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Ahmad N, Sharma P, Sharma S, Singh TP. Structure of a novel form of phosphopantetheine adenylyltransferase from Klebsiella pneumoniae at 2.59 Å resolution. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2024; 53:147-157. [PMID: 38456905 DOI: 10.1007/s00249-024-01703-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/16/2024] [Accepted: 02/10/2024] [Indexed: 03/09/2024]
Abstract
Phosphopantetheine adenylyltransferase (EC. 2.7.7.3, PPAT) catalyzes the penultimate step of the multistep reaction in the coenzyme A (CoA) biosynthesis pathway. In this step, an adenylyl group from adenosine triphosphate (ATP) is transferred to 4'-phosphopantetheine (PNS) yielding 3'-dephospho-coenzyme A (dpCoA) and pyrophosphate (PPi). PPAT from strain C3 of Klebsiella pneumoniae (KpPPAT) was cloned, expressed and purified. It was crystallized using 0.1 M HEPES buffer and PEG10000 at pH 7.5. The crystals belonged to tetragonal space group P41212 with cell dimensions of a = b = 72.82 Å and c = 200.37 Å. The structure was determined using the molecular replacement method and refined to values of 0.208 and 0.255 for Rcryst and Rfree factors, respectively. The structure determination showed the presence of three crystallographically independent molecules A, B and C in the asymmetric unit. The molecules A and B are observed in the form of a dimer in the asymmetric unit while molecule C belongs to the second dimer whose partner is related by crystallographic twofold symmetry. The polypeptide chain of KpPPAT folds into a β/α structure. The conformations of the side chains of several residues in the substrate binding site in KpPPAT are significantly different from those reported in other PPATs. As a result, the modes of binding of substrates, phosphopantetheine (PNS) and adenosine triphosphate (ATP) differ considerably. The binding studies using fluorescence spectroscopy indicated a KD value of 3.45 × 10-4 M for ATP which is significantly lower than the corresponding values reported for PPAT from other species.
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Affiliation(s)
- Nabeel Ahmad
- Department of Biophysics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Pradeep Sharma
- Department of Biophysics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Sujata Sharma
- Department of Biophysics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.
| | - Tej P Singh
- Department of Biophysics, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.
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2
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Zhao K, Tang H, Zhang B, Zou S, Liu Z, Zheng Y. Microbial production of vitamin B5: current status and prospects. Crit Rev Biotechnol 2023; 43:1172-1192. [PMID: 36210178 DOI: 10.1080/07388551.2022.2104690] [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: 11/21/2021] [Accepted: 07/01/2022] [Indexed: 11/03/2022]
Abstract
Vitamin B5, also called D-pantothenic acid (D-PA), is a necessary micronutrient that plays an essential role in maintaining the physiological function of an organism. It is widely used in: food, medicine, feed, cosmetics, and other fields. Currently, the production of D-PA in industry heavily relies on chemical processes and enzymatic catalysis. With an increasing demand on the market, replacing chemical-based production of D-PA with microbial fermentation utilizing renewable resources is necessary. In this review, the physiological role and applications of D-PA were firstly introduced, after which the biosynthesis pathways and enzymes will be summarized. Subsequently, a series of cell factory development strategies for excessive D-PA production are analyzed and discussed. Finally, the prospect of microbial production of D-PA production has been prospected.
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Affiliation(s)
- Kuo Zhao
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
| | - Heng Tang
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
| | - Bo Zhang
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
| | - Shuping Zou
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
| | - Zhiqiang Liu
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
| | - Yuguo Zheng
- National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, PR China
- College of Biotechnology and Bioengineering, Key Laboratory of Bioorganic Synthesis of Zhejiang Province, Zhejiang University of Technology, Hangzhou, PR China
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Harrison SA, Webb WL, Rammu H, Lane N. Prebiotic Synthesis of Aspartate Using Life's Metabolism as a Guide. Life (Basel) 2023; 13:life13051177. [PMID: 37240822 DOI: 10.3390/life13051177] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 04/29/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
A protometabolic approach to the origins of life assumes that the conserved biochemistry of metabolism has direct continuity with prebiotic chemistry. One of the most important amino acids in modern biology is aspartic acid, serving as a nodal metabolite for the synthesis of many other essential biomolecules. Aspartate's prebiotic synthesis is complicated by the instability of its precursor, oxaloacetate. In this paper, we show that the use of the biologically relevant cofactor pyridoxamine, supported by metal ion catalysis, is sufficiently fast to offset oxaloacetate's degradation. Cu2+-catalysed transamination of oxaloacetate by pyridoxamine achieves around a 5% yield within 1 h, and can operate across a broad range of pH, temperature, and pressure. In addition, the synthesis of the downstream product β-alanine may also take place in the same reaction system at very low yields, directly mimicking an archaeal synthesis route. Amino group transfer supported by pyridoxal is shown to take place from aspartate to alanine, but the reverse reaction (alanine to aspartate) shows a poor yield. Overall, our results show that the nodal metabolite aspartate and related amino acids can indeed be synthesised via protometabolic pathways that foreshadow modern metabolism in the presence of the simple cofactor pyridoxamine and metal ions.
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Affiliation(s)
- Stuart A Harrison
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - William L Webb
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Hanadi Rammu
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
| | - Nick Lane
- Centre for Life's Origins and Evolution (CLOE), Department of Genetics, Evolution and Environment, University College London, London WC1E 6BT, UK
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Yan W, Zheng Y, Dou C, Zhang G, Arnaout T, Cheng W. The pathogenic mechanism of Mycobacterium tuberculosis: implication for new drug development. MOLECULAR BIOMEDICINE 2022; 3:48. [PMID: 36547804 PMCID: PMC9780415 DOI: 10.1186/s43556-022-00106-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 11/15/2022] [Indexed: 12/24/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is a tenacious pathogen that has latently infected one third of the world's population. However, conventional TB treatment regimens are no longer sufficient to tackle the growing threat of drug resistance, stimulating the development of innovative anti-tuberculosis agents, with special emphasis on new protein targets. The Mtb genome encodes ~4000 predicted proteins, among which many enzymes participate in various cellular metabolisms. For example, more than 200 proteins are involved in fatty acid biosynthesis, which assists in the construction of the cell envelope, and is closely related to the pathogenesis and resistance of mycobacteria. Here we review several essential enzymes responsible for fatty acid and nucleotide biosynthesis, cellular metabolism of lipids or amino acids, energy utilization, and metal uptake. These include InhA, MmpL3, MmaA4, PcaA, CmaA1, CmaA2, isocitrate lyases (ICLs), pantothenate synthase (PS), Lysine-ε amino transferase (LAT), LeuD, IdeR, KatG, Rv1098c, and PyrG. In addition, we summarize the role of the transcriptional regulator PhoP which may regulate the expression of more than 110 genes, and the essential biosynthesis enzyme glutamine synthetase (GlnA1). All these enzymes are either validated drug targets or promising target candidates, with drugs targeting ICLs and LAT expected to solve the problem of persistent TB infection. To better understand how anti-tuberculosis drugs act on these proteins, their structures and the structure-based drug/inhibitor designs are discussed. Overall, this investigation should provide guidance and support for current and future pharmaceutical development efforts against mycobacterial pathogenesis.
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Affiliation(s)
- Weizhu Yan
- grid.412901.f0000 0004 1770 1022Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041 China
| | - Yanhui Zheng
- grid.412901.f0000 0004 1770 1022Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041 China
| | - Chao Dou
- grid.412901.f0000 0004 1770 1022Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041 China
| | - Guixiang Zhang
- grid.13291.380000 0001 0807 1581Division of Gastrointestinal Surgery, Department of General Surgery and Gastric Cancer center, West China Hospital, Sichuan University, No. 37. Guo Xue Xiang, Chengdu, 610041 China
| | - Toufic Arnaout
- Kappa Crystals Ltd., Dublin, Ireland ,MSD Dunboyne BioNX, Co. Meath, Ireland
| | - Wei Cheng
- grid.412901.f0000 0004 1770 1022Division of Respiratory and Critical Care Medicine, Respiratory Infection and Intervention Laboratory of Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu, 610041 China
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Naorem RS, Pangabam BD, Bora SS, Goswami G, Barooah M, Hazarika DJ, Fekete C. Identification of Putative Vaccine and Drug Targets against the Methicillin-Resistant Staphylococcus aureus by Reverse Vaccinology and Subtractive Genomics Approaches. Molecules 2022; 27:2083. [PMID: 35408485 PMCID: PMC9000511 DOI: 10.3390/molecules27072083] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/18/2022] [Accepted: 03/21/2022] [Indexed: 01/23/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen and responsible for causing life-threatening infections. The emergence of hypervirulent and multidrug-resistant (MDR) S. aureus strains led to challenging issues in antibiotic therapy. Consequently, the morbidity and mortality rates caused by S. aureus infections have a substantial impact on health concerns. The current worldwide prevalence of MRSA infections highlights the need for long-lasting preventive measures and strategies. Unfortunately, effective measures are limited. In this study, we focus on the identification of vaccine candidates and drug target proteins against the 16 strains of MRSA using reverse vaccinology and subtractive genomics approaches. Using the reverse vaccinology approach, 4 putative antigenic proteins were identified; among these, PrsA and EssA proteins were found to be more promising vaccine candidates. We applied a molecular docking approach of selected 8 drug target proteins with the drug-like molecules, revealing that the ZINC4235426 as potential drug molecule with favorable interactions with the target active site residues of 5 drug target proteins viz., biotin protein ligase, HPr kinase/phosphorylase, thymidylate kinase, UDP-N-acetylmuramoyl-L-alanyl-D-glutamate-L-lysine ligase, and pantothenate synthetase. Thus, the identified proteins can be used for further rational drug or vaccine design to identify novel therapeutic agents for the treatment of multidrug-resistant staphylococcal infection.
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Affiliation(s)
- Romen Singh Naorem
- Department of General and Environmental Microbiology, Institute of Biology and Sport Biology, University of Pécs, Ifusag utja. 6, 7624 Pecs, Hungary; (R.S.N.); (B.D.P.)
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat 785013, India; (M.B.); (D.J.H.)
| | - Bandana Devi Pangabam
- Department of General and Environmental Microbiology, Institute of Biology and Sport Biology, University of Pécs, Ifusag utja. 6, 7624 Pecs, Hungary; (R.S.N.); (B.D.P.)
| | - Sudipta Sankar Bora
- DBT—North East Centre for Agricultural Biotechnology (DBT-AAU Center), Assam Agricultural University, Jorhat 785013, India;
| | - Gunajit Goswami
- Multidisciplinary Research Unit, Jorhat Medical College and Hospital, Jorhat 785008, India;
| | - Madhumita Barooah
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat 785013, India; (M.B.); (D.J.H.)
- DBT—North East Centre for Agricultural Biotechnology (DBT-AAU Center), Assam Agricultural University, Jorhat 785013, India;
| | - Dibya Jyoti Hazarika
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat 785013, India; (M.B.); (D.J.H.)
| | - Csaba Fekete
- Department of General and Environmental Microbiology, Institute of Biology and Sport Biology, University of Pécs, Ifusag utja. 6, 7624 Pecs, Hungary; (R.S.N.); (B.D.P.)
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Tadi SRR, Nehru G, Limaye AM, Sivaprakasam S. High-level expression and optimization of pantoate-β-alanine ligase in Bacillus megaterium for the enhanced biocatalytic production of D-pantothenic acid. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2022; 59:917-926. [PMID: 35153321 PMCID: PMC8814086 DOI: 10.1007/s13197-021-05093-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 02/28/2021] [Accepted: 04/04/2021] [Indexed: 11/30/2022]
Abstract
D-Pantothenic acid (DPA), also known as vitamin B5 is associated with several biological functions and its deficiency causes metabolic and energetic disorders in humans. Fortification of foods with DPA is the viable option to address this risk. DPA biological production route employs pantoate-β-alanine ligase (PBL) as the key enzyme, which avoids the tedious and time-consuming optical resolution process. The selection of an efficient PBL enzyme is vital for the biological production of DPA. In this study, the panC gene encoding PBL from Escherichia coli, Bacillus megaterium, Corynebacterium glutamicum and Bacillus subtilis was expressed in B. megaterium. B. subtilis derived panC exhibited high PBL activity 61.62 ± 2.15 U/mL. Co-expression of phosphoenolpyruvate carboxykinase (pckA) did not improve the DPA production in B. megaterium. Biocatalytic fed-batch fermentation with externally supplemented precursor substrates (D-pantoic acid and β-alanine) improved DPA titer to 45.56 ± 0.53 g/L. Daily dietary requirements of DPA for different age groups (including babies, small children, athletes and elderly people) is steadily increasing and the improved DPA production addressed in this study offers advantage for its application in fortification of food products meeting the emerging nutritional demand. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13197-021-05093-6.
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Affiliation(s)
- Subbi Rami Reddy Tadi
- BioPAT Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039 India
| | - Ganesh Nehru
- BioPAT Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039 India
| | - Anil Mukund Limaye
- The Molecular Endocrinology Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039 India
| | - Senthilkumar Sivaprakasam
- BioPAT Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039 India
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7
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Thomès L, Lescure A. Mosaic Evolution of the Phosphopantothenate Biosynthesis Pathway in Bacteria and Archaea. Genome Biol Evol 2020; 13:6035135. [PMID: 33320181 PMCID: PMC7883664 DOI: 10.1093/gbe/evaa262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2020] [Indexed: 11/13/2022] Open
Abstract
Phosphopantothenate is a precursor to synthesis of coenzyme A, a molecule essential to many metabolic pathways. Organisms of the archaeal phyla were shown to utilize a different phosphopantothenate biosynthetic pathway from the eukaryotic and bacterial one. In this study, we report that symbiotic bacteria from the group Candidatus poribacteria present enzymes of the archaeal pathway, namely pantoate kinase and phosphopantothenate synthetase, mirroring what was demonstrated for Picrophilus torridus, an archaea partially utilizing the bacterial pathway. Our results not only support the ancient origin of the coenzyme A pathway in the three domains of life but also highlight its complex and dynamic evolution. Importantly, this study helps to improve protein annotation for this pathway in the C. poribacteria group and other related organisms.
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Affiliation(s)
- Luc Thomès
- Architecture et Réactivité de l'ARN, CNRS, UPR9002, Université de Strasbourg, France
| | - Alain Lescure
- Architecture et Réactivité de l'ARN, CNRS, UPR9002, Université de Strasbourg, France
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8
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Cornell RB. Membrane Lipids Assist Catalysis by CTP: Phosphocholine Cytidylyltransferase. J Mol Biol 2020; 432:5023-5042. [PMID: 32234309 DOI: 10.1016/j.jmb.2020.03.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/22/2020] [Accepted: 03/25/2020] [Indexed: 02/06/2023]
Abstract
While most of the articles in this issue review the workings of integral membrane enzymes, in this review, we describe the catalytic mechanism of an enzyme that contains a soluble catalytic domain but appears to catalyze its reaction on the membrane surface, anchored and assisted by a separate regulatory amphipathic helical domain and inter-domain linker. Membrane partitioning of CTP: phosphocholine cytidylyltransferase (CCT), a key regulatory enzyme of phosphatidylcholine metabolism, is regulated chiefly by changes in membrane phospholipid composition, and boosts the enzyme's catalytic efficiency >200-fold. Catalytic enhancement by membrane binding involves the displacement of an auto-inhibitory helix from the active site entrance-way and promotion of a new conformational ensemble for the inter-domain, allosteric linker that has an active role in the catalytic cycle. We describe the evidence for close contact between membrane lipid, a compact allosteric linker, and the CCT active site, and discuss potential ways that this interaction enhances catalysis.
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Affiliation(s)
- Rosemary B Cornell
- Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada V5A-1S6.
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9
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Krishnan A, Kloehn J, Lunghi M, Soldati-Favre D. Vitamin and cofactor acquisition in apicomplexans: Synthesis versus salvage. J Biol Chem 2020; 295:701-714. [PMID: 31767680 PMCID: PMC6970920 DOI: 10.1074/jbc.aw119.008150] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The Apicomplexa phylum comprises diverse parasitic organisms that have evolved from a free-living ancestor. These obligate intracellular parasites exhibit versatile metabolic capabilities reflecting their capacity to survive and grow in different hosts and varying niches. Determined by nutrient availability, they either use their biosynthesis machineries or largely depend on their host for metabolite acquisition. Because vitamins cannot be synthesized by the mammalian host, the enzymes required for their synthesis in apicomplexan parasites represent a large repertoire of potential therapeutic targets. Here, we review recent advances in metabolic reconstruction and functional studies coupled to metabolomics that unravel the interplay between biosynthesis and salvage of vitamins and cofactors in apicomplexans. A particular emphasis is placed on Toxoplasma gondii, during both its acute and latent stages of infection.
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Affiliation(s)
- Aarti Krishnan
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva CMU, 1 Rue Michel-Servet, 1211 Geneva 4 Switzerland
| | - Joachim Kloehn
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva CMU, 1 Rue Michel-Servet, 1211 Geneva 4 Switzerland
| | - Matteo Lunghi
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva CMU, 1 Rue Michel-Servet, 1211 Geneva 4 Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva CMU, 1 Rue Michel-Servet, 1211 Geneva 4 Switzerland
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Krishnan A, Kloehn J, Lunghi M, Soldati-Favre D. Vitamin and cofactor acquisition in apicomplexans: Synthesis versus salvage. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49928-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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11
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Kita A, Kishimoto A, Shimosaka T, Tomita H, Yokooji Y, Imanaka T, Atomi H, Miki K. Crystal structure of pantoate kinase from Thermococcus kodakarensis. Proteins 2019; 88:718-724. [PMID: 31697438 DOI: 10.1002/prot.25852] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/29/2019] [Accepted: 11/03/2019] [Indexed: 11/09/2022]
Abstract
The coenzyme A biosynthesis pathways in most archaea involve two unique enzymes, pantoate kinase and phosphopantothenate synthetase, to convert pantoate to 4'-phosphopantothenate. Here, we report the first crystal structure of pantoate kinase from the hyperthermophilic archaeon, Thermococcus kodakarensis and its complex with ATP and a magnesium ion. The electron density for the adenosine moiety of ATP was very weak, which most likely relates to its broad nucleotide specificity. Based on the structure of the active site that contains a glycerol molecule, the pantoate binding site and the roles of the highly conserved residues are suggested.
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Affiliation(s)
- Akiko Kita
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka, Japan
| | - Asako Kishimoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Takahiro Shimosaka
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Hiroya Tomita
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Yuusuke Yokooji
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Tadayuki Imanaka
- Department of Biotechnology, College of Life Sciences, Ritsumeikan University, Kusatsu, Japan.,JST, CREST, Tokyo, Japan
| | - Haruyuki Atomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan.,JST, CREST, Tokyo, Japan
| | - Kunio Miki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan.,JST, CREST, Tokyo, Japan
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12
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Khanppnavar B, Chatterjee R, Choudhury GB, Datta S. Genome-wide survey and crystallographic analysis suggests a role for both horizontal gene transfer and duplication in pantothenate biosynthesis pathways. Biochim Biophys Acta Gen Subj 2019; 1863:1547-1559. [DOI: 10.1016/j.bbagen.2019.05.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 05/21/2019] [Accepted: 05/24/2019] [Indexed: 01/13/2023]
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13
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Gupta A, Singh PK, Sharma P, Kaur P, Sharma S, Singh TP. Structural and biochemical studies of phosphopantetheine adenylyltransferase from Acinetobacter baumannii with dephospho-coenzyme A and coenzyme A. Int J Biol Macromol 2019; 142:181-190. [PMID: 31525415 DOI: 10.1016/j.ijbiomac.2019.09.090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/11/2019] [Accepted: 09/11/2019] [Indexed: 11/29/2022]
Abstract
Phosphopantetheine adenylyl transferase catalyzes a rate limiting penultimate step of the multistep reaction which produces coenzyme A (CoA) as a final product. CoA is required as an essential cofactor in a number of metabolic reactions. Therefore inhibiting the function of this enzyme will lead to cell death in bacteria. Acinetobacter baumannii is multi drug resistant pathogen and causes infections in immunocompromised patients. AbPPAT has been cloned, expressed, purified and crystallized and structures of two complexes of AbPPAT with dephospho coenzyme A (dPCoA) and coenzyme A (CoA) have been determined. Both dPCoA and CoA molecules are observed in the substrate binding site of AbPPAT. A comparison with the structures of the complexes of PPAT from other species shows that the orientations of dPCoA are identical in all the structures. On the other hand, as observed from the structures of the complexes of CoA with PPAT, the orientations of CoA are found to differ considerably. This shows that the substrates occupy identical positions in the substrate binding sites of enzymes whereas the positions of inhibitors may differ. The binding studies carried out using fluorescence method and surface plasmon resonance techniques showed that binding affinity of CoA towards AbPPAT is nearly three times higher than that of dPCoA.
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Affiliation(s)
- A Gupta
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - P K Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - P Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - P Kaur
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - S Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - T P Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
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14
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Structural and binding studies of phosphopantetheine adenylyl transferase from Acinetobacter baumannii. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:537-547. [DOI: 10.1016/j.bbapap.2019.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 02/25/2019] [Accepted: 03/13/2019] [Indexed: 11/21/2022]
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15
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Lux MC, Standke LC, Tan DS. Targeting adenylate-forming enzymes with designed sulfonyladenosine inhibitors. J Antibiot (Tokyo) 2019; 72:325-349. [PMID: 30982830 PMCID: PMC6594144 DOI: 10.1038/s41429-019-0171-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 02/19/2019] [Accepted: 02/26/2019] [Indexed: 02/07/2023]
Abstract
Adenylate-forming enzymes are a mechanistic superfamily that are involved in diverse biochemical pathways. They catalyze ATP-dependent activation of carboxylic acid substrates as reactive acyl adenylate (acyl-AMP) intermediates and subsequent coupling to various nucleophiles to generate ester, thioester, and amide products. Inspired by natural products, acyl sulfonyladenosines (acyl-AMS) that mimic the tightly bound acyl-AMP reaction intermediates have been developed as potent inhibitors of adenylate-forming enzymes. This simple yet powerful inhibitor design platform has provided a wide range of biological probes as well as several therapeutic lead compounds. Herein, we provide an overview of the nine structural classes of adenylate-forming enzymes and examples of acyl-AMS inhibitors that have been developed for each.
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Affiliation(s)
- Michaelyn C Lux
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Lisa C Standke
- Pharmacology Graduate Program, Weill Cornell Graduate School of Medical Sciences, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Derek S Tan
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA. .,Pharmacology Graduate Program, Weill Cornell Graduate School of Medical Sciences, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA. .,Chemical Biology Program, Sloan Kettering Institute, and Tri-Institutional Research Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.
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16
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Semanjski M, Germain E, Bratl K, Kiessling A, Gerdes K, Macek B. The kinases HipA and HipA7 phosphorylate different substrate pools in
Escherichia coli
to promote multidrug tolerance. Sci Signal 2018; 11. [DOI: 10.1126/scisignal.aat5750] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Differences in the targets of HipA and its variant HipA7 may explain why these kinases have different effects on bacterial persistence.
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Affiliation(s)
- Maja Semanjski
- Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany
| | - Elsa Germain
- Centre for Bacterial Stress Response and Persistence, Department of Biology, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Katrin Bratl
- Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany
| | - Andreas Kiessling
- Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany
| | - Kenn Gerdes
- Centre for Bacterial Stress Response and Persistence, Department of Biology, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Boris Macek
- Proteome Center Tuebingen, Interfaculty Institute for Cell Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany
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17
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High throughput screening against pantothenate synthetase identifies amide inhibitors against Mycobacterium tuberculosis and Staphylococcus aureus. In Silico Pharmacol 2018; 6:9. [PMID: 30607322 DOI: 10.1007/s40203-018-0046-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 04/10/2018] [Indexed: 01/14/2023] Open
Abstract
Abstract Pantothenate is a crucial enzyme for the synthesis of coenzyme A and acyl carrier protein in Mycobacterium tuberculosis and Staphylococcus aureus. It is indispensable for the growth and survival of these bacteria. Amides analogs are designed and have been used as inhibitors of pantothenate synthetase. Molecular docking approach has been used to design and predict the drug activity of molecule to the specific disease. In this work, more than hundred amides have been screened by Discovery Studio molecular docking programme to search best suitable molecule for the treatment of Mycobacterium tuberculosis. Pharmacophore generation has been done to recognize the binding modes of inhibitors in the receptor active site. To observe the stability and flexibility of inhibitors molecular dynamics (MD) simulation has been done; Lipinski's rule of five protocols is followed to screen drug likeness and ADMET (absorption, distribution, metabolism, excretion and toxicity) filtration is also used to value toxicity. DFT computation of optimized geometry and derivation of MOs has been used to correlate the drug likeness. The small difference in energy between HOMO and LUMO may help to activate the drug in the protein environment quickly. 2-Hydroxy-5-[(E)-2-{4-[(prop-2-enamido)sulfonyl]phenyl}diazen-1-yl]benzoic acid (M1) shows best theoretical efficiency against Mycobacterium tuberculosis (MTB) pantothenate synthetase and so does 2-hydroxy-5-[(E)-2-{4-[(2-phenylacetamido)sulfonyl]phenyl}diazen-1-yl]benzoic acid (M2) against Staphylococcus aureus pantothenate synthetase. These compounds also bind to Adenine-Thymine region of tuberculosis DNA. Graphical abstract
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18
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Pandey B, Grover S, Goyal S, Kumari A, Singh A, Jamal S, Kaur J, Grover A. Alanine mutation of the catalytic sites of Pantothenate Synthetase causes distinct conformational changes in the ATP binding region. Sci Rep 2018; 8:903. [PMID: 29343701 PMCID: PMC5772511 DOI: 10.1038/s41598-017-19075-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 12/19/2017] [Indexed: 02/01/2023] Open
Abstract
The enzyme Pantothenate synthetase (PS) represents a potential drug target in Mycobacterium tuberculosis. Its X-ray crystallographic structure has demonstrated the significance and importance of conserved active site residues including His44, His47, Asn69, Gln72, Lys160 and Gln164 in substrate binding and formation of pantoyl adenylate intermediate. In the current study, molecular mechanism of decreased affinity of the enzyme for ATP caused by alanine mutations was investigated using molecular dynamics (MD) simulations and free energy calculations. A total of seven systems including wild-type + ATP, H44A + ATP, H47A + ATP, N69A + ATP, Q72A + ATP, K160A + ATP and Q164A + ATP were subjected to 50 ns MD simulations. Docking score, MM-GBSA and interaction profile analysis showed weak interactions between ATP (substrate) and PS (enzyme) in H47A and H160A mutants as compared to wild-type, leading to reduced protein catalytic activity. However, principal component analysis (PCA) and free energy landscape (FEL) analysis revealed that ATP was strongly bound to the catalytic core of the wild-type, limiting its movement to form a stable complex as compared to mutants. The study will give insight about ATP binding to the PS at the atomic level and will facilitate in designing of non-reactive analogue of pantoyl adenylate which will act as a specific inhibitor for PS.
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Affiliation(s)
- Bharati Pandey
- Department of Biotechnology, Panjab University, Chandigarh, 160014, India
| | - Sonam Grover
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi, 110016, India
| | - Sukriti Goyal
- Department of Bioscience and Biotechnology, Banasthali University, Tonk, Rajasthan, 304022, India
| | - Anchala Kumari
- Department of Biotechnology, TERI University, VasantKunj, New Delhi, 110070, India
| | - Aditi Singh
- Department of Biotechnology, TERI University, VasantKunj, New Delhi, 110070, India
| | - Salma Jamal
- Department of Bioscience and Biotechnology, Banasthali University, Tonk, Rajasthan, 304022, India
| | - Jagdeep Kaur
- Department of Biotechnology, Panjab University, Chandigarh, 160014, India
| | - Abhinav Grover
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India.
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19
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de Oliveira Viana J, Scotti MT, Scotti L. Molecular Docking Studies in Multitarget Antitubercular Drug Discovery. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2018. [DOI: 10.1007/7653_2018_28] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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20
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Blundell TL. Protein crystallography and drug discovery: recollections of knowledge exchange between academia and industry. IUCRJ 2017; 4:308-321. [PMID: 28875019 PMCID: PMC5571795 DOI: 10.1107/s2052252517009241] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 06/20/2017] [Indexed: 05/19/2023]
Abstract
The development of structure-guided drug discovery is a story of knowledge exchange where new ideas originate from all parts of the research ecosystem. Dorothy Crowfoot Hodgkin obtained insulin from Boots Pure Drug Company in the 1930s and insulin crystallization was optimized in the company Novo in the 1950s, allowing the structure to be determined at Oxford University. The structure of renin was developed in academia, on this occasion in London, in response to a need to develop antihypertensives in pharma. The idea of a dimeric aspartic protease came from an international academic team and was discovered in HIV; it eventually led to new HIV antivirals being developed in industry. Structure-guided fragment-based discovery was developed in large pharma and biotechs, but has been exploited in academia for the development of new inhibitors targeting protein-protein interactions and also antimicrobials to combat mycobacterial infections such as tuberculosis. These observations provide a strong argument against the so-called 'linear model', where ideas flow only in one direction from academic institutions to industry. Structure-guided drug discovery is a story of applications of protein crystallography and knowledge exhange between academia and industry that has led to new drug approvals for cancer and other common medical conditions by the Food and Drug Administration in the USA, as well as hope for the treatment of rare genetic diseases and infectious diseases that are a particular challenge in the developing world.
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Affiliation(s)
- Tom L. Blundell
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, England
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21
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Jakubowski H. Homocysteine Editing, Thioester Chemistry, Coenzyme A, and the Origin of Coded Peptide Synthesis †. Life (Basel) 2017; 7:life7010006. [PMID: 28208756 PMCID: PMC5370406 DOI: 10.3390/life7010006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 02/03/2017] [Indexed: 12/22/2022] Open
Abstract
Aminoacyl-tRNA synthetases (AARSs) have evolved “quality control” mechanisms which prevent tRNA aminoacylation with non-protein amino acids, such as homocysteine, homoserine, and ornithine, and thus their access to the Genetic Code. Of the ten AARSs that possess editing function, five edit homocysteine: Class I MetRS, ValRS, IleRS, LeuRS, and Class II LysRS. Studies of their editing function reveal that catalytic modules of these AARSs have a thiol-binding site that confers the ability to catalyze the aminoacylation of coenzyme A, pantetheine, and other thiols. Other AARSs also catalyze aminoacyl-thioester synthesis. Amino acid selectivity of AARSs in the aminoacyl thioesters formation reaction is relaxed, characteristic of primitive amino acid activation systems that may have originated in the Thioester World. With homocysteine and cysteine as thiol substrates, AARSs support peptide bond synthesis. Evolutionary origin of these activities is revealed by genomic comparisons, which show that AARSs are structurally related to proteins involved in coenzyme A/sulfur metabolism and non-coded peptide bond synthesis. These findings suggest that the extant AARSs descended from ancestral forms that were involved in non-coded Thioester-dependent peptide synthesis, functionally similar to the present-day non-ribosomal peptide synthetases.
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Affiliation(s)
- Hieronim Jakubowski
- Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ 07103, USA.
- Department of Biochemistry and Biotechnology, University of Life Sciences, Poznan 60-632, Poland.
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22
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Morrison PM, Balmforth MR, Ness SW, Williamson DJ, Rugen MD, Turnbull WB, Webb ME. Confirmation of a Protein-Protein Interaction in the Pantothenate Biosynthetic Pathway by Using Sortase-Mediated Labelling. Chembiochem 2016; 17:753-8. [PMID: 26818742 PMCID: PMC5963676 DOI: 10.1002/cbic.201500547] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Indexed: 01/29/2023]
Abstract
High-throughput studies have been widely used to identify protein-protein interactions; however, few of these candidate interactions have been confirmed in vitro. We have used a combination of isothermal titration calorimetry and fluorescence anisotropy to screen candidate interactions within the pantothenate biosynthetic pathway. In particular, we observed no interaction between the next enzyme in the pathway, pantothenate synthetase (PS), and aspartate decarboxylase, but did observe an interaction between PS and the putative Nudix hydrolase, YfcD. Confirmation of the interaction by fluorescence anisotropy was dependent upon labelling an adventitiously formed glycine on the protein N-terminal affinity purification tag by using Sortase. Subsequent formation of the protein-protein complex led to apparent restriction of the dynamics of this tag, thus suggesting that this approach could be generally applied to a subset of other protein-protein interaction complexes.
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Affiliation(s)
- Philip M Morrison
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Matthew R Balmforth
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Samuel W Ness
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Daniel J Williamson
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Michael D Rugen
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
- John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - W Bruce Turnbull
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Michael E Webb
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.
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23
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Jakubowski H. Aminoacyl-tRNA synthetases and the evolution of coded peptide synthesis: the Thioester World. FEBS Lett 2016; 590:469-81. [PMID: 26831912 DOI: 10.1002/1873-3468.12085] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 01/12/2016] [Accepted: 01/13/2016] [Indexed: 11/10/2022]
Abstract
Coded peptide synthesis must have been preceded by a prebiotic stage, in which thioesters played key roles. Fossils of the Thioester World are found in extant aminoacyl-tRNA synthetases (AARSs). Indeed, studies of the editing function reveal that AARSs have a thiol-binding site in their catalytic modules. The thiol-binding site confers the ability to catalyze aminoacyl~coenzyme A thioester synthesis and peptide bond formation. Genomic comparisons show that AARSs are structurally related to proteins involved in sulfur and coenzyme A metabolisms and peptide bond synthesis. These findings point to the origin of the amino acid activation and peptide bond synthesis functions in the Thioester World and suggest that the present-day AARSs had originated from ancestral forms that were involved in noncoded thioester-dependent peptide synthesis.
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Affiliation(s)
- Hieronim Jakubowski
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers-New Jersey Medical School, International Center for Public Health, Newark, NJ, USA.,Institute of Bioorganic Chemistry, Poznań, Poland.,Department of Biochemistry and Biotechnology, University of Life Sciences, Poznań, Poland
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24
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Conserved biosynthetic pathways for phosalacine, bialaphos and newly discovered phosphonic acid natural products. J Antibiot (Tokyo) 2015; 69:15-25. [PMID: 26328935 PMCID: PMC4731264 DOI: 10.1038/ja.2015.77] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 05/14/2015] [Accepted: 06/15/2015] [Indexed: 12/03/2022]
Abstract
Natural products containing phosphonic or phosphinic acid functionalities often display potent biological activities with applications in medicine and agriculture. The herbicide phosphinothricin-tripeptide (PTT) was the first phosphinate natural product discovered, yet despite numerous studies, questions remain surrounding key transformations required for its biosynthesis. In particular, the enzymology required to convert phosphonoformate to carboxyphosphonoenolpyruvate and the mechanisms underlying phosphorus-methylation remain poorly understood. In addition, the model for NRPS assembly of the intact tripeptide product has undergone numerous revisions that have yet to be experimentally tested. To further investigate the biosynthesis of this unusual natural product, we completely sequenced the PTT biosynthetic locus from Streptomyces hygroscopicus and compared it to the orthologous cluster from Streptomyces viridochromogenes. We also sequenced and analysed the closely related phosalacine (PAL) biosynthetic locus from Kitasatospora phosalacinea. Using data drawn from the comparative analysis of the PTT and PAL pathways, we also evaluate three related recently discovered phosphonate biosynthetic loci from Streptomyces sviceus, Streptomyces sp. WM6386 and Frankia alni. Our observations address long-standing biosynthetic questions related to PTT and PAL production and suggest that additional members of this pharmacologically important class await discovery.
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25
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Pantothenic acid biosynthesis in the parasite Toxoplasma gondii: a target for chemotherapy. Antimicrob Agents Chemother 2014; 58:6345-53. [PMID: 25049241 DOI: 10.1128/aac.02640-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is a major food pathogen and neglected parasitic infection that causes eye disease, birth defects, and fetal abortion and plays a role as an opportunistic infection in AIDS. In this study, we investigated pantothenic acid (vitamin B5) biosynthesis in T. gondii. Genes encoding the full repertoire of enzymes for pantothenate synthesis and subsequent metabolism to coenzyme A were identified and are expressed in T. gondii. A panel of inhibitors developed to target Mycobacterium tuberculosis pantothenate synthetase were tested and found to exhibit a range of values for inhibition of T. gondii growth. Two inhibitors exhibited lower effective concentrations than the currently used toxoplasmosis drug pyrimethamine. The inhibition was specific for the pantothenate pathway, as the effect of the pantothenate synthetase inhibitors was abrogated by supplementation with pantothenate. Hence, T. gondii encodes and expresses the enzymes for pantothenate synthesis, and this pathway is essential for parasite growth. These promising findings increase our understanding of growth and metabolism in this important parasite and highlight pantothenate synthetase as a new drug target.
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26
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Kishimoto A, Kita A, Ishibashi T, Tomita H, Yokooji Y, Imanaka T, Atomi H, Miki K. Crystal structure of phosphopantothenate synthetase from Thermococcus kodakarensis. Proteins 2014; 82:1924-36. [PMID: 24638914 DOI: 10.1002/prot.24546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 02/21/2014] [Accepted: 02/25/2014] [Indexed: 11/07/2022]
Abstract
Bacteria/eukaryotes share a common pathway for coenzyme A biosynthesis which involves two enzymes to convert pantoate to 4'-phosphopantothenate. These two enzymes are absent in almost all archaea. Recently, it was reported that two novel enzymes, pantoate kinase, and phosphopantothenate synthetase (PPS), are responsible for this conversion in archaea. Here, we report the crystal structure of PPS from the hyperthermophilic archaeon, Thermococcus kodakarensis and its complexes with substrates, ATP, and ATP and 4-phosphopantoate. PPS forms an asymmetric homodimer, in which two monomers composing a dimer, deviated from the exact twofold symmetry, displaying 4°-13° distortion. The structural features are consistent with the mutagenesis data and the results of biochemical experiments previously reported. Based on these structures, we discuss the catalytic mechanism by which PPS produces phosphopantoyl adenylate, which is thought to be a reaction intermediate.
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Affiliation(s)
- Asako Kishimoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
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27
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Kim MK, An YJ, Cha SS. The crystal structure of a novel phosphopantothenate synthetase from the hyperthermophilic archaea, Thermococcus onnurineus NA1. Biochem Biophys Res Commun 2013; 439:533-8. [PMID: 24021277 DOI: 10.1016/j.bbrc.2013.09.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 09/02/2013] [Indexed: 11/18/2022]
Abstract
Pantothenate is the essential precursor of coenzyme A (CoA), a fundamental cofactor in all aspects of metabolism. In bacteria and eukaryotes, pantothenate synthetase (PS) catalyzes the last step in the pantothenate biosynthetic pathway, and pantothenate kinase (PanK) phosphorylates pantothenate for its entry into the CoA biosynthetic pathway. However, genes encoding PS and PanK have not been identified in archaeal genomes. Recently, a comparative genomic analysis and the identification and characterization of two novel archaea-specific enzymes show that archaeal pantoate kinase (PoK) and phosphopantothenate synthetase (PPS) represent counterparts to the PS/PanK pathway in bacteria and eukaryotes. The TON1374 protein from Thermococcus onnurineus NA1 is a PPS, that shares 54% sequence identity with the first reported archaeal PPS candidate, MM2281, from Methanosarcina mazei and 91% sequence identity with TK1686, the PPS from Thermococcus kodakarensis. Here, we report the apo and ATP-complex structures of TON1374 and discuss the substrate-binding mode and reaction mechanism.
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Affiliation(s)
- Min-Kyu Kim
- Marine Biotechnology Research Division, Korea Institute of Ocean Science and Technology, Ansan 426-744, Republic of Korea
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28
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A detailed biochemical characterization of phosphopantothenate synthetase, a novel enzyme involved in coenzyme A biosynthesis in the Archaea. Extremophiles 2012; 16:819-28. [PMID: 22940806 DOI: 10.1007/s00792-012-0477-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 08/16/2012] [Indexed: 10/27/2022]
Abstract
We have previously reported that the majority of the archaea utilize a novel pathway for coenzyme A biosynthesis (CoA). Bacteria/eukaryotes commonly use pantothenate synthetase and pantothenate kinase to convert pantoate to 4'-phosphopantothenate. However, in the hyperthermophilic archaeon Thermococcus kodakarensis, two novel enzymes specific to the archaea, pantoate kinase and phosphopantothenate synthetase, are responsible for this conversion. Here, we examined the enzymatic properties of the archaeal phosphopantothenate synthetase, which catalyzes the ATP-dependent condensation of 4-phosphopantoate and β-alanine. The activation energy of the phosphopantothenate synthetase reaction was 82.3 kJ mol(-1). In terms of substrate specificity toward nucleoside triphosphates, the enzyme displayed a strict preference for ATP. Among several amine substrates, activity was detected with β-alanine, but not with γ-aminobutyrate, glycine nor aspartate. The phosphopantothenate synthetase reaction followed Michaelis-Menten kinetics toward β-alanine, whereas substrate inhibition was observed with 4-phosphopantoate and ATP. Feedback inhibition by CoA/acetyl-CoA and product inhibition by 4'-phosphopantothenate were not observed. By contrast, the other archaeal enzyme pantoate kinase displayed product inhibition by 4-phosphopantoate in a non-competitive manner. Based on our results, we discuss the regulation of CoA biosynthesis in the archaea.
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29
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The phylogenomic roots of modern biochemistry: origins of proteins, cofactors and protein biosynthesis. J Mol Evol 2012; 74:1-34. [PMID: 22210458 DOI: 10.1007/s00239-011-9480-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 12/12/2011] [Indexed: 12/20/2022]
Abstract
The complexity of modern biochemistry developed gradually on early Earth as new molecules and structures populated the emerging cellular systems. Here, we generate a historical account of the gradual discovery of primordial proteins, cofactors, and molecular functions using phylogenomic information in the sequence of 420 genomes. We focus on structural and functional annotations of the 54 most ancient protein domains. We show how primordial functions are linked to folded structures and how their interaction with cofactors expanded the functional repertoire. We also reveal protocell membranes played a crucial role in early protein evolution and show translation started with RNA and thioester cofactor-mediated aminoacylation. Our findings allow elaboration of an evolutionary model of early biochemistry that is firmly grounded in phylogenomic information and biochemical, biophysical, and structural knowledge. The model describes how primordial α-helical bundles stabilized membranes, how these were decorated by layered arrangements of β-sheets and α-helices, and how these arrangements became globular. Ancient forms of aminoacyl-tRNA synthetase (aaRS) catalytic domains and ancient non-ribosomal protein synthetase (NRPS) modules gave rise to primordial protein synthesis and the ability to generate a code for specificity in their active sites. These structures diversified producing cofactor-binding molecular switches and barrel structures. Accretion of domains and molecules gave rise to modern aaRSs, NRPS, and ribosomal ensembles, first organized around novel emerging cofactors (tRNA and carrier proteins) and then more complex cofactor structures (rRNA). The model explains how the generation of protein structures acted as scaffold for nucleic acids and resulted in crystallization of modern translation.
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30
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Tan YS, Fuentes G, Verma C. A comparison of the dynamics of pantothenate synthetase from M. tuberculosis and E. coli: computational studies. Proteins 2011; 79:1715-27. [PMID: 21425349 DOI: 10.1002/prot.22994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 11/24/2010] [Accepted: 12/15/2010] [Indexed: 11/11/2022]
Abstract
Pantothenate synthetase (PS) catalyzes the final step of the pantothenate pathway, in which pantothenate is formed from pantoate and β-alanine in an ATP-dependent reaction. Mycobacterium tuberculosis PS (MTB PS) is functionally a dimer and a potential target for novel antitubercular drugs. Molecular dynamics simulations show that the functional dynamics of the enzyme are dominated by motions of a flexible gate loop in the N-terminal domain and of the C-terminal domain. The gate loop motions dominate in MTB PS while the C-terminal domain motion dominates in Escherichia coli PS. Simulations also show that the correlated motions of the domains are severely compromised in the monomeric forms. Mutations that reduce the mobility of the gate loop in MTB PS and increased it in E. coli PS were designed and validated through simulations.
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Affiliation(s)
- Yaw Sing Tan
- Bioinformatics Institute, A*STAR, 30 Biopolis Street, #07-01 Matrix, Singapore 138671
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31
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Satoh A, Konishi S, Tamura H, Stickland HG, Whitney HM, Smith AG, Matsumura H, Inoue T. Substrate-Induced Closing of the Active Site Revealed by the Crystal Structure of Pantothenate Synthetase from Staphylococcus aureus. Biochemistry 2010; 49:6400-10. [DOI: 10.1021/bi1004206] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Atsuko Satoh
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Saki Konishi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Haruka Tamura
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hannah G. Stickland
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, United Kingdom
| | - Heather M. Whitney
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, United Kingdom
| | - Alison G. Smith
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, United Kingdom
| | - Hiroyoshi Matsumura
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- CREST, JST, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Tsuyoshi Inoue
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- CREST, JST, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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Chakrabarti KS, Thakur KG, Gopal B, Sarma SP. X-ray crystallographic and NMR studies of pantothenate synthetase provide insights into the mechanism of homotropic inhibition by pantoate. FEBS J 2010; 277:697-712. [PMID: 20059543 DOI: 10.1111/j.1742-4658.2009.07515.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The structural basis for the homotropic inhibition of pantothenate synthetase by the substrate pantoate was investigated by X-ray crystallography and high-resolution NMR spectroscopic methods. The tertiary structure of the dimeric N-terminal domain of Escherichia coli pantothenate synthetase, determined by X-ray crystallography to a resolution of 1.7 A, showed a second molecule of pantoate bound in the ATP-binding pocket. Pantoate binding to the ATP-binding site induced large changes in structure, mainly for backbone and side chain atoms of residues in the ATP binding HXGH(34-37) motif. Sequence-specific NMR resonance assignments and solution secondary structure of the dimeric N-terminal domain, obtained using samples enriched in (2)H, (13)C, and (15)N, indicated that the secondary structural elements were conserved in solution. Nitrogen-15 edited two-dimensional solution NMR chemical shift mapping experiments revealed that pantoate, at 10 mm, bound at these two independent sites. The solution NMR studies unambiguously demonstrated that ATP stoichiometrically displaced pantoate from the ATP-binding site. All NMR and X-ray studies were conducted at substrate concentrations used for enzymatic characterization of pantothenate synthetase from different sources [Jonczyk R & Genschel U (2006) J Biol Chem 281, 37435-37446]. As pantoate binding to its canonical site is structurally conserved, these results demonstrate that the observed homotropic effects of pantoate on pantothenate biosynthesis are caused by competitive binding of this substrate to the ATP-binding site. The results presented here have implications for the design and development of potential antibacterial and herbicidal agents.
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Fan F, Blanchard JS. Toward the catalytic mechanism of a cysteine ligase (MshC) from Mycobacterium smegmatis: an enzyme involved in the biosynthetic pathway of mycothiol. Biochemistry 2009; 48:7150-9. [PMID: 19505149 DOI: 10.1021/bi900457x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mycobacterium tuberculosis and other members of the actinomycete family produce mycothiol (MSH or acetylcysteine-glucosamine-inositol, AcCys-GlcN-Ins) to protect the organism against oxidative and antibiotic stress. The biosynthesis of MSH proceeds via a five-step process that involves four unique enzymes, MshA-D, which represent specific targets for inhibitor design. Recombinant Mycobacterium smegmatis MshC catalyzes the ATP-dependent condensation of glucosamine-inositol (GlcN-Ins) and cysteine to form Cys-GlcN-Ins. The 1.6 A three-dimensional structure of MshC in complex with a tight binding bisubstrate analogue, 5'-O-[N-(L-cysteinyl)sulfamonyl]adenosine (CSA), has suggested specific roles for T46, H55, T83, W227, and D251. In addition, a catalytic role for H55 has been proposed on the basis of studies of related aminoacyl-tRNA synthetases. Site-directed mutagenesis was conducted to evaluate the functional roles of these highly conserved residues. All mutants exhibited significantly decreased k(cat) values, with the exception of T83V for which a <7-fold decrease was observed compared to that of the wild type (WT). For the T46V, H55A, W227F, and D251N mutants, the rate of cysteine activation decreased 100-1400-fold compared to that of WT, consistent with the important roles of these residues in the first half-reaction. The approximately 2000-fold decrease in k(cat)/K(m) as well as the approximately 20-fold decrease in K(m) for cysteine suggested a significant role for T46 in cysteine binding. Kinetic studies also indicate a function for W227 in cysteine binding but not in substrate discrimination against serine. H55 was also observed to play a significant role in ATP binding as well as cysteine adenylation. The activity of H55A was partially rescued with exogenous imidazole at acidic pH values, suggesting that the protonated form of histidine is exerting a catalytic role. The pH dependence of the kinetic parameters with the WT enzyme suggests an additional requirement for a catalytic base in cysteinyl ligation.
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Affiliation(s)
- Fan Fan
- Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, USA
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34
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Fragment-Based Drug Discovery in Academia: Experiences From a Tuberculosis Programme. NATO SCIENCE FOR PEACE AND SECURITY SERIES A: CHEMISTRY AND BIOLOGY 2009. [DOI: 10.1007/978-90-481-2339-1_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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35
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Chakauya E, Coxon KM, Wei M, Macdonald MV, Barsby T, Abell C, Smith AG. Towards engineering increased pantothenate (vitamin B(5)) levels in plants. PLANT MOLECULAR BIOLOGY 2008; 68:493-503. [PMID: 18726075 DOI: 10.1007/s11103-008-9386-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Accepted: 07/31/2008] [Indexed: 05/26/2023]
Abstract
Pantothenate (vitamin B(5)) is the precursor of the 4'-phosphopantetheine moiety of coenzyme A and acyl-carrier protein. It is made by plants and microorganisms de novo, but is a dietary requirement for animals. The pantothenate biosynthetic pathway is well-established in bacteria, comprising four enzymic reactions catalysed by ketopantoate hydroxymethyltransferase (KPHMT), L: -aspartate-alpha-decarboxylase (ADC), pantothenate synthetase (PS) and ketopantoate reductase (KPR) encoded by panB, panD, panC and panE genes, respectively. In higher plants, the genes encoding the first (KPHMT) and last (PS) enzymes have been identified and characterised in several plant species. Commercially, pantothenate is chemically synthesised and used in vitamin supplements, feed additives and cosmetics. Biotransformation is an attractive alternative production system that would circumvent the expensive procedures of separating racemic intermediates. We explored the possibility of manipulating pantothenate biosynthesis in plants. Transgenic oilseed rape (Brassica napus) lines were generated in which the E. coli KPHMT and PS genes were expressed under a strong constitutive CaMV35SS promoter. No significant change of pantothenate levels in PS transgenic lines was observed. In contrast plants expressing KPHMT had elevated pantothenate levels in leaves, flowers siliques and seed in the range of 1.5-2.5 fold increase compared to the wild type plant. Seeds contained the highest vitamin content, indicating that they might be the ideal target for production purposes.
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Affiliation(s)
- Ereck Chakauya
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
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36
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Abstract
The linear biosynthetic pathway leading from alpha-ketoisovalerate to pantothenate (vitamin B5) and on to CoA comprises eight steps in the Bacteria and Eukaryota. Genes for up to six steps of this pathway can be identified by sequence homology in individual archaeal genomes. However, there are no archaeal homologs to known isoforms of pantothenate synthetase (PS) or pantothenate kinase. Using comparative genomics, we previously identified two conserved archaeal protein families as the best candidates for the missing steps. Here we report the characterization of the predicted PS gene from Methanosarcina mazei, which encodes a hypothetical protein (MM2281) with no obvious homologs outside its own family. When expressed in Escherichia coli, MM2281 partially complemented an auxotrophic mutant without PS activity. Purified recombinant MM2281 showed no PS activity on its own, but the enzyme enabled substantial synthesis of [14C]4'-phosphopantothenate from [14C]beta-alanine, pantoate and ATP when coupled with E. coli pantothenate kinase. ADP, but not AMP, was detected as a coproduct of the coupled reaction. MM2281 also transferred the 14C-label from [14C]beta-alanine to pantothenate in the presence of pantoate and ADP, presumably through isotope exchange. No exchange took place when pantoate was removed or ADP replaced with AMP. Our results indicate that MM2281 represents a novel type of PS that forms ADP and is strongly inhibited by its product pantothenate. These properties differ substantially from those of bacterial PS, and may explain why PS genes, in contrast to other pantothenate biosynthetic genes, were not exchanged horizontally between the Bacteria and Archaea.
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Affiliation(s)
- Silvia Ronconi
- Lehrstuhl für Genetik, Technische Universität München, Freising, Germany
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37
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Abstract
Pantothenic acid, a precursor of coenzyme A (CoA), is essential for the growth of pathogenic microorganisms. Since the structure of pantothenic acid was determined, many analogues of this essential metabolite have been prepared. Several have been demonstrated to exert an antimicrobial effect against a range of microorganisms by inhibiting the utilization of pantothenic acid, validating pantothenic acid utilization as a potential novel antimicrobial drug target. This review commences with an overview of the mechanisms by which various microorganisms acquire the pantothenic acid they require for growth, and the universal CoA biosynthesis pathway by which pantothenic acid is converted into CoA. A detailed survey of studies that have investigated the inhibitory activity of analogues of pantothenic acid and other precursors of CoA follows. The potential of inhibitors of both pantothenic acid utilization and biosynthesis as novel antibacterial, antifungal and antimalarial agents is discussed, focusing on inhibitors and substrates of pantothenate kinase, the enzyme catalysing the rate-limiting step of CoA biosynthesis in many organisms. The best strategies are considered for identifying inhibitors of pantothenic acid utilization and biosynthesis that are potent and selective inhibitors of microbial growth and that may be suitable for use as chemotherapeutic agents in humans.
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Affiliation(s)
- Christina Spry
- School of Biochemistry and Molecular Biology, The Australian National University, Canberra, Australia
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38
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Seetharamappa J, Oke M, Liu H, McMahon SA, Johnson KA, Carter L, Dorward M, Zawadzki M, Overton IM, van Niekirk CAJ, Graham S, Botting CH, Taylor GL, White MF, Barton GJ, Coote PJ, Naismith JH. Purification, crystallization and data collection of methicillin-resistant Staphylococcus aureus Sar2676, a pantothenate synthetase. Acta Crystallogr Sect F Struct Biol Cryst Commun 2007; 63:488-91. [PMID: 17554169 PMCID: PMC2335074 DOI: 10.1107/s1744309107020362] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2007] [Accepted: 04/24/2007] [Indexed: 11/10/2022]
Abstract
Sar2676, a pantothenate synthetase with a molecular weight of 31 419 Da from methicillin-resistant Staphylococcus aureus, has been expressed, purified and crystallized at 293 K. The protein crystallizes in a primitive triclinic lattice, with unit-cell parameters a = 45.3, b = 60.5, c = 117.6 A, alpha = 87.2, beta = 81.2, gamma = 68.4 degrees . A complete data set has been collected to 2.3 A resolution at the ESRF. Consideration of the likely solvent content suggested the asymmetric unit to contain four molecules. This has been confirmed by molecular-replacement phasing calculations, which give a solution with four monomers using a monomer of pantothenate synthetase from Escherichia coli (PDB code 1iho), which is 41% identical to Sar2676, as a search model.
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Affiliation(s)
- Jaldappagari Seetharamappa
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
- Department of Chemistry, Karnatak University, Pavate Nagar, Dharwad 580 003, Karnataka State, India
| | - Muse Oke
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Huanting Liu
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Stephen A. McMahon
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Kenneth A. Johnson
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Lester Carter
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Mark Dorward
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Michal Zawadzki
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Ian M. Overton
- Scottish Structural Facility and School of Life Sciences Research, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland
| | - C. A. Johannes van Niekirk
- Scottish Structural Facility and School of Life Sciences Research, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland
| | - Shirley Graham
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Catherine H. Botting
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Garry L. Taylor
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Malcolm F. White
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - Geoffrey J. Barton
- Scottish Structural Facility and School of Life Sciences Research, University of Dundee, Dow Street, Dundee DD1 5EH, Scotland
| | - Peter J. Coote
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
| | - James H. Naismith
- Scottish Structural Facility and Centre for Biomolecular Sciences, The University, St Andrews KY16 9ST, Scotland
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Holliday GL, Thornton JM, Marquet A, Smith AG, Rébeillé F, Mendel R, Schubert HL, Lawrence AD, Warren MJ. Evolution of enzymes and pathways for the biosynthesis of cofactors. Nat Prod Rep 2007; 24:972-87. [PMID: 17898893 DOI: 10.1039/b703107f] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The evolution of metabolic pathways is discussed with reference to the biosynthesis of a number of vitamins and cofactors. Retrograde and patchwork models are highlighted and their relevance to our knowledge of pathway processes and enzymes is examined. Pathway complexity is explained in terms of the acquisition of broad specificity enzymes.
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Affiliation(s)
- Gemma L Holliday
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, UK CB10 1SD.
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40
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Webb ME, Marquet A, Mendel RR, Rébeillé F, Smith AG. Elucidating biosynthetic pathways for vitamins and cofactors. Nat Prod Rep 2007; 24:988-1008. [PMID: 17898894 DOI: 10.1039/b703105j] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The elucidation of the pathways to the water-soluble vitamins and cofactors has provided many biochemical and chemical challenges. This is a reflection both of their complex chemical nature, and the fact that they are often made in small amounts, making detection of the enzyme activities and intermediates difficult. Here we present an orthogonal review of how these challenges have been overcome using a combination of methods, which are often ingenious. We make particular reference to some recent developments in the study of biotin, pantothenate, folate, pyridoxol, cobalamin, thiamine, riboflavin and molybdopterin biosynthesis.
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Affiliation(s)
- Michael E Webb
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK.
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41
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Jonczyk R, Genschel U. Molecular adaptation and allostery in plant pantothenate synthetases. J Biol Chem 2006; 281:37435-46. [PMID: 17040917 DOI: 10.1074/jbc.m607895200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pantothenate synthetase catalyzes the ATP-dependent condensation of pantoate and beta-alanine to yield pantothenate, the essential precursor to coenzyme A. Bacterial and plant pantothenate synthetases are dimeric enzymes that share significant sequence identity. Here we show that the two-step reaction mechanism of pantothenate synthetase is conserved between the enzymes from Arabidopsis thaliana and Escherichia coli. Strikingly, though, the Arabidopsis enzyme exhibits large allosteric effects, whereas the Escherichia coli enzyme displays essentially non-allosteric behavior. Our data suggest that specific subunit contacts were selected and maintained in the plant lineage of the pantothenate synthetase protein family and that the resulting allosteric interactions are balanced for efficient catalysis at low pantoate levels. This is supported by mutations in the putative subunit interface of Arabidopsis pantothenate synthetase, which strongly attenuated or otherwise modified its allosteric properties but did not affect the dimeric state of the enzyme. At the molecular level, plant pantothenate synthetases exemplify functional adaptation through allostery and without alterations to the active site architecture. We propose that the allosteric behavior confers a selective advantage in the context of the subcellular compartmentation of pantothenate biosynthesis in plants.
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Affiliation(s)
- Rafal Jonczyk
- Lehrstuhl für Genetik, Technische Universität München, 85350 Freising, Germany
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42
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Tuck KL, Saldanha SA, Birch LM, Smith AG, Abell C. The design and synthesis of inhibitors of pantothenate synthetase. Org Biomol Chem 2006; 4:3598-610. [PMID: 16990935 DOI: 10.1039/b609482a] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pantothenate synthetase catalyses the ATP-dependent condensation of D-pantoate and beta-alanine to form pantothenate. Ten analogues of the reaction intermediate pantoyl adenylate, in which the phosphodiester is replaced by either an ester or sulfamoyl group, were designed as potential inhibitors of the enzyme. The esters were all modest competitive inhibitors, the sulfamoyls were more potent, consistent with their closer structural similarity to the pantoyl adenylate intermediate.
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Affiliation(s)
- Kellie L Tuck
- University Chemical Laboratory, Lensfield Road, Cambridge, UK CB2 1EW
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43
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Coxon KM, Chakauya E, Ottenhof HH, Whitney HM, Blundell TL, Abell C, Smith AG. Pantothenate biosynthesis in higher plants. Biochem Soc Trans 2005; 33:743-6. [PMID: 16042590 DOI: 10.1042/bst0330743] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Pantothenate (vitamin B5) is a water-soluble vitamin essential for the synthesis of CoA and ACP (acyl-carrier protein, cofactors in energy yielding reactions including carbohydrate metabolism and fatty acid synthesis. Pantothenate is synthesized de novo by plants and micro-organisms; however, animals obtain the vitamin through their diet. Utilizing our knowledge of the pathway in Escherichia coli, we have discovered and cloned genes encoding the first and last enzymes of the pathway from Arabidopsis, panB1, panB2 and panC. It is unlikely that there is a homologue of the E. coli panD gene, therefore plants must make β-alanine by an alternative route. Possible candidates for the remaining gene, panE, are being investigated. GFP (green fluorescent protein) fusions of the three identified plant enzymes have been generated and the subcellular localization of the enzymes studied. Work is now being performed to elucidate expression patterns of the transcripts and characterize the proteins encoded by these genes.
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Affiliation(s)
- K M Coxon
- Department of Plant Sciences, Downing Street, Cambridge CB2 3EA, UK
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44
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Lee BI, Suh SW. Crystal structure of the schiff base intermediate prior to decarboxylation in the catalytic cycle of aspartate alpha-decarboxylase. J Mol Biol 2004; 340:1-7. [PMID: 15184017 DOI: 10.1016/j.jmb.2004.04.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2004] [Revised: 04/16/2004] [Accepted: 04/20/2004] [Indexed: 11/21/2022]
Abstract
l-Aspartate alpha-decarboxylase (ADC), encoded by the panD gene, catalyzes the conversion of l-aspartate into beta-alanine. In the microorganisms, beta-alanine is required for the synthesis of pantothenate (vitamin B(5)), which is the precursor of 4'-phosphopantetheine and coenzyme A. We have determined the crystal structure of Helicobacter pylori ADC, a tetrameric enzyme, in two forms: the apo structure at 2.0 A resolution and the isoasparagine complex structure at 1.55 A resolution. All subunits of the tetramer are self-processed at the Gly24-Ser25 linkage, producing the smaller beta chain (residues 1-24) and the larger alpha chain (residues 25-117). Each subunit contains nine beta-strands and three alpha-helices; it is folded into the double-psi beta-barrel structure. In the apo structure, the new amino terminus of the alpha chain, Ser25, is converted into a pyruvoyl group. In the isoasparagine complex structure, the substrate analog is covalently attached to the pyruvoyl group. This structure represents the enzyme-substrate Schiff base intermediate that was proposed to form prior to the decarboxylation step in the catalytic cycle of ADC. Thus our study provides direct structural evidence for the reaction mechanism of ADC.
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Affiliation(s)
- Byung Il Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 151-742, South Korea
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45
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Ottenhof HH, Ashurst JL, Whitney HM, Saldanha SA, Schmitzberger F, Gweon HS, Blundell TL, Abell C, Smith AG. Organisation of the pantothenate (vitamin B5) biosynthesis pathway in higher plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 37:61-72. [PMID: 14675432 DOI: 10.1046/j.1365-313x.2003.01940.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Pantothenate (vitamin B5) is the precursor for the biosynthesis of the phosphopantetheine moiety of coenzyme A and acyl carrier protein, and is synthesised in Escherichia coli by four enzymic reactions. Ketopantoate hydroxymethyltransferase (KPHMT) and pantothenate synthetase (PtS) catalyse the first and last steps, respectively. Two genes encoding KPHMT and one for PtS were identified in the Arabidopsis thaliana genome, and cDNAs for all three genes were amplified by PCR. The cDNAs were able to complement their respective E. coli auxotrophs, demonstrating that they encoded functional enzymes. Subcellular localisation of the proteins was investigated using green fluorescent protein (GFP) fusions and confocal microscopy. The two KPHMT-GFP fusion proteins were targeted exclusively to mitochondria, whereas PtS-GFP was found in the cytosol. This implies that there must be transporters for pathway intermediates. KPHMT enzyme activity could be measured in purified mitochondria from both pea leaves and Arabidopsis suspension cultures. We investigated whether Arabidopsis encoded homologues of the remaining two pantothenate biosynthesis enzymes from E. coli, l-aspartate-alpha-decarboxylase (ADC) and ketopantoate reductase (KPR). No homologue of ADC could be identified using either conventional blast or searches with the program fugue in which the structure of the E. coli ADC was compared to all the annotated proteins in Arabidopsis. ADC also appears to be absent from the genome of the yeast, Saccharomyces cerevisiae, by the same criteria. In contrast, a putative Arabidopsis oxidoreductase with some similarity to KPR was identified with fugue.
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46
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Lai CY, Cronan JE. β-Ketoacyl-Acyl Carrier Protein Synthase III (FabH) Is Essential for Bacterial Fatty Acid Synthesis. J Biol Chem 2003; 278:51494-503. [PMID: 14523010 DOI: 10.1074/jbc.m308638200] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
beta-Ketoacyl-acyl carrier protein (ACP) synthase III (KAS III, also called acetoacetyl-ACP synthase) encoded by the fabH gene is thought to catalyze the first elongation reaction (Claisen condensation) of type II fatty acid synthesis in bacteria and plant plastids. However, direct in vivo evidence that KAS III catalyzes an essential reaction is lacking, because no mutant organism deficient in this activity has been isolated. We report the first bacterial strain lacking KAS III, a fabH mutant constructed in the Gram-positive bacterium Lactococcus lactis subspecies lactis IL1403. The mutant strain carries an in-frame deletion of the KAS III active site region and was isolated by gene replacement using a medium supplemented with a source of saturated and unsaturated long-chain fatty acids. The mutant strain is devoid of KAS III activity and fails to grow in the absence of supplementation with exogenous long-chain fatty acids demonstrating that KAS III plays an essential role in cellular metabolism. However, the L. lactis fabH deletion mutant requires only long-chain unsaturated fatty acids for growth, a source of long-chain saturated fatty acids is not required. Because both saturated and unsaturated fatty acids are required for growth when fatty acid synthesis is blocked by biotin starvation (which prevents the synthesis of malonyl-CoA), another pathway for saturated fatty acid synthesis must remain in the fabH deletion strain. Indeed, incorporation of [1-14C]acetate into fatty acids in vivo showed that the fabH mutant retained about 10% of the fatty acid synthetic ability of the wild-type strain and that this residual synthetic capacity was preferentially diverted to the saturated branch of the pathway. Moreover, mass spectrometry showed that the fabH mutant retained low levels of palmitic acid upon fatty acid starvation. Derivatives of the fabH deletion mutant strain were isolated that were octanoic acid auxotrophs consistent with biochemical studies indicating that the major role of FabH is production of short-chain fatty acid primers. We also confirmed the essentiality of FabH in Escherichia coli by use of a plasmid-based gene insertion/deletion system. Together these results provide the first genetic evidence demonstrating that FabH conducts the major condensation reaction in the initiation of type II fatty acid biosynthesis in both Gram-positive and Gram-negative bacteria.
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Affiliation(s)
- Chiou-Yan Lai
- Department of Microbiology and Biochemistry, University of Illinois, Urbana, Illinois 61801, USA
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47
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Saridakis V, Pai EF. Mutational, structural, and kinetic studies of the ATP-binding site of Methanobacterium thermoautotrophicum nicotinamide mononucleotide adenylyltransferase. J Biol Chem 2003; 278:34356-63. [PMID: 12810729 DOI: 10.1074/jbc.m205369200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Several residues lining the ATP-binding site of Methanobacterium thermoautotrophicum nicotinamide mononucleotide adenylyltransferase (NMNATase) were mutated in an effort to better characterize their roles in substrate binding and catalysis. Residues selected were Arg-11 and Arg-136, both of which had previously been implicated as substrate binding residues, as well as His-16 and His-19, part of the HXGH active site motif and postulated to be of importance in catalysis. Kinetic studies revealed that both Arg-11 and Arg-136 contributed to the binding of the substrate, ATP. When these amino acids were replaced by lysines, the apparent Km values of the respective mutants for ATP decreased by factors of 1.3 and 2.9 and by factors of 1.9 and 8.8 when the same residues were changed to alanines. All four Arg mutants displayed unaltered Km values for NMN. The apparent kcat values of the R11K and R136K mutants were the same as those of WT NMNATase but the apparent kcat values of the alanine mutants had decreased. Crystal structures of the Arg mutants revealed NAD+ and SO42- molecules trapped at their active sites. The binding interactions of NAD+ were unchanged but the binding of SO42- was altered in these mutants compared with wild type. The alanine mutants at positions His-16 and His-19 retained approximately 6 and 1.3%, respectively, of WT NMNATase activity indicating that His-19 is a key catalytic group. Surprisingly, this H19A mutant displayed a novel and distinct mode of NAD+ binding when co-crystallized in the presence of NAD+ and SO42-.
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Affiliation(s)
- Vivian Saridakis
- Molecular and Structural Biology, Ontario Cancer Institute, University Health Network, and the Department of Medical Biophysics, University of Toronto, Ontario, Canada
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Manoj N, Strauss E, Begley TP, Ealick SE. Structure of human phosphopantothenoylcysteine synthetase at 2.3 A resolution. Structure 2003; 11:927-36. [PMID: 12906824 DOI: 10.1016/s0969-2126(03)00146-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The structure of human phosphopantothenoylcysteine (PPC) synthetase was determined at 2.3 A resolution. PPC synthetase is a dimer with identical monomers. Some features of the monomer fold resemble a group of NAD-dependent enzymes, while other features resemble the ribokinase fold. The ATP, phosphopantothenate, and cysteine binding sites were deduced from modeling studies. Highly conserved ATP binding residues include Gly43, Ser61, Gly63, Gly66, Phe230, and Asn258. Highly conserved phosphopantothenate binding residues include Asn59, Ala179, Ala180, and Asp183 from one monomer and Arg55' from the adjacent monomer. The structure predicts a ping pong mechanism with initial formation of an acyladenylate intermediate, followed by release of pyrophosphate and attack by cysteine to form the final products PPC and AMP.
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Affiliation(s)
- Narayanan Manoj
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
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49
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von Delft F, Inoue T, Saldanha SA, Ottenhof HH, Schmitzberger F, Birch LM, Dhanaraj V, Witty M, Smith AG, Blundell TL, Abell C. Structure of E. coli ketopantoate hydroxymethyl transferase complexed with ketopantoate and Mg2+, solved by locating 160 selenomethionine sites. Structure 2003; 11:985-96. [PMID: 12906829 DOI: 10.1016/s0969-2126(03)00158-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We report the crystal structure of E. coli ketopantoate hydroxymethyltransferase (KPHMT) at 1.9 A resolution, in complex with its product, ketopantoate. KPHMT catalyzes the first step in the biosynthesis of pantothenate (vitamin B(5)), the precursor of coenzyme A and the acyl carrier protein cofactor. The structure of the decameric enzyme was solved by multiwavelength anomalous dispersion to locate 160 selenomethionine sites and phase 560 kDa of protein, making it the largest structure solved by this approach. KPHMT adopts the (betaalpha)(8) barrel fold and is a member of the phosphoenolpyruvate/pyruvate superfamily. The active site contains a ketopantoate bidentately coordinated to Mg(2+). Similar binding is likely for the substrate, alpha-ketoisovalerate, orienting the C3 for deprotonation.
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Affiliation(s)
- Frank von Delft
- Department of Biochemistry, 80 Tennis Court Road, Cambridge CB2 1GA, United Kingdom
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50
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Izard T. A novel adenylate binding site confers phosphopantetheine adenylyltransferase interactions with coenzyme A. J Bacteriol 2003; 185:4074-80. [PMID: 12837781 PMCID: PMC164871 DOI: 10.1128/jb.185.14.4074-4080.2003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phosphopantetheine adenylyltransferase (PPAT) regulates the key penultimate step in the essential coenzyme A (CoA) biosynthetic pathway. PPAT catalyzes the reversible transfer of an adenylyl group from Mg(2+):ATP to 4'-phosphopantetheine to form 3'-dephospho-CoA (dPCoA) and pyrophosphate. The high-resolution crystal structure of PPAT complexed with CoA has been determined. Remarkably, CoA and the product dPCoA bind to the active site in distinct ways. Although the phosphate moiety within the phosphopantetheine arm overlaps, the pantetheine arm binds to the same pocket in two distinct conformations, and the adenylyl moieties of these two ligands have distinct binding sites. Moreover, the PPAT:CoA crystal structure confirms the asymmetry of binding to the two trimers within the hexameric enzyme. Specifically, the pantetheine arm of CoA bound to one protomer within the asymmetric unit displays the dPCoA-like conformation with the adenylyl moiety disordered, whereas CoA binds the twofold-related protomer in an ordered and unique fashion.
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Affiliation(s)
- Tina Izard
- Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA.
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