1
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Paneque A, Fortus H, Zheng J, Werlen G, Jacinto E. The Hexosamine Biosynthesis Pathway: Regulation and Function. Genes (Basel) 2023; 14:genes14040933. [PMID: 37107691 PMCID: PMC10138107 DOI: 10.3390/genes14040933] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/13/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
The hexosamine biosynthesis pathway (HBP) produces uridine diphosphate-N-acetyl glucosamine, UDP-GlcNAc, which is a key metabolite that is used for N- or O-linked glycosylation, a co- or post-translational modification, respectively, that modulates protein activity and expression. The production of hexosamines can occur via de novo or salvage mechanisms that are catalyzed by metabolic enzymes. Nutrients including glutamine, glucose, acetyl-CoA, and UTP are utilized by the HBP. Together with availability of these nutrients, signaling molecules that respond to environmental signals, such as mTOR, AMPK, and stress-regulated transcription factors, modulate the HBP. This review discusses the regulation of GFAT, the key enzyme of the de novo HBP, as well as other metabolic enzymes that catalyze the reactions to produce UDP-GlcNAc. We also examine the contribution of the salvage mechanisms in the HBP and how dietary supplementation of the salvage metabolites glucosamine and N-acetylglucosamine could reprogram metabolism and have therapeutic potential. We elaborate on how UDP-GlcNAc is utilized for N-glycosylation of membrane and secretory proteins and how the HBP is reprogrammed during nutrient fluctuations to maintain proteostasis. We also consider how O-GlcNAcylation is coupled to nutrient availability and how this modification modulates cell signaling. We summarize how deregulation of protein N-glycosylation and O-GlcNAcylation can lead to diseases including cancer, diabetes, immunodeficiencies, and congenital disorders of glycosylation. We review the current pharmacological strategies to inhibit GFAT and other enzymes involved in the HBP or glycosylation and how engineered prodrugs could have better therapeutic efficacy for the treatment of diseases related to HBP deregulation.
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Affiliation(s)
- Alysta Paneque
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Harvey Fortus
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Julia Zheng
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Guy Werlen
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Estela Jacinto
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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2
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Ruegenberg S, Mayr FAMC, Atanassov I, Baumann U, Denzel MS. Protein kinase A controls the hexosamine pathway by tuning the feedback inhibition of GFAT-1. Nat Commun 2021; 12:2176. [PMID: 33846315 PMCID: PMC8041777 DOI: 10.1038/s41467-021-22320-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 03/10/2021] [Indexed: 02/01/2023] Open
Abstract
The hexosamine pathway (HP) is a key anabolic pathway whose product uridine 5'-diphospho-N-acetyl-D-glucosamine (UDP-GlcNAc) is an essential precursor for glycosylation processes in mammals. It modulates the ER stress response and HP activation extends lifespan in Caenorhabditis elegans. The highly conserved glutamine fructose-6-phosphate amidotransferase 1 (GFAT-1) is the rate-limiting HP enzyme. GFAT-1 activity is modulated by UDP-GlcNAc feedback inhibition and via phosphorylation by protein kinase A (PKA). Molecular consequences of GFAT-1 phosphorylation, however, remain poorly understood. Here, we identify the GFAT-1 R203H substitution that elevates UDP-GlcNAc levels in C. elegans. In human GFAT-1, the R203H substitution interferes with UDP-GlcNAc inhibition and with PKA-mediated Ser205 phosphorylation. Our data indicate that phosphorylation affects the interactions of the two GFAT-1 domains to control catalytic activity. Notably, Ser205 phosphorylation has two discernible effects: it lowers baseline GFAT-1 activity and abolishes UDP-GlcNAc feedback inhibition. PKA controls the HP by uncoupling the metabolic feedback loop of GFAT-1.
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Affiliation(s)
- Sabine Ruegenberg
- grid.419502.b0000 0004 0373 6590Max Planck Institute for Biology of Ageing, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Institute of Biochemistry, University of Cologne, Cologne, Germany
| | - Felix A. M. C. Mayr
- grid.419502.b0000 0004 0373 6590Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Ilian Atanassov
- grid.419502.b0000 0004 0373 6590Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Ulrich Baumann
- grid.6190.e0000 0000 8580 3777Institute of Biochemistry, University of Cologne, Cologne, Germany
| | - Martin S. Denzel
- grid.419502.b0000 0004 0373 6590Max Planck Institute for Biology of Ageing, Cologne, Germany ,grid.6190.e0000 0000 8580 3777CECAD - Cluster of Excellence, University of Cologne, Cologne, Germany ,grid.6190.e0000 0000 8580 3777Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
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3
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Oliveira IA, Allonso D, Fernandes TVA, Lucena DMS, Ventura GT, Dias WB, Mohana-Borges RS, Pascutti PG, Todeschini AR. Enzymatic and structural properties of human glutamine:fructose-6-phosphate amidotransferase 2 (hGFAT2). J Biol Chem 2020; 296:100180. [PMID: 33303629 PMCID: PMC7948480 DOI: 10.1074/jbc.ra120.015189] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 11/24/2022] Open
Abstract
Glycoconjugates play a central role in several cellular processes, and alteration in their composition is associated with numerous human pathologies. Substrates for cellular glycosylation are synthesized in the hexosamine biosynthetic pathway, which is controlled by the glutamine:fructose-6-phosphate amidotransfera-se (GFAT). Human isoform 2 GFAT (hGFAT2) has been implicated in diabetes and cancer; however, there is no information about structural and enzymatic properties of this enzyme. Here, we report a successful expression and purification of a catalytically active recombinant hGFAT2 (rhGFAT2) in Escherichia coli cells fused or not to a HisTag at the C-terminal end. Our enzyme kinetics data suggest that hGFAT2 does not follow the expected ordered bi–bi mechanism, and performs the glucosamine-6-phosphate synthesis much more slowly than previously reported for other GFATs. In addition, hGFAT2 is able to isomerize fructose-6-phosphate into glucose-6-phosphate even in the presence of equimolar amounts of glutamine, which results in unproductive glutamine hydrolysis. Structural analysis of a three-dimensional model of rhGFAT2, corroborated by circular dichroism data, indicated the presence of a partially structured loop in the glutaminase domain, whose sequence is present in eukaryotic enzymes but absent in the E. coli homolog. Molecular dynamics simulations suggest that this loop is the most flexible portion of the protein and plays a key role on conformational states of hGFAT2. Thus, our study provides the first comprehensive set of data on the structure, kinetics, and mechanics of hGFAT2, which will certainly contribute to further studies on the (patho)physiology of hGFAT2.
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Affiliation(s)
- Isadora A Oliveira
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
| | - Diego Allonso
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil; Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, UFRJ, Rio de Janeiro, RJ, Brazil
| | - Tácio V A Fernandes
- Laboratório de Modelagem e Dinâmica Molecular, IBCCF, UFRJ, Rio de Janeiro, RJ, Brazil; Laboratório de Macromoléculas, Diretoria de Metrologia Aplicada às Ciências da Vida, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ, Brazil
| | - Daniela M S Lucena
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Gustavo T Ventura
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | - Wagner Barbosa Dias
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil
| | | | - Pedro G Pascutti
- Laboratório de Modelagem e Dinâmica Molecular, IBCCF, UFRJ, Rio de Janeiro, RJ, Brazil
| | - Adriane R Todeschini
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho (IBCCF), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ, Brazil.
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4
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Santos ARS, Gerhardt ECM, Moure VR, Pedrosa FO, Souza EM, Diamanti R, Högbom M, Huergo LF. Kinetics and structural features of dimeric glutamine-dependent bacterial NAD + synthetases suggest evolutionary adaptation to available metabolites. J Biol Chem 2018; 293:7397-7407. [PMID: 29581233 DOI: 10.1074/jbc.ra118.002241] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/11/2018] [Indexed: 01/09/2023] Open
Abstract
NADH (NAD+) and its reduced form NADH serve as cofactors for a variety of oxidoreductases that participate in many metabolic pathways. NAD+ also is used as substrate by ADP-ribosyl transferases and by sirtuins. NAD+ biosynthesis is one of the most fundamental biochemical pathways in nature, and the ubiquitous NAD+ synthetase (NadE) catalyzes the final step in this biosynthetic route. Two different classes of NadE have been described to date: dimeric single-domain ammonium-dependent NadENH3 and octameric glutamine-dependent NadEGln, and the presence of multiple NadE isoforms is relatively common in prokaryotes. Here, we identified a novel dimeric group of NadEGln in bacteria. Substrate preferences and structural analyses suggested that dimeric NadEGln enzymes may constitute evolutionary intermediates between dimeric NadENH3 and octameric NadEGln The characterization of additional NadE isoforms in the diazotrophic bacterium Azospirillum brasilense along with the determination of intracellular glutamine levels in response to an ammonium shock led us to propose a model in which these different NadE isoforms became active accordingly to the availability of nitrogen. These data may explain the selective pressures that support the coexistence of multiple isoforms of NadE in some prokaryotes.
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Affiliation(s)
| | | | | | | | | | - Riccardo Diamanti
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden
| | - Martin Högbom
- Department of Biochemistry and Biophysics, Stockholm University, 106 91 Stockholm, Sweden
| | - Luciano Fernandes Huergo
- Department of Biochemistry and Molecular Biology, Curitiba, PR, 512 Brazil; Setor Litoral, Universidade Federal do Paraná (UFPR), Curitiba, PR, 512 Brazil.
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5
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Wei W, Monard G, Gauld J. Computational insights into substrate binding and catalytic mechanism of the glutaminase domain of glucosamine-6-phosphate synthase (GlmS). RSC Adv 2017. [DOI: 10.1039/c7ra04906d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The mechanistic cysteinyl of GlmS can activate its thiol using its own α-amine without the need for a bridging water.
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Affiliation(s)
- Wanlei Wei
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
| | - Gerald Monard
- Université de Lorraine
- UMR 7565 SRSMC
- F-54506 Vandoeuvre-les-Nancy
- France
| | - James W. Gauld
- Department of Chemistry and Biochemistry
- University of Windsor
- Windsor
- Canada
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6
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Marques SM, Daniel L, Buryska T, Prokop Z, Brezovsky J, Damborsky J. Enzyme Tunnels and Gates As Relevant Targets in Drug Design. Med Res Rev 2016; 37:1095-1139. [PMID: 27957758 DOI: 10.1002/med.21430] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/11/2016] [Accepted: 11/07/2016] [Indexed: 12/28/2022]
Abstract
Many enzymes contain tunnels and gates that are essential to their function. Gates reversibly switch between open and closed conformations and thereby control the traffic of small molecules-substrates, products, ions, and solvent molecules-into and out of the enzyme's structure via molecular tunnels. Many transient tunnels and gates undoubtedly remain to be identified, and their functional roles and utility as potential drug targets have received comparatively little attention. Here, we describe a set of general concepts relating to the structural properties, function, and classification of these interesting structural features. In addition, we highlight the potential of enzyme tunnels and gates as targets for the binding of small molecules. The different types of binding that are possible and the potential pharmacological benefits of such targeting are discussed. Twelve examples of ligands bound to the tunnels and/or gates of clinically relevant enzymes are used to illustrate the different binding modes and to explain some new strategies for drug design. Such strategies could potentially help to overcome some of the problems facing medicinal chemists and lead to the discovery of more effective drugs.
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Affiliation(s)
- Sergio M Marques
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Lukas Daniel
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Tomas Buryska
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Zbynek Prokop
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Jan Brezovsky
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories, Faculty of Science, Department of Experimental Biology and Research Centre for Toxic Compounds in the Environment, RECETOX, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.,International Centre for Clinical Research, St. Anne's University Hospital, Pekarska 53, 656 91, Brno, Czech Republic
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7
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Tan XE, Neoh HM, Looi ML, Chin SF, Cui L, Hiramatsu K, Hussin S, Jamal R. Activated ADI pathway: the initiator of intermediate vancomycin resistance in Staphylococcus aureus. Can J Microbiol 2016; 63:260-264. [PMID: 28059579 DOI: 10.1139/cjm-2016-0439] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Comparative proteomic profiling between 2 vancomycin-intermediate Staphylococcus aureus (VISA) strains, Mu50Ω-vraSm and Mu50Ω-vraSm-graRm, and vancomycin-susceptible S. aureus (VSSA) strain Mu50Ω revealed upregulated levels of catabolic ornithine carbamoyltransferase (ArcB) of the arginine catabolism pathway in VISA strains. Subsequent analyses showed that the VISA strains have higher levels of cellular ATP and ammonia, which are by-products of arginine catabolism, and displayed thicker cell walls. We postulate that elevated cytoplasmic ammonia and ATP molecules, resulting from activated arginine catabolism upon acquisition of vraS and graR mutations, are important requirements facilitating cell wall biosynthesis, thereby contributing to thickened cell wall and consequently reduced vancomycin susceptibility in VISA strains.
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Affiliation(s)
- Xin-Ee Tan
- a UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
| | - Hui-Min Neoh
- a UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia.,b Department of Bacteriology, School of Medicine, Juntendo University, Japan
| | - Mee-Lee Looi
- a UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia.,c Taylor's University Lakeside Campus, School of Biosciences, Malaysia
| | - Siok Fong Chin
- a UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
| | - Longzhu Cui
- d Division of Bacteriology, Department of Infection and Immunity, School of Medicine, Jichi Medical University, Japan
| | - Keiichi Hiramatsu
- b Department of Bacteriology, School of Medicine, Juntendo University, Japan
| | - Salasawati Hussin
- e Department of Medical Microbiology and Immunology, Universiti Kebangsaan Malaysia, Malaysia
| | - Rahman Jamal
- a UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
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8
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Yang L, Zhang J, Che X, Gao YQ. Simulation Studies of Protein and Small Molecule Interactions and Reaction. Methods Enzymol 2016; 578:169-212. [PMID: 27497167 DOI: 10.1016/bs.mie.2016.05.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Computational studies of protein and small molecule (protein-ligand/enzyme-substrate) interactions become more and more important in biological science and drug discovery. Computer modeling can provide molecular details of the processes such as conformational change, binding, and transportation of small molecules/proteins, which are not easily to be captured in experiments. In this chapter, we discussed simulation studies of both protein and small molecules from three aspects: conformation sampling, transportations of small molecules in enzymes, and enzymatic reactions involving small molecules. Both methodology developments and examples of simulation studies in this field were presented.
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Affiliation(s)
- L Yang
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, PR China; Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, PR China
| | - J Zhang
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, PR China; Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, PR China
| | - X Che
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, PR China; Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, PR China
| | - Y Q Gao
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, PR China; Biodynamic Optical Imaging Center (BIOPIC), Peking University, Beijing, PR China.
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9
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Isolation of the GFA1 gene encoding glucosamine-6-phosphate synthase of Sporothrix schenckii and its expression in Saccharomyces cerevisiae. Protein Expr Purif 2015; 110:57-64. [DOI: 10.1016/j.pep.2014.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/01/2014] [Accepted: 12/03/2014] [Indexed: 02/04/2023]
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10
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Affiliation(s)
- Artur Gora
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
| | - Jan Brezovsky
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
- International Centre for Clinical
Research, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
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11
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Jorda J, Lopez D, Wheatley NM, Yeates TO. Using comparative genomics to uncover new kinds of protein-based metabolic organelles in bacteria. Protein Sci 2013. [PMID: 23188745 DOI: 10.1002/pro.2196] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bacterial microcompartment (MCP) organelles are cytosolic, polyhedral structures consisting of a thin protein shell and a series of encapsulated, sequentially acting enzymes. To date, different microcompartments carrying out three distinct types of metabolic processes have been characterized experimentally in various bacteria. In the present work, we use comparative genomics to explore the existence of yet uncharacterized microcompartments encapsulating a broader set of metabolic pathways. A clustering approach was used to group together enzymes that show a strong tendency to be encoded in chromosomal proximity to each other while also being near genes for microcompartment shell proteins. The results uncover new types of putative microcompartments, including one that appears to encapsulate B(12) -independent, glycyl radical-based degradation of 1,2-propanediol, and another potentially involved in amino alcohol metabolism in mycobacteria. Preliminary experiments show that an unusual shell protein encoded within the glycyl radical-based microcompartment binds an iron-sulfur cluster, hinting at complex mechanisms in this uncharacterized system. In addition, an examination of the computed microcompartment clusters suggests the existence of specific functional variations within certain types of MCPs, including the alpha carboxysome and the glycyl radical-based microcompartment. The findings lead to a deeper understanding of bacterial microcompartments and the pathways they sequester.
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Affiliation(s)
- Julien Jorda
- UCLA-DOE Institute for Genomics and Proteomics, 611 Charles Young Dr East, Los Angeles, California 90095, USA
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12
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Mouilleron S, Badet-Denisot MA, Pecqueur L, Madiona K, Assrir N, Badet B, Golinelli-Pimpaneau B. Structural basis for morpheein-type allosteric regulation of Escherichia coli glucosamine-6-phosphate synthase: equilibrium between inactive hexamer and active dimer. J Biol Chem 2012; 287:34533-46. [PMID: 22851174 DOI: 10.1074/jbc.m112.380378] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The amino-terminal cysteine of glucosamine-6-phosphate synthase (GlmS) acts as a nucleophile to release and transfer ammonia from glutamine to fructose 6-phosphate through a channel. The crystal structure of the C1A mutant of Escherichia coli GlmS, solved at 2.5 Å resolution, is organized as a hexamer, where the glutaminase domains adopt an inactive conformation. Although the wild-type enzyme is active as a dimer, size exclusion chromatography, dynamic and quasi-elastic light scattering, native polyacrylamide gel electrophoresis, and ultracentrifugation data show that the dimer is in equilibrium with a hexameric state, in vitro and in cellulo. The previously determined structures of the wild-type enzyme, alone or in complex with glucosamine 6-phosphate, are also consistent with a hexameric assembly that is catalytically inactive because the ammonia channel is not formed. The shift of the equilibrium toward the hexameric form in the presence of cyclic glucosamine 6-phosphate, together with the decrease of the specific activity with increasing enzyme concentration, strongly supports product inhibition through hexamer stabilization. Altogether, our data allow us to propose a morpheein model, in which the active dimer can rearrange into a transiently stable form, which has the propensity to form an inactive hexamer. This would account for a physiologically relevant allosteric regulation of E. coli GlmS. Finally, in addition to cyclic glucose 6-phosphate bound at the active site, the hexameric organization of E. coli GlmS enables the binding of another linear sugar molecule. Targeting this sugar-binding site to stabilize the inactive hexameric state is therefore suggested for the development of specific antibacterial inhibitors.
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Affiliation(s)
- Stéphane Mouilleron
- Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
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13
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Regulation of the intersubunit ammonia tunnel in Mycobacterium tuberculosis glutamine-dependent NAD+ synthetase. Biochem J 2012; 443:417-26. [PMID: 22280445 DOI: 10.1042/bj20112210] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Glutamine-dependent NAD+ synthetase is an essential enzyme and a validated drug target in Mycobacterium tuberculosis (mtuNadE). It catalyses the ATP-dependent formation of NAD+ from NaAD+ (nicotinic acid-adenine dinucleotide) at the synthetase active site and glutamine hydrolysis at the glutaminase active site. An ammonia tunnel 40 Å (1 Å=0.1 nm) long allows transfer of ammonia from one active site to the other. The enzyme displays stringent kinetic synergism; however, its regulatory mechanism is unclear. In the present paper, we report the structures of the inactive glutaminase C176A variant in an apo form and in three synthetase-ligand complexes with substrates (NaAD+/ATP), substrate analogue {NaAD+/AMP-CPP (adenosine 5'-[α,β-methylene]triphosphate)} and intermediate analogues (NaAD+/AMP/PPi), as well as the structure of wild-type mtuNadE in a product complex (NAD+/AMP/PPi/glutamate). This series of structures provides snapshots of the ammonia tunnel during the catalytic cycle supported also by kinetics and mutagenesis studies. Three major constriction sites are observed in the tunnel: (i) at the entrance near the glutaminase active site; (ii) in the middle of the tunnel; and (iii) at the end near the synthetase active site. Variation in the number and radius of the tunnel constrictions is apparent in the crystal structures and is related to ligand binding at the synthetase domain. These results provide new insight into the regulation of ammonia transport in the intermolecular tunnel of mtuNadE.
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14
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Kang J, Kuroyanagi S, Akisada T, Hagiwara Y, Tateno M. Unidirectional Mechanistic Valved Mechanisms for Ammonia Transport in GatCAB. J Chem Theory Comput 2012; 8:649-60. [PMID: 26596613 DOI: 10.1021/ct200387u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glutamine amidotransferase CAB (GatCAB), a crucial enzyme involved in translational fidelity, catalyzes three reactions: (i) the glutaminase reaction to yield ammonia (NH3 or NH4(+)) from glutamine, (ii) the phosphorylation of Glu-tRNA(Gln), and (iii) the transamidase reaction to convert the phosphorylated Glu-tRNA(Gln) to Gln-tRNA(Gln). In the crystal structure of GatCAB, the two catalytic centers are far apart, and the presence of a hydrophilic channel to transport the molecules produced by the reaction (i) was proposed. We investigated the transport mechanisms of GatCAB by molecular dynamics (MD) simulations and free energy (PMF) calculations. In the MD simulations (in total ∼1.1 μs), the entrance of the previously proposed channel is closed, as observed in the crystal structure. Instead, a novel hydrophobic channel has been identified in this study: Since the newly identified entrance opened and closed repeatedly in the MD simulations, it may act as a gate. The calculated free energy difference revealed the significant preference of the newly identified gate/channel for NH3 transport (∼10(4)-fold). In contrast, with respect to NH4(+), the free energy barriers are significantly increased for both channels due to tight hydrogen-bonding with hydrophilic residues, which hinders efficient transport. The opening of the newly identified gate is modulated by Phe206, which acts as a "valve". For the backward flow of NH3, our PMF calculation revealed that the opening of the gate is hindered by Ala207, which acts as a mechanistic "stopper" against the motion of the "valve" (Phe206). This is the first report to elucidate the detailed mechanisms of unidirectional mechanistic valved transport inside proteins.
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Affiliation(s)
- Jiyoung Kang
- Graduate School of Pure and Applied Sciences, University of Tsukuba , Tennodai 1-1-1, Tsukuba Science City, Ibaraki 305-8571, Japan
| | - Shigehide Kuroyanagi
- Graduate School of Pure and Applied Sciences, University of Tsukuba , Tennodai 1-1-1, Tsukuba Science City, Ibaraki 305-8571, Japan
| | - Tomohiro Akisada
- Graduate School of Life Science, University of Hyogo , 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Yohsuke Hagiwara
- Graduate School of Pure and Applied Sciences, University of Tsukuba , Tennodai 1-1-1, Tsukuba Science City, Ibaraki 305-8571, Japan
| | - Masaru Tateno
- Graduate School of Life Science, University of Hyogo , 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
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López-Romero E, Reyes-Montes MDR, Pérez-Torres A, Ruiz-Baca E, Villagómez-Castro JC, Mora-Montes HM, Flores-Carreón A, Toriello C. Sporothrix schenckii complex and sporotrichosis, an emerging health problem. Future Microbiol 2011; 6:85-102. [DOI: 10.2217/fmb.10.157] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Sporothrix schenckii, now named the S. schenckii species complex, has largely been known as the etiological agent of sporotrichosis, which is an acute or chronic subcutaneous mycosis of humans and other mammals. Gene sequencing has revealed the following species in the S. schenckii complex: Sporothrix albicans, Sporothrix brasiliensis, Sporothrix globosa, Sporothrix luriei, Sporothrix mexicana and S. schenckii. The increasing number of reports of Sporothrix infection in immunocompromised patients, mainly the HIV-infected population, suggests sporotrichosis as an emerging global health problem concomitant with the AIDS pandemic. Molecular studies have demonstrated a high level of intraspecific variability. Components of the S. schenckii cell wall that act as adhesins and immunogenic inducers, such as a 70-kDa glycoprotein, are apparently specific to this fungus. The main glycan peptidorhamnomannan cell wall component is the only O-linked glycan structure known in S. schenckii. It contains an α-mannobiose core followed by one α-glucuronic acid unit, which may be mono- or di-rhamnosylated. The oligomeric structure of glucosamine-6-P synthase has led to a significant advance in the development of antifungals targeted to the enzyme’s catalytic domain in S. schenckii.
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16
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Mouilleron S, Badet-Denisot MA, Badet B, Golinelli-Pimpaneau B. Dynamics of glucosamine-6-phosphate synthase catalysis. Arch Biochem Biophys 2010; 505:1-12. [PMID: 20709015 DOI: 10.1016/j.abb.2010.08.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 08/06/2010] [Accepted: 08/08/2010] [Indexed: 11/19/2022]
Abstract
Glucosamine-6P synthase, which catalyzes glucosamine-6P synthesis from fructose-6P and glutamine, channels ammonia over 18Å between its glutaminase and synthase active sites. The crystal structures of the full-length Escherichia coli enzyme have been determined alone, in complex with the first bound substrate, fructose-6P, in the presence of fructose-6P and a glutamine analog, and in the presence of the glucosamine-6P product. These structures represent snapshots of reaction intermediates, and their comparison sheds light on the dynamics of catalysis. Upon fructose-6P binding, the C-terminal loop and the glutaminase domains get ordered, leading to the closure of the synthase site, the opening of the sugar ring and the formation of a "closed" ammonia channel. Then, glutamine binding leads to the closure of the Q-loop to protect the glutaminase site, the activation of the catalytic residues involved in glutamine hydrolysis, the swing of the side chain of Trp74, which allows the communication between the two active sites through an "open" channel, and the rotation of the glutaminase domains relative to the synthase domains dimer. Therefore, binding of the substrates at the appropriate reaction time is responsible for the formation and opening of the ammonia channel and for the activation of the enzyme glutaminase function.
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Affiliation(s)
- Stéphane Mouilleron
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 1 avenue de la Terrasse, 91198 Gif-sur-Yvette, France.
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17
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Lund L, Fan Y, Shao Q, Gao YQ, Raushel FM. Carbamate transport in carbamoyl phosphate synthetase: a theoretical and experimental investigation. J Am Chem Soc 2010; 132:3870-8. [PMID: 20187643 DOI: 10.1021/ja910441v] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transport of carbamate through the large subunit of carbamoyl phosphate synthetase (CPS) from Escherichia coli was investigated by molecular dynamics and site-directed mutagenesis. Carbamate, the product of the reaction involving ATP, bicarbonate, and ammonia, must be delivered from the site of formation to the site of utilization by traveling nearly 40 A within the enzyme. Potentials of mean force (PMF) calculations along the entire tunnel for the translocation of carbamate indicate that the tunnel is composed of three continuous water pockets and two narrow connecting parts, near Ala-23 and Gly-575. The two narrow parts render two free energy barriers of 6.7 and 8.4 kcal/mol, respectively. Three water pockets were filled with about 21, 9, and 9 waters, respectively, and the corresponding relative free energies of carbamate residing in these free energy minima are 5.8, 0, and 1.6 kcal/mol, respectively. The release of phosphate into solution at the site for the formation of carbamate allows the side chain of Arg-306 to rotate toward Glu-25, Glu-383, and Glu-604. This rotation is virtually prohibited by a barrier of at least 23 kcal/mol when phosphate remains bound. This conformational change not only opens the entrance of the tunnel but also shields the charge-charge repulsion from the three glutamate residues when carbamate passes through the tunnel. Two mutants, A23F and G575F, were designed to block the migration of carbamate through the narrowest parts of the carbamate tunnel. The mutants retained only 1.7% and 3.8% of the catalytic activity for the synthesis of carbamoyl phosphate relative to the wild type CPS, respectively.
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Affiliation(s)
- Liliya Lund
- Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, USA
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18
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Valerio-Lepiniec M, Aumont-Nicaise M, Roux C, Raynal B, England P, Badet B, Badet-Denisot MA, Desmadril M. Analysis of the Escherichia coli glucosamine-6-phosphate synthase activity by isothermal titration calorimetry and differential scanning calorimetry. Arch Biochem Biophys 2010; 498:95-104. [PMID: 20416269 DOI: 10.1016/j.abb.2010.04.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 04/14/2010] [Accepted: 04/14/2010] [Indexed: 11/25/2022]
Abstract
Glucosamine-6-phosphate synthase (GlmS) is responsible for the first and rate-limiting step in the hexosamine biosynthetic pathway. It catalyzes the conversion of D-fructose-6P (F6P) into D-glucosamine-6P (GlcN6P) using L-glutamine (Gln) as nitrogen donor (synthase activity) according to an ordered bi-bi process where F6P binds first. In the absence of F6P, the enzyme exhibits a weak hydrolyzing activity of Gln into Glu and ammonia (glutaminase activity), whereas the presence of F6P strongly stimulates it (hemi-synthase activity). Until now, these different activities were indirectly measured using either coupled enzyme or colorimetric methods. In this work, we have developed a direct assay monitoring the heat released by the reaction. Isothermal titration calorimetry and differential scanning calorimetry were used to determine kinetic and thermodynamic parameters of GlmS. The direct determination at 37 degrees C of kinetic parameters and affinity constants for both F6P and Gln demonstrated that part of the ammonia produced by Gln hydrolysis in the presence of both substrates is not used for the formation of the GlcN6P. The full characterization of this phenomenon allowed to identify experimental conditions where this leak of ammonia is negligible. Enthalpy measurements at 25 degrees C in buffers of various heats of protonation demonstrated that no proton exchange with the medium occurred during the enzyme-catalyzed glutaminase or synthase reaction suggesting for the first time that both products are released as a globally neutral pair composed by the Glu carboxylic side chain and the GlcN6P amine function. Finally we showed that the oligomerization state of GlmS is concentration-dependent.
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Affiliation(s)
- Marie Valerio-Lepiniec
- Institut de Biochimie et Biophysique Moléculaire et Cellulaire, UMR 8619, Université de Paris-Sud 11, Orsay, France.
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19
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Wang XS, Roitberg AE, Richards NGJ. Computational Studies of Ammonia Channel Function in Glutamine 5′-Phosphoribosylpyrophosphate Amidotransferase. Biochemistry 2009; 48:12272-82. [DOI: 10.1021/bi901521d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiang S. Wang
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435
| | - Adrian E. Roitberg
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435
| | - Nigel G. J. Richards
- Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, and Quantum Theory Project, University of Florida, Gainesville, Florida 32611-8435
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20
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Fan Y, Lund L, Shao Q, Gao YQ, Raushel FM. A combined theoretical and experimental study of the ammonia tunnel in carbamoyl phosphate synthetase. J Am Chem Soc 2009; 131:10211-9. [PMID: 19569682 DOI: 10.1021/ja902557r] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transfer of ammonia in carbamoyl phosphate synthetase (CPS) was investigated by molecular dynamics simulations and experimental characterization of mutations within the ammonia tunnel. In CPS, ammonia is derived from the hydrolysis of glutamine and this intermediate must travel approximately 45 A from the site of formation in the small subunit to the site of utilization in the large subunit. In this investigation, the migration of ammonia was analyzed from the exit of the small subunit through the large subunit where it ultimately reacts with the carboxy phosphate intermediate. Potential of mean force calculations along the transfer pathway for ammonia indicate a relatively low free-energy barrier for the translocation of ammonia. The highest barrier of 7.2 kcal/mol is found at a narrow turning gate surrounded by the side chains of Cys-232, Ala-251, and Ala-314 in the large subunit. The environment of the ammonia tunnel from the exit of the small subunit to the turning gate in the tunnel is filled with clusters of water molecules and the ammonia is able to travel through this area easily. After ammonia passes through the turning gate, it enters a hydrophobic passage. A hydrogen bond then forms between the ammonia and Thr-249, which facilitates the delivery to a more hydrophilic environment near the active site for the reaction with the carboxy phosphate intermediate. The transport process from the turning gate to the end of the tunnel is favored by an overall downhill free-energy potential and no free-energy barrier higher than 3 kcal/mol. A conformational change of the turning gate, caused by formation of the carboxy phosphate intermediate, is consistent with a mechanism in which the reaction between ATP and bicarbonate triggers the transport of ammonia and consequently accelerates the rate of glutamine hydrolysis in the small subunit. A blockage in the turning gate passageway was introduced by the triple mutant C232V/A251V/A314V. This mutant is unable to synthesize carbamoyl phosphate using glutamine as a nitrogen source.
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Affiliation(s)
- Yubo Fan
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
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Floquet N, Durand P, Maigret B, Badet B, Badet-Denisot MA, Perahia D. Collective motions in glucosamine-6-phosphate synthase: influence of ligand binding and role in ammonia channelling and opening of the fructose-6-phosphate binding site. J Mol Biol 2008; 385:653-64. [PMID: 18976669 DOI: 10.1016/j.jmb.2008.10.032] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 09/24/2008] [Accepted: 10/09/2008] [Indexed: 11/28/2022]
Abstract
The large protein motions of the bacterial enzyme glucosamine-6-phosphate synthase have been addressed using full atom normal modes analysis for the empty, the glucose-6-phosphate and the glucose-6-phosphate+glutamate bound proteins. The approach that was used involving energy minimizations along the normal modes coordinates identified functional motions of the protein, some of which were characterized earlier by X-ray diffraction studies. This method made it possible for the first time to highlight significant energy differences according to whether none, only one or both of the active sites of the protein were occupied. Our data favoured a specific motion of the glutamine binding domain following the fixation of fructose-6-phosphate and suggested a rigidified structure with both sites occupied. Here, we show that most of the collective large amplitude motions of glucosamine-6-phosphate synthase that are modulated by ligand binding are crucial for the enzyme catalytic cycle, as they strongly modify the geometry of both the ammonia channel and the C-tail, demonstrating their role in ammonia transfer and ligand binding.
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Affiliation(s)
- Nicolas Floquet
- Institut de Chimie des Substances Naturelles-CNRS, 1 Avenue de la Terrasse-91198 Gif-sur-Yvette, France
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22
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Diffusional channeling in the sulfate-activating complex: combined continuum modeling and coarse-grained brownian dynamics studies. Biophys J 2008; 95:4659-67. [PMID: 18689458 PMCID: PMC2576392 DOI: 10.1529/biophysj.108.140038] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enzymes required for sulfur metabolism have been suggested to gain efficiency by restricted diffusion (i.e., channeling) of an intermediate APS(2-) between active sites. This article describes modeling of the whole channeling process by numerical solution of the Smoluchowski diffusion equation, as well as by coarse-grained Brownian dynamics. The results suggest that electrostatics plays an essential role in the APS(2-) channeling. Furthermore, with coarse-grained Brownian dynamics, the substrate channeling process has been studied with reactions in multiple active sites. Our simulations provide a bridge for numerical modeling with Brownian dynamics to simulate the complicated reaction and diffusion and raise important questions relating to the electrostatically mediated substrate channeling in vitro, in situ, and in vivo.
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23
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Vanoni MA, Curti B. Structure-function studies of glutamate synthases: a class of self-regulated iron-sulfur flavoenzymes essential for nitrogen assimilation. IUBMB Life 2008; 60:287-300. [PMID: 18421771 DOI: 10.1002/iub.52] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glutamate synthases play with glutamine synthetase an essential role in nitrogen assimilation processes in microorganisms, plants, and lower animals by catalyzing the net synthesis of one molecule of L-glutamate from L-glutamine and 2-oxoglutarate. They exhibit a modular architecture with a common subunit or region, which is responsible for the L-glutamine-dependent glutamate synthesis from 2-oxoglutarate. Here, a PurF- (Type II- or Ntn-) type amidotransferase domain is coupled to the synthase domain, a (beta/alpha)8 barrel containing FMN and one [3Fe-4S]0,+1 cluster, through a approximately 30 angstroms-long intramolecular tunnel for the transfer of ammonia between the sites. In bacterial and eukaryotic GltS, reducing equivalents are provided by reduced pyridine nucleotides thanks to the stable association with a second subunit or region, which acts as a FAD-dependent NAD(P)H oxidoreductase and is responsible for the formation of the two low potential [4Fe-4S]+1,+2 clusters of the enzyme. In photosynthetic cells, reduced ferredoxin is the physiological reductant. This review focus on the mechanism of cross-activation of the synthase and glutaminase reactions in response to the bound substrates and the redox state of the enzyme cofactors, as well as on recent information on the structure of the alphabeta protomer of the NADPH-dependent enzyme, which sheds light on the intramolecular electron transfer pathway between the flavin cofactors.
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Affiliation(s)
- Maria Antonietta Vanoni
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Via Celoria 26, Milano, Italy.
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Mouilleron S, Badet-Denisot MA, Golinelli-Pimpaneau B. Ordering of C-terminal Loop and Glutaminase Domains of Glucosamine-6-Phosphate Synthase Promotes Sugar Ring Opening and Formation of the Ammonia Channel. J Mol Biol 2008; 377:1174-85. [DOI: 10.1016/j.jmb.2008.01.077] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 01/21/2008] [Accepted: 01/23/2008] [Indexed: 10/22/2022]
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25
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Barreteau H, Kovac A, Boniface A, Sova M, Gobec S, Blanot D. Cytoplasmic steps of peptidoglycan biosynthesis. FEMS Microbiol Rev 2008; 32:168-207. [PMID: 18266853 DOI: 10.1111/j.1574-6976.2008.00104.x] [Citation(s) in RCA: 479] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The biosynthesis of bacterial cell wall peptidoglycan is a complex process that involves enzyme reactions that take place in the cytoplasm (synthesis of the nucleotide precursors) and on the inner side (synthesis of lipid-linked intermediates) and outer side (polymerization reactions) of the cytoplasmic membrane. This review deals with the cytoplasmic steps of peptidoglycan biosynthesis, which can be divided into four sets of reactions that lead to the syntheses of (1) UDP-N-acetylglucosamine from fructose 6-phosphate, (2) UDP-N-acetylmuramic acid from UDP-N-acetylglucosamine, (3) UDP-N-acetylmuramyl-pentapeptide from UDP-N-acetylmuramic acid and (4) D-glutamic acid and dipeptide D-alanyl-D-alanine. Recent data concerning the different enzymes involved are presented. Moreover, special attention is given to (1) the chemical and enzymatic synthesis of the nucleotide precursor substrates that are not commercially available and (2) the search for specific inhibitors that could act as antibacterial compounds.
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Affiliation(s)
- Hélène Barreteau
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Univ Paris-Sud, Orsay, France
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26
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Durand P, Golinelli-Pimpaneau B, Mouilleron S, Badet B, Badet-Denisot MA. Highlights of glucosamine-6P synthase catalysis. Arch Biochem Biophys 2008; 474:302-17. [PMID: 18279655 DOI: 10.1016/j.abb.2008.01.026] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 01/30/2008] [Accepted: 01/31/2008] [Indexed: 10/22/2022]
Abstract
L-Glutamine:d-fructose-6-phosphate amidotransferase, also known as glucosamine-6-phosphate synthase (GlcN6P synthase), which catalyzes the first step in a pathway leading to the formation of uridine 5'-diphospho-N-acetyl-d-glucosamine (UDP-GlcNAc), is a key point in the metabolic control of the biosynthesis of amino sugar-containing macromolecules. The molecular mechanism of the reaction catalyzed by GlcN6P synthase is complex and involves amide bond cleavage followed by ammonia channeling and sugar isomerization. This article provides a comprehensive overview of the present knowledge on this multi-faceted enzyme emphasizing the progress made during the last five years.
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Affiliation(s)
- Philippe Durand
- Institut de Chimie des Substances Naturelles-CNRS, 1 Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
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