΔC 89 to RSUs across species hints that this peptide represents the minimum activation motif in RSU and that it regulates all AHASs.
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Affiliation(s)
- Yuefang Zhao
- Department of Chemical Biology and State Key Laboratory of Elemento-organic Chemistry, Nankai University, Weijin 94, Tianjin 300071, China
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17
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Schröder-Tittmann K, Meyer D, Arens J, Wechsler C, Tietzel M, Golbik R, Tittmann K. Alternating Sites Reactivity Is a Common Feature of Thiamin Diphosphate-Dependent Enzymes As Evidenced by Isothermal Titration Calorimetry Studies of Substrate Binding. Biochemistry 2013; 52:2505-7. [DOI: 10.1021/bi301591e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kathrin Schröder-Tittmann
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
| | - Danilo Meyer
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
| | - Johannes Arens
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
| | - Cindy Wechsler
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
| | - Michael Tietzel
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
| | - Ralph Golbik
- Martin-Luther University Halle-Wittenberg, 06120 Halle/Salle, Germany
| | - Kai Tittmann
- Göttingen Center for
Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, 37077 Göttingen,
Germany
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18
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Müller M, Sprenger GA, Pohl M. CC bond formation using ThDP-dependent lyases. Curr Opin Chem Biol 2013; 17:261-70. [PMID: 23523314 DOI: 10.1016/j.cbpa.2013.02.017] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 02/02/2013] [Accepted: 02/14/2013] [Indexed: 01/17/2023]
Abstract
The present review summarizes recent achievements in enzymatic thiamine catalysis during the past three years. With well-established enzymes such as BAL, PDC and TK new reactions have been identified and respective variants were prepared, which enable access to stereoisomeric products. Further we highlight recent progress with 'new' ThDP-dependent enzymes like MenD and PigD, which catalyze the Stetter-like 1,4 addition of aldehydes and YerE, which is the first known ThDP-dependent enzyme accepting ketones as acceptors.
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Affiliation(s)
- Michael Müller
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, 79104 Freiburg, Germany.
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19
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Zhao Y, Wen X, Niu C, Xi Z. Arginine 26 and Aspartic Acid 69 of the Regulatory Subunit are Key Residues of Subunits Interaction of Acetohydroxyacid Synthase Isozyme III fromE. coli. Chembiochem 2012; 13:2445-54. [DOI: 10.1002/cbic.201200362] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Indexed: 11/08/2022]
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20
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Nemeria N, Binshtein E, Patel H, Balakrishnan A, Vered I, Shaanan B, Barak Z, Chipman D, Jordan F. Glyoxylate carboligase: a unique thiamin diphosphate-dependent enzyme that can cycle between the 4'-aminopyrimidinium and 1',4'-iminopyrimidine tautomeric forms in the absence of the conserved glutamate. Biochemistry 2012; 51:7940-52. [PMID: 22970650 DOI: 10.1021/bi300893v] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glyoxylate carboligase (GCL) is a thiamin diphosphate (ThDP)-dependent enzyme, which catalyzes the decarboxylation of glyoxylate and ligation to a second molecule of glyoxylate to form tartronate semialdehyde (TSA). This enzyme is unique among ThDP enzymes in that it lacks a conserved glutamate near the N1' atom of ThDP (replaced by Val51) or any other potential acid-base side chains near ThDP. The V51D substitution shifts the pH optimum to 6.0-6.2 (pK(a) of 6.2) for TSA formation from pH 7.0-7.7 in wild-type GCL. This pK(a) is similar to the pK(a) of 6.1 for the 1',4'-iminopyrimidine (IP)-4'-aminopyrimidinium (APH(+)) protonic equilibrium, suggesting that the same groups control both ThDP protonation and TSA formation. The key covalent ThDP-bound intermediates were identified on V51D GCL by a combination of steady-state and stopped-flow circular dichroism methods, yielding rate constants for their formation and decomposition. It was demonstrated that active center variants with substitution at I393 could synthesize (S)-acetolactate from pyruvate solely, and acetylglycolate derived from pyruvate as the acetyl donor and glyoxylate as the acceptor, implying that this substitutent favored pyruvate as the donor in carboligase reactions. Consistent with these observations, the I393A GLC variants could stabilize the predecarboxylation intermediate analogues derived from acetylphosphinate, propionylphosphinate, and methyl acetylphosphonate in their IP tautomeric forms notwithstanding the absence of the conserved glutamate. The role of the residue at the position occupied typically by the conserved Glu controls the pH dependence of kinetic parameters, while the entire reaction sequence could be catalyzed by ThDP itself, once the APH(+) form is accessible.
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Affiliation(s)
- Natalia Nemeria
- Department of Life Sciences, Ben-Gurion University , P.O. Box 653, Beer-Sheva 84105, Israel
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21
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Belenky I, Steinmetz A, Vyazmensky M, Barak Z, Tittmann K, Chipman DM. Many of the functional differences between acetohydroxyacid synthase (AHAS) isozyme I and other AHASs are a result of the rapid formation and breakdown of the covalent acetolactate-thiamin diphosphate adduct in AHAS I. FEBS J 2012; 279:1967-79. [DOI: 10.1111/j.1742-4658.2012.08577.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Grundman O, Khozin-Goldberg I, Raveh D, Cohen Z, Vyazmensky M, Boussiba S, Shapira M. Cloning, mutagenesis, and characterization of the microalga Parietochloris incisa acetohydroxyacid synthase, and its possible use as an endogenous selection marker. Biotechnol Bioeng 2012; 109:2340-8. [PMID: 22488216 DOI: 10.1002/bit.24515] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Revised: 03/04/2012] [Accepted: 03/23/2012] [Indexed: 11/10/2022]
Abstract
Parietochloris incisa is an oleaginous fresh water green microalga that accumulates an unusually high content of the valuable long-chain polyunsaturated fatty acid (LC-PUFA) arachidonic acid within triacylglycerols in cytoplasmic lipid bodies. Here, we describe cloning and mutagenesis of the P. incisa acetohydroxyacid synthase (PiAHAS) gene for use as an herbicide resistance selection marker for transformation. Use of an endogenous gene circumvents the risks and regulatory difficulties of cultivating antibiotic-resistant organisms. AHAS is present in plants and microorganisms where it catalyzes the first essential step in the synthesis of branched-chain amino acids. It is the target enzyme of the herbicide sulfometuron methyl (SMM), which effectively inhibits growth of bacteria and plants. Several point mutations of AHAS are known to confer herbicide resistance. We cloned the cDNA that encodes PiAHAS and introduced a W605S point mutation (PimAHAS). Catalytic activity and herbicide resistance of the wild-type and mutant proteins were characterized in the AHAS-deficient E. coli, BUM1 strain. Cloned PiAHAS wild-type and mutant genes complemented AHAS-deficient bacterial growth. Furthermore, bacteria expressing the mutant PiAHAS exhibited high resistance to SMM. Purified PiAHAS wild-type and mutant proteins were assayed for enzymatic activity and herbicide resistance. The W605S mutation was shown to cause a twofold decrease in enzymatic activity and in affinity for the Pyruvate substrate. However, the mutant exhibited 7 orders of magnitude higher resistance to the SMM herbicide than that of the wild type.
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Affiliation(s)
- Omer Grundman
- Microalgal Biotechnology Laboratory, French Associates Institute of Agriculture and Biotechnology of Drylands, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
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23
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Gedi V, Yoon MY. Bacterial acetohydroxyacid synthase and its inhibitors - a summary of their structure, biological activity and current status. FEBS J 2012; 279:946-63. [DOI: 10.1111/j.1742-4658.2012.08505.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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24
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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: 25] [Impact Index Per Article: 1.9] [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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25
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Brammer LA, Smith JM, Wade H, Meyers CF. 1-Deoxy-D-xylulose 5-phosphate synthase catalyzes a novel random sequential mechanism. J Biol Chem 2011; 286:36522-31. [PMID: 21878632 DOI: 10.1074/jbc.m111.259747] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Emerging resistance of human pathogens to anti-infective agents make it necessary to develop new agents to treat infection. The methylerythritol phosphate pathway has been identified as an anti-infective target, as this essential isoprenoid biosynthetic pathway is widespread in human pathogens but absent in humans. The first enzyme of the pathway, 1-deoxy-D-xylulose 5-phosphate (DXP) synthase, catalyzes the formation of DXP via condensation of D-glyceraldehyde 3-phosphate (D-GAP) and pyruvate in a thiamine diphosphate-dependent manner. Structural analysis has revealed a unique domain arrangement suggesting opportunities for the selective targeting of DXP synthase; however, reports on the kinetic mechanism are conflicting. Here, we present the results of tryptophan fluorescence binding and kinetic analyses of DXP synthase and propose a new model for substrate binding and mechanism. Our results are consistent with a random sequential kinetic mechanism, which is unprecedented in this enzyme class.
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Affiliation(s)
- Leighanne A Brammer
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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26
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Shim DJ, Nemeria NS, Balakrishnan A, Patel H, Song J, Wang J, Jordan F, Farinas ET. Assignment of function to histidines 260 and 298 by engineering the E1 component of the Escherichia coli 2-oxoglutarate dehydrogenase complex; substitutions that lead to acceptance of substrates lacking the 5-carboxyl group. Biochemistry 2011; 50:7705-9. [PMID: 21809826 DOI: 10.1021/bi200936n] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first component (E1o) of the Escherichia coli 2-oxoglutarate dehydrogenase complex (OGDHc) was engineered to accept substrates lacking the 5-carboxylate group by subjecting H260 and H298 to saturation mutagenesis. Apparently, H260 is required for substrate recognition, but H298 could be replaced with hydrophobic residues of similar molecular volume. To interrogate whether the second component would allow synthesis of acyl-coenzyme A derivatives, hybrid complexes consisting of recombinant components of OGDHc (o) and pyruvate dehydrogenase (p) enzymes were constructed, suggesting that a different component is the "gatekeeper" for specificity for these two multienzyme complexes in bacteria, E1p for pyruvate but E2o for 2-oxoglutarate.
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Affiliation(s)
- Da Jeong Shim
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
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27
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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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28
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Vyazmensky M, Steinmetz A, Meyer D, Golbik R, Barak Z, Tittmann K, Chipman DM. Significant Catalytic Roles for Glu47 and Gln 110 in All Four of the C−C Bond-Making and -Breaking Steps of the Reactions of Acetohydroxyacid Synthase II. Biochemistry 2011; 50:3250-60. [DOI: 10.1021/bi102051h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Maria Vyazmensky
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
| | - Andrea Steinmetz
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Danilo Meyer
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Ralph Golbik
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Ze'ev Barak
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
| | - Kai Tittmann
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - David M. Chipman
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
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29
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Meyer D, Walter L, Kolter G, Pohl M, Müller M, Tittmann K. Conversion of Pyruvate Decarboxylase into an Enantioselective Carboligase with Biosynthetic Potential. J Am Chem Soc 2011; 133:3609-16. [PMID: 21341803 DOI: 10.1021/ja110236w] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Danilo Meyer
- Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
- Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Strasse 3, D-06120 Halle/Saale, Germany
| | - Lydia Walter
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Geraldine Kolter
- Institute of Biotechnology 2, Research Centre Jülich, 52425 Jülich, Germany
| | - Martina Pohl
- Institute of Biotechnology 2, Research Centre Jülich, 52425 Jülich, Germany
| | - Michael Müller
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-University Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Kai Tittmann
- Albrecht-von-Haller-Institute for Plant Sciences and Göttingen Center for Molecular Biosciences, Georg-August-University Göttingen, Ernst-Caspari-Haus, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
- Institute of Biochemistry and Biotechnology, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Strasse 3, D-06120 Halle/Saale, Germany
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30
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Gedi V, Koo BS, Kim DE, Yoon MY. Characterization of Acetohydroxyacid Synthase Cofactors from Haemophilus influenza. B KOREAN CHEM SOC 2010. [DOI: 10.5012/bkcs.2010.31.12.3782] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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