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Jhangiani A, Panda V, Sukheja A, Thomas S, Dusseja P, Pandya S, Chintakrindi A. Toxicological Profiling of Potential Shikimate Kinase Inhibitors Against Mycobacterium tuberculosis. Altern Lab Anim 2024; 52:10-27. [PMID: 38095084 DOI: 10.1177/02611929231217062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Over the last decade, Mycobacterium tuberculosis has mutated into a putative 'superbug', as treatments against it have failed due to increasing antimicrobial resistance. As a result, the rising incidence of multidrug-resistant tuberculosis (MDR-TB) is posing a significant public health threat, thus, the need to develop effective drugs for MDR-TB has become an urgent priority. To identify new drug candidates for the treatment of MDR-TB, the present study was based on mycobacterial shikimate kinase (MtSK) as the pharmacological target. One hundred potential MtSK inhibitors were identified from literature and database searches to identify compounds that were designed to specifically function as MtSK antagonists. The ADME properties of these compounds were evaluated by using the SwissADME web tool. ProTox-II software was also used to investigate any potential endocrine disrupting effects, mediated through their interaction with oestrogenic and/or androgenic receptors. This study also aimed to predict LD50 values of potential drug candidates that would be active against the standard H37Rv strain of M. tuberculosis, by using the ProTox-II in silico tool. The molecules for which no structural hazard alerts were identified with these software tools were further subjected to molecular docking analyses and molecular dynamic simulations to estimate their ability to interact with the MtSK enzyme. Preliminary results from SwissADME indicated that 30 molecules were drug-like, due to their physicochemical and pharmacokinetic properties. However, subsequent analysis with ToxTree and ProTox-II indicated that only three of these 30 drug-like molecules were suitable for taking forward into further in vitro experiments. This study, which is based on the use of commonly used open-source in silico tools, identified new MtSK ligands for potential use in the development of new drugs for the therapeutic management of tuberculosis. An initial prediction of their safety profile was also generated.
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Affiliation(s)
| | - Vandana Panda
- Principal K.M. Kundnani College of Pharmacy, Mumbai, India
| | | | - Sneha Thomas
- Principal K.M. Kundnani College of Pharmacy, Mumbai, India
| | - Piyush Dusseja
- Principal K.M. Kundnani College of Pharmacy, Mumbai, India
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Bo T, Wu C, Wang Z, Jiang H, Wang F, Chen N, Li Y. Multiple Metabolic Engineering Strategies to Improve Shikimate Titer in Escherichia coli. Metabolites 2023; 13:747. [PMID: 37367905 DOI: 10.3390/metabo13060747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 06/08/2023] [Accepted: 06/09/2023] [Indexed: 06/28/2023] Open
Abstract
Shikimate is a valuable chiral precursor for synthesizing oseltamivir (Tamiflu®) and other chemicals. High production of shikimate via microbial fermentation has attracted increasing attention to overcome the unstable and expensive supply of shikimate extracted from plant resources. The current cost of microbial production of shikimate via engineered strains is still unsatisfactory, and thus more metabolic strategies need to be investigated to further increase the production efficiency. In this study, we first constructed a shikimate E. coli producer through the application of the non-phosphoenolpyruvate: carbohydrate phosphotransferase system (non-PTS) glucose uptake pathway, the attenuation of the shikimate degradation metabolism, and the introduction of a mutant of feedback-resistant 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase. Inspired by the natural presence of bifunctional 3-dehydroquinate dehydratase (DHD)-shikimate dehydrogenase (SDH) enzyme in plants, we then designed an artificial fusion protein of DHD-SDH to decrease the accumulation of the byproduct 3-dehydroshikimate (DHS). Subsequently, a repressed shikimate kinase (SK) mutant was selected to promote shikimate accumulation without the supplementation of expensive aromatic substances. Furthermore, EsaR-based quorum sensing (QS) circuits were employed to regulate the metabolic flux distribution between cell growth and product synthesis. The final engineered strain dSA10 produced 60.31 g/L shikimate with a yield of 0.30 g/g glucose in a 5 L bioreactor.
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Affiliation(s)
- Taidong Bo
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Chen Wu
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Zeting Wang
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Hao Jiang
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Feiao Wang
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ning Chen
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
- National and Local United Engineering Lab of Metabolic Control Fermentation Technology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yanjun Li
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China
- National and Local United Engineering Lab of Metabolic Control Fermentation Technology, Tianjin University of Science and Technology, Tianjin 300457, China
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Rajput VS, Runthala A, Khan IA. Shikimate kinase inhibitors: An update on promising strategy against Mycobacterium tuberculosis. Curr Drug Targets 2023:CDT-EPUB-129363. [PMID: 36752299 DOI: 10.2174/1389450124666230208102645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/16/2022] [Accepted: 11/25/2022] [Indexed: 02/09/2023]
Abstract
Humanity has been battling with tuberculosis (TB) for a long period, and despite the availability of drugs well-known to act against the deadly microbe, the menace is still very far from reaching its end. Moreover, problems related to TB chemotherapy, such as lengthy treatment periods leading to poor patient compliance, increasing drug resistance, and association with another deadlier disease HIV-AIDS, make the situation alarming, thereby pressing the need for the discovery of new potent drugs urgently. Therefore, a drug target that is essential for survival and exclusive to M. tuberculosis presents a promising platform to explore novel molecules against the microorganism for better pathogen clearance with minimal toxicity. The shikimate pathway that leads to the synthesis of essential aromatic amino acids is one such attractive target. Shikimate kinase, the fifth enzyme of this pathway, converts shikimate to shikimate-3-phosphate by using ATP as a co-substrate. Targeting shikimate kinase could be an effective strategy in light of its essentiality and absence of any homologue in mammals. This review discusses different strategies adopted for discovering novel compounds or scaffolds targeting M. tuberculosis shikimate kinase (MtSK) in vitro. The application of substrate analogues, their structure, and ligand-based approach for screening a library of anti-mycobacterial compounds, marine-derived molecules, and commercially available libraries have yielded promising MtSK inhibitors exhibiting micro-molar activities. To develop these leads into future drugs with minimum off-target effects on the host microenvironment, the molecules need to be structurally optimized for improved activities against enzymes and whole-cell organisms.
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Affiliation(s)
- Vikrant Singh Rajput
- Department of Biomedical Engineering, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, 305817, Ajmer, Rajasthan, India
| | - Ashish Runthala
- Department of Bio-Technology, Koneru Lakshmaiah Education Foundation, Vaddeswaram, AP, India
| | - Inshad Ali Khan
- Dept. of Microbiology, Central University of Rajasthan, NH-8, Bandarsindri, Kishangarh, 305817, Ajmer, Rajasthan, India
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Rios-Soto L, Téllez-Valencia A, Sierra-Campos E, Valdez-Solana M, Cisneros-Martínez J, Gómez Palacio-Gastélum M, Castillo-Villanueva A, Avitia-Domínguez C. Finding the First Potential Inhibitors of Shikimate Kinase from Methicillin Resistant Staphylococcus aureus through Computer-Assisted Drug Design. Molecules 2021; 26:molecules26216736. [PMID: 34771148 PMCID: PMC8587801 DOI: 10.3390/molecules26216736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is an important threat as it causes serious hospital and community acquired infections with deathly outcomes oftentimes, therefore, development of new treatments against this bacterium is a priority. Shikimate kinase, an enzyme in the shikimate pathway, is considered a good target for developing antimicrobial drugs; this is given because of its pathway, which is essential in bacteria whereas it is absent in mammals. In this work, a computer-assisted drug design strategy was used to report the first potentials inhibitors for Shikimate kinase from methicillin-resistant Staphylococcus aureus (SaSK), employing approximately 5 million compounds from ZINC15 database. Diverse filtering criteria, related to druglike characteristics and virtual docking screening in the shikimate binding site, were performed to select structurally diverse potential inhibitors from SaSK. Molecular dynamics simulations were performed to elucidate the dynamic behavior of each SaSK–ligand complex. The potential inhibitors formed important interactions with residues that are crucial for enzyme catalysis, such as Asp37, Arg61, Gly82, and Arg138. Therefore, the compounds reported provide valuable information and can be seen as the first step toward developing SaSK inhibitors in the search of new drugs against MRSA.
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Affiliation(s)
- Lluvia Rios-Soto
- Facultad de Medicina y Nutrición, Universidad Juárez del Estado de Durango, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (L.R.-S.); (J.C.-M.)
| | - Alfredo Téllez-Valencia
- Facultad de Medicina y Nutrición, Universidad Juárez del Estado de Durango, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (L.R.-S.); (J.C.-M.)
- Correspondence: (A.T.-V.); (C.A.-D.); Tel./Fax: +52(618)8271382 (A.T.-V. & C.A.-D.)
| | - Erick Sierra-Campos
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango, Av. Artículo 123 S/N Fracc. Filadelfia, Gómez Palacio, Durango 35010, Mexico; (E.S.-C.); (M.V.-S.)
| | - Mónica Valdez-Solana
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango, Av. Artículo 123 S/N Fracc. Filadelfia, Gómez Palacio, Durango 35010, Mexico; (E.S.-C.); (M.V.-S.)
| | - Jorge Cisneros-Martínez
- Facultad de Medicina y Nutrición, Universidad Juárez del Estado de Durango, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (L.R.-S.); (J.C.-M.)
| | - Marcelo Gómez Palacio-Gastélum
- Facultad de Odontología, Universidad Juárez del Estado de Durango, Predio Canoas S/N, Los Angeles, Durango 34070, Mexico;
| | - Adriana Castillo-Villanueva
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de Mexico 04530, Mexico;
| | - Claudia Avitia-Domínguez
- Facultad de Medicina y Nutrición, Universidad Juárez del Estado de Durango, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (L.R.-S.); (J.C.-M.)
- Correspondence: (A.T.-V.); (C.A.-D.); Tel./Fax: +52(618)8271382 (A.T.-V. & C.A.-D.)
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Abstract
Bacterial tyrosine kinases (BY-kinases) and shikimate kinases (SKs) comprise two structurally divergent P-loop containing enzyme families that share similar catalytic site geometries, most notably with respect to their Walker-A, Walker-B, and DxD motifs. We had previously demonstrated that in BY-kinases, a specific interaction between the Walker-A and Walker-B motifs, driven by the conserved “catalytic” lysine housed on the former, leads to a conformation that is unable to efficiently coordinate Mg2+•ATP and is therefore incapable of chemistry. Here, using enhanced sampling molecular dynamics simulations, we demonstrate that structurally similar interactions between the Walker-A and Walker-B motifs, also mediated by the catalytic lysine, stabilize a state in SKs that deviates significantly from one that is necessary for the optimal coordination of Mg2+•ATP. This structural role of the Walker-A lysine is a general feature in SKs and is found to be present in members that encode a Walker-B sequence characteristic of the family (Coxiella burnetii SK), and in those that do not (Mycobacterium tuberculosis SK). Thus, the structural role of the Walker-A lysine in stabilizing an inactive state, distinct from its catalytic function, is conserved between two distantly related P-loop containing kinase families, the SKs and the BY-kinases. The universal conservation of this element, and of the key characteristics of its associated interaction partners within the Walker motifs of P-loop containing enzymes, suggests that this structural role of the Walker-A lysine is perhaps a widely deployed regulatory mechanism within this ancient family.
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Affiliation(s)
- Fatlum Hajredini
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY, United States.,PhD Program in Biochemistry, The Graduate Center of CUNY, New York, NY, United States
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY, United States.,PhD Program in Biochemistry, The Graduate Center of CUNY, New York, NY, United States.,PhD Program in Chemistry, The Graduate Center of CUNY, New York, NY, United States.,PhD Program in Physics, The Graduate Center of CUNY, New York, NY, United States
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Sahu PK, Mohapatra PK, Rajani DP, Raval MK. Structure-based Discovery of Narirutin as a Shikimate kinase Inhibitor with Anti-tubercular Potency. Curr Comput Aided Drug Des 2019; 16:523-529. [PMID: 31654517 DOI: 10.2174/1573409915666191025112150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/05/2019] [Accepted: 10/10/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Shikimate pathway is essential for tubercular bacillus but it is absent in mammals. Therefore, Shikimate kinase and other enzymes in the pathway are potential targets for the development of novel anti-tuberculosis drugs. OBJECTIVE In the present study, Shikimate kinase is selected as the target for in silico screening of phytochemicals with an aim to discover a novel herbal drug against Mycobacterium tuberculosis (Mtb). METHODS A structure-based drug discovery approach is undertaken for the execution of the objective. Virtual screening of phytochemical database NPACT against the target, Shikimate kinase (PDB ID 3BAF), is carried out followed by toxicity and drug-likeness filtration. Finally, a lead, narirutin was selected for in vitro anti-tubercular study. RESULTS Narirutin, present in citrus fruits, emerges as the lead. It is considered to be non-toxic with predicted high LD50 value, 12000 mg/kg body weight. The phytochemical is tested for its antitubercular activity in vitro. It has MIC99 62.5 μg/mL against the MtbH37Rv strain. CONCLUSION This is the first-ever report to show anti-tuberculosis potency of narirutin.
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Affiliation(s)
- Pramod Kumar Sahu
- Department of Chemistry, Gangadhar Meher University, Sambalpur, 768004, Odisha, India
| | - Pranab Kishor Mohapatra
- Department of Chemistry, CV Raman College of Engineering, Bidyanagar, Mahura, Janla, Bhubaneswar 752054, Odisha, India
| | - Dhanji Popatbhai Rajani
- Microcare Laboratory and Tuberculosis Research Center, 105, Manthan Point, Unapani Road, Lal Darwaja, Surat - 395003, Gujarat, India
| | - Mukesh Kumar Raval
- Department of Chemistry, Gangadhar Meher University, Sambalpur, 768004, Odisha, India
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Schoenenberger B, Wszolek A, Meier R, Brundiek H, Obkircher M, Wohlgemuth R. Recombinant AroL-Catalyzed Phosphorylation for the Efficient Synthesis of Shikimic Acid 3-Phosphate. Biotechnol J 2018; 13:e1700529. [PMID: 29697210 DOI: 10.1002/biot.201700529] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 04/03/2018] [Indexed: 01/01/2023]
Abstract
Shikimic acid 3-phosphate, as a central metabolite of the shikimate pathway, is of high interest as enzyme substrate for 5-enolpyruvoyl-shikimate 3-phosphate synthase, a drug target in infectious diseases and a prime enzyme target for the herbicide glyphosate. As the important substrate shikimic acid 3-phosphate is only accessible via a chemical multi-step route, a new straightforward preparative one-step enzymatic phosphorylation of shikimate using a stable recombinant shikimate kinase has been developed for the selective phosphorylation of shikimate in the 3-position. Highly active shikimate kinase is produced by straightforward expression of a synthetic aroL gene in Escherichia coli. The time course of the shikimate kinase-catalyzed phosphorylation is investigated by 1 H- and 31 P-NMR, using the phosphoenolpyruvate/pyruvate kinase system for the regeneration of the ATP cofactor. This enables the development of a quantitative biocatalytic 3-phosphorylation of shikimic acid. After a standard workup procedure, a good yield of shikimic acid 3-phosphate, with high HPLC- and NMR purity, is obtained. This efficient biocatalytic synthesis of shikimic acid 3-phosphate is superior to any other method and has been successfully scaled up to multi-gram scale.
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Affiliation(s)
| | - Agata Wszolek
- Enzymicals, Walther-Rathenau-Strasse 49a, 17489, Greifswald, Germany
| | - Roland Meier
- Sigma-Aldrich, Member of Merck Group, Industriestrasse 25, CH-9470, Buchs, Switzerland
| | - Henrike Brundiek
- Enzymicals, Walther-Rathenau-Strasse 49a, 17489, Greifswald, Germany
| | - Markus Obkircher
- Sigma-Aldrich, Member of Merck Group, Industriestrasse 25, CH-9470, Buchs, Switzerland
| | - Roland Wohlgemuth
- Sigma-Aldrich, Member of Merck Group, Industriestrasse 25, CH-9470, Buchs, Switzerland
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Sutton KA, Breen J, MacDonald U, Beanan JM, Olson R, Russo TA, Schultz LW, Umland TC. Structure of shikimate kinase, an in vivo essential metabolic enzyme in the nosocomial pathogen Acinetobacter baumannii, in complex with shikimate. ACTA ACUST UNITED AC 2015; 71:1736-44. [PMID: 26249354 DOI: 10.1107/s139900471501189x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 06/22/2015] [Indexed: 11/10/2022]
Abstract
Acinetobacter baumannii is an opportunistic Gram-negative pathogen that is an important cause of healthcare-associated infections exhibiting high mortality rates. Clinical isolates of multidrug-resistant (MDR) and extremely drug-resistant (XDR) A. baumannii strains are increasingly being observed. Compounding this concern is the dearth of new antibacterial agents in late-stage development that are effective against MDR and XDR A. baumannii. As part of an effort to address these concerns, two genes (aroA and aroC) of the shikimate pathway have previously been determined to be essential for the growth and survival of A. baumannii during host infection (i.e. to be essential in vivo). This study expands upon these results by demonstrating that the A. baumannii aroK gene, encoding shikimate kinase (SK), is also essential in vivo in a rat soft-tissue infection model. The crystal structure of A. baumannii SK in complex with the substrate shikimate and a sulfate ion that mimics the binding interactions expected for the β-phosphate of ATP was then determined to 1.91 Å resolution and the enzyme kinetics were characterized. The flexible shikimate-binding domain and LID region are compared with the analogous regions in other SK crystal structures. The impact of structural differences and sequence divergence between SKs from pathogenic bacteria that may influence antibiotic-development efforts is discussed.
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Affiliation(s)
- Kristin A Sutton
- Hauptman-Woodward Medical Research Institute, Buffalo, NY 14203, USA
| | - Jennifer Breen
- Hauptman-Woodward Medical Research Institute, Buffalo, NY 14203, USA
| | - Ulrike MacDonald
- Department of Medicine and The Witebsky Center for Microbial Pathogenesis, University at Buffalo, State University of New York, Buffalo, NY 14214, USA
| | - Janet M Beanan
- Department of Medicine and The Witebsky Center for Microbial Pathogenesis, University at Buffalo, State University of New York, Buffalo, NY 14214, USA
| | - Ruth Olson
- Department of Medicine and The Witebsky Center for Microbial Pathogenesis, University at Buffalo, State University of New York, Buffalo, NY 14214, USA
| | - Thomas A Russo
- Department of Medicine and The Witebsky Center for Microbial Pathogenesis, University at Buffalo, State University of New York, Buffalo, NY 14214, USA
| | - L Wayne Schultz
- Hauptman-Woodward Medical Research Institute, Buffalo, NY 14203, USA
| | - Timothy C Umland
- Hauptman-Woodward Medical Research Institute, Buffalo, NY 14203, USA
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Krell T, Maclean J, Boam DJ, Cooper A, Resmini M, Brocklehurst K, Kelly SM, Price NC, Lapthorn AJ, Coggins JR. Biochemical and X-ray crystallographic studies on shikimate kinase: the important structural role of the P-loop lysine. Protein Sci 2001; 10:1137-49. [PMID: 11369852 PMCID: PMC2374015 DOI: 10.1110/ps.52501] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2000] [Revised: 03/08/2001] [Accepted: 03/12/2001] [Indexed: 10/14/2022]
Abstract
Shikimate kinase, despite low sequence identity, has been shown to be structurally a member of the nucleoside monophosphate (NMP) kinase family, which includes adenylate kinase. In this paper we have explored the roles of residues in the P-loop of shikimate kinase, which forms the binding site for nucleotides and is one of the most conserved structural features in proteins. In common with many members of the P-loop family, shikimate kinase contains a cysteine residue 2 amino acids upstream of the essential lysine residue; the side chains of these residues are shown to form an ion pair. The C13S mutant of shikimate kinase was found to be enzymatically active, whereas the K15M mutant was inactive. However, the latter mutant had both increased thermostability and affinity for ATP when compared to the wild-type enzyme. The structure of the K15M mutant protein has been determined at 1.8 A, and shows that the organization of the P-loop and flanking regions is heavily disturbed. This indicates that, besides its role in catalysis, the P-loop lysine also has an important structural role. The structure of the K15M mutant also reveals that the formation of an additional arginine/aspartate ion pair is the most likely reason for its increased thermostability. From studies of ligand binding it appears that, like adenylate kinase, shikimate kinase binds substrates randomly and in a synergistic fashion, indicating that the two enzymes have similar catalytic mechanisms.
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Affiliation(s)
- T Krell
- Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow G12 8QQ, Scotland, UK
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