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Abuhammad A, Laurieri N, Rice A, Lowe ED, Singh N, Naser SM, Ratrout SS, Churchill GC. Structural and biochemical analysis of human inositol monophosphatase-1 inhibition by ebselen. J Biomol Struct Dyn 2023; 41:14036-14048. [PMID: 36762717 DOI: 10.1080/07391102.2023.2176925] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/30/2023] [Indexed: 02/11/2023]
Abstract
Bipolar disorder is a major psychiatric disorder associated with cognitive impairment and a high suicide rate. Frontline therapy for this condition includes lithium (Li+)-containing treatments that can exert severe side effects. One target of Li+ is inositol monophosphatase-1 (IMPase1); inhibition of IMPase1 through small-molecule compounds may provide an alternative treatment for bipolar disorder. One such compound is the anti-inflammatory drug ebselen, which is well tolerated and safe; however, ebselen's exact mechanism of action in IMPase1 inhibition is not fully understood, preventing rational design of IMPase1 inhibitors. To fill this gap, we performed crystallographic and biochemical studies to investigate how ebselen inhibits IMPase1. We obtained a structure of IMPase1 in space group P21 after treatment with ebselen that revealed three key active-site loops (residues 33-44, 70-79, and 161-165) that are either disordered or in multiple conformations, supporting a hypothesis whereby dynamic conformational changes may be important for catalysis and ebselen inhibition. Using the thermal shift assay, we confirmed that ebselen significantly destabilizes the enzyme. Molecular docking suggests that ebselen could bind in the vicinity of His217. Investigation of the role of IMPase1 residues His217 and Cys218 suggests that inhibition of IMPase1 by ebselen may not be mediated via covalent modification of the active-site cysteine (Cys218) and is not affected by the covalent modification of other cysteine residues in the structure. Our results suggest that effects previously ascribed to ebselen-dependent inhibition likely result from disruption of essential active-site architecture, preventing activation of the IMPase1-Mg2+ complex.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Areej Abuhammad
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Nicola Laurieri
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Alistair Rice
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Edward D Lowe
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Nisha Singh
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Saleem M Naser
- Research and Development Department, APIs Division, Hikma Pharmaceutical Co. Ltd, Amman, Jordan
| | - Samer S Ratrout
- Research and Development Department, APIs Division, Hikma Pharmaceutical Co. Ltd, Amman, Jordan
| | - Grant C Churchill
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
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2
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Karagianni E, Kontomina E, Lowe ED, Athanasopoulos K, Papanikolaou G, Garefalaki V, Kotseli V, Zaliou S, Grimaud T, Arvaniti K, Tsatiri M, Fakis G, Glenn AE, Roversi P, Abuhammad A, Ryan A, Sim RB, Sim E, Boukouvala S. Fusarium verticillioides
NAT1
(
FDB2
)
N
‐malonyltransferase is structurally, functionally and phylogenetically distinct from its
N
‐acetyltransferase (
NAT
) homologues. FEBS J 2022; 290:2412-2436. [PMID: 36178468 DOI: 10.1111/febs.16642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 08/22/2022] [Accepted: 09/29/2022] [Indexed: 12/01/2022]
Abstract
Fusarium endophytes damage cereal crops and contaminate produce with mycotoxins. Those fungi overcome the main chemical defence of host via detoxification by a malonyl-CoA-dependent enzyme homologous to xenobiotic metabolizing arylamine N-acetyltransferase (NAT). In Fusarium verticillioides (teleomorph Gibberella moniliformis, GIBMO), this N-malonyltransferase activity is attributed to (GIBMO)NAT1, and the fungus has two additional isoenzymes, (GIBMO)NAT3 (N-acetyltransferase) and (GIBMO)NAT2 (unknown function). We present the crystallographic structure of (GIBMO)NAT1, also modelling other fungal NAT homologues. Monomeric (GIBMO)NAT1 is distinctive, with access to the catalytic core through two "tunnel-like" entries separated by a "bridge-like" helix. In the quaternary arrangement, (GIBMO)NAT1 monomers interact in pairs along an extensive interface whereby one entry of each monomer is covered by the N-terminus of the other monomer. Although monomeric (GIBMO)NAT1 apparently accommodates acetyl-CoA better than malonyl-CoA, dimerization changes the active site to allow malonyl-CoA to reach the catalytic triad (Cys110, His158 and Asp173) via the single uncovered entry, and anchor its terminal carboxyl-group via hydrogen bonds to Arg109, Asn157 and Thr261. Lacking a terminal carboxyl-group, acetyl-CoA cannot form such stabilizing interactions, while longer acyl-CoAs enter the active site but cannot reach catalytic Cys. Other NAT isoenzymes lack such structural features, with (GIBMO)NAT3 resembling bacterial NATs and (GIBMO)NAT2 adopting a structure intermediate between (GIBMO)NAT1 and (GIBMO)NAT3. Biochemical assays confirmed differential donor substrate preference of (GIBMO)NAT isoenzymes, with phylogenetic analysis demonstrating evolutionary separation. Given the role of (GIBMO)NAT1 in enhancing Fusarium pathogenicity, unravelling the structure and function of this enzyme may benefit research into more targeted strategies for pathogen control.
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Affiliation(s)
- Eleni‐Pavlina Karagianni
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
- University of Oxford Department of Pharmacology Oxford U.K
| | - Evanthia Kontomina
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
- University of Oxford Department of Pharmacology Oxford U.K
| | - Edward D. Lowe
- University of Oxford Department of Biochemistry Oxford U.K
| | | | - Georgia Papanikolaou
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Vasiliki Garefalaki
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Varvara Kotseli
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Sofia Zaliou
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
- Kingston University London, Faculty of Science, Engineering and Computing Kingston‐upon‐Thames U.K
| | - Tom Grimaud
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Konstantina Arvaniti
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Maria‐Aggeliki Tsatiri
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
| | - Giannoulis Fakis
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
- University of Oxford Department of Pharmacology Oxford U.K
| | - Anthony E. Glenn
- U.S. Department of Agriculture, Agricultural Research Service, National Poultry Research Center, Toxicology & Mycotoxin Research Unit Athens GA U.S.A
| | - Pietro Roversi
- Institute of Agricultural Biology and Biotechnology, IBBA‐CNR Unit of Milan Milan Italy
- Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology University of Leicester U.K
| | - Areej Abuhammad
- University of Oxford Department of Pharmacology Oxford U.K
- The University of Jordan, School of Pharmacy Amman Jordan
| | - Ali Ryan
- University of Oxford Department of Pharmacology Oxford U.K
- Kingston University London, Faculty of Science, Engineering and Computing Kingston‐upon‐Thames U.K
- Northumbria University, Department of Applied Sciences Newcastle‐upon‐Tyne U.K
| | - Robert B. Sim
- University of Oxford Department of Pharmacology Oxford U.K
| | - Edith Sim
- University of Oxford Department of Pharmacology Oxford U.K
- Kingston University London, Faculty of Science, Engineering and Computing Kingston‐upon‐Thames U.K
| | - Sotiria Boukouvala
- Democritus University of Thrace Department of Molecular Biology and Genetics Alexandroupolis Greece
- University of Oxford Department of Pharmacology Oxford U.K
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3
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Smaldone G, Ruggiero A, Balasco N, Abuhammad A, Autiero I, Caruso D, Esposito D, Ferraro G, Gelardi ELM, Moreira M, Quareshy M, Romano M, Saaret A, Selvam I, Squeglia F, Troisi R, Kroon-Batenburg LMJ, Esposito L, Berisio R, Vitagliano L. The non-swapped monomeric structure of the arginine-binding protein from Thermotoga maritima. Acta Crystallogr F Struct Biol Commun 2019; 75:707-713. [PMID: 31702584 DOI: 10.1107/s2053230x1901464x] [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: 09/25/2019] [Accepted: 10/29/2019] [Indexed: 01/07/2023] Open
Abstract
Domain swapping is a widespread oligomerization process that is observed in a large variety of protein families. In the large superfamily of substrate-binding proteins, non-monomeric members have rarely been reported. The arginine-binding protein from Thermotoga maritima (TmArgBP), a protein endowed with a number of unusual properties, presents a domain-swapped structure in its dimeric native state in which the two polypeptide chains mutually exchange their C-terminal helices. It has previously been shown that mutations in the region connecting the last two helices of the TmArgBP structure lead to the formation of a variety of oligomeric states (monomers, dimers, trimers and larger aggregates). With the aim of defining the structural determinants of domain swapping in TmArgBP, the monomeric form of the P235GK mutant has been structurally characterized. Analysis of this arginine-bound structure indicates that it consists of a closed monomer with its C-terminal helix folded against the rest of the protein, as typically observed for substrate-binding proteins. Notably, the two terminal helices are joined by a single nonhelical residue (Gly235). Collectively, the present findings indicate that extending the hinge region and conferring it with more conformational freedom makes the formation of a closed TmArgBP monomer possible. On the other hand, the short connection between the helices may explain the tendency of the protein to also adopt alternative oligomeric states (dimers, trimers and larger aggregates). The data reported here highlight the importance of evolutionary control to avoid the uncontrolled formation of heterogeneous and potentially harmful oligomeric species through domain swapping.
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Affiliation(s)
| | - Alessia Ruggiero
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Nicole Balasco
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Areej Abuhammad
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Ida Autiero
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Daniela Caruso
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Davide Esposito
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Giarita Ferraro
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | | | - Miguel Moreira
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Mussa Quareshy
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Maria Romano
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Annica Saaret
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Irwin Selvam
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Flavia Squeglia
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Romualdo Troisi
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | | | - Luciana Esposito
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Rita Berisio
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
| | - Luigi Vitagliano
- AIC School Crystallographic Information Fiesta 2019, Naples, Italy
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4
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Al-Barghouthy EY, Abuhammad A, Taha MO. QSAR-guided pharmacophore modeling and subsequent virtual screening identify novel TYK2 inhibitor. Med Chem Res 2019. [DOI: 10.1007/s00044-019-02377-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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5
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Abuhammad A. The first protein crystallography project in Jordan. Acta Crystallogr A Found Adv 2017. [DOI: 10.1107/s2053273317081839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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6
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Ryan A, Polycarpou E, Lack NA, Evangelopoulos D, Sieg C, Halman A, Bhakta S, Eleftheriadou O, McHugh TD, Keany S, Lowe ED, Ballet R, Abuhammad A, Jacobs WR, Ciulli A, Sim E. Investigation of the mycobacterial enzyme HsaD as a potential novel target for anti-tubercular agents using a fragment-based drug design approach. Br J Pharmacol 2017; 174:2209-2224. [PMID: 28380256 PMCID: PMC5481647 DOI: 10.1111/bph.13810] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 03/22/2017] [Accepted: 03/24/2017] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE With the emergence of extensively drug-resistant tuberculosis, there is a need for new anti-tubercular drugs that work through novel mechanisms of action. The meta cleavage product hydrolase, HsaD, has been demonstrated to be critical for the survival of Mycobacterium tuberculosis in macrophages and is encoded in an operon involved in cholesterol catabolism, which is identical in M. tuberculosis and M. bovis BCG. EXPERIMENTAL APPROACH We generated a mutant strain of M. bovis BCG with a deletion of hsaD and tested its growth on cholesterol. Using a fragment based approach, over 1000 compounds were screened by a combination of differential scanning fluorimetry, NMR spectroscopy and enzymatic assay with pure recombinant HsaD to identify potential inhibitors. We used enzymological and structural studies to investigate derivatives of the inhibitors identified and to test their effects on growth of M. bovis BCG and M. tuberculosis. KEY RESULTS The hsaD deleted strain was unable to grow on cholesterol as sole carbon source but did grow on glucose. Of seven chemically distinct 'hits' from the library, two chemical classes of fragments were found to bind in the vicinity of the active site of HsaD by X-ray crystallography. The compounds also inhibited growth of M. tuberculosis on cholesterol. The most potent inhibitor of HsaD was also found to be the best inhibitor of mycobacterial growth on cholesterol-supplemented minimal medium. CONCLUSIONS AND IMPLICATIONS We propose that HsaD is a novel therapeutic target, which should be fully exploited in order to design and discover new anti-tubercular drugs. LINKED ARTICLES This article is part of a themed section on Drug Metabolism and Antibiotic Resistance in Micro-organisms. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.14/issuetoc.
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Affiliation(s)
- Ali Ryan
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
| | - Elena Polycarpou
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
| | - Nathan A Lack
- Department of PharmacologyUniversity of OxfordOxfordUK
- School of MedicineKoç UniversityIstanbulTurkey
| | - Dimitrios Evangelopoulos
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological SciencesBirkbeck, University of LondonLondonUK
- Centre for Clinical MicrobiologyUniversity College London, Royal Free CampusLondonUK
- Mycobacterial Metabolism and Antibiotic Research LaboratoryThe Francis Crick Institute, Mill Hill LaboratoryLondonUK
| | - Christian Sieg
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
| | - Alice Halman
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
| | - Sanjib Bhakta
- Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological SciencesBirkbeck, University of LondonLondonUK
| | - Olga Eleftheriadou
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
| | - Timothy D McHugh
- Centre for Clinical MicrobiologyUniversity College London, Royal Free CampusLondonUK
| | | | - Edward D Lowe
- Department of BiochemistryUniversity of OxfordOxfordUK
| | - Romain Ballet
- Department of PharmacologyUniversity of OxfordOxfordUK
| | | | - William R Jacobs
- Department of Microbiology and ImmunologyHoward Hughes Medical Institute, Albert Einstein College of MedicineBronxNew YorkUSA
| | - Alessio Ciulli
- Department of ChemistryUniversity of CambridgeCambridgeUK
- Division of Biological Chemistry & Drug Discovery, School of Life SciencesUniversity of Dundee, James Black CentreDundeeUK
| | - Edith Sim
- Faculty of Science, Engineering and ComputingKingston University LondonKingston upon ThamesUK
- Department of PharmacologyUniversity of OxfordOxfordUK
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7
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Abuhammad A, Al-Aqtash RA, Anson BJ, Mesecar AD, Taha MO. Computational modeling of the bat HKU4 coronavirus 3CL pro inhibitors as a tool for the development of antivirals against the emerging Middle East respiratory syndrome (MERS) coronavirus. J Mol Recognit 2017; 30. [PMID: 28608547 PMCID: PMC7166879 DOI: 10.1002/jmr.2644] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 05/01/2017] [Accepted: 05/09/2017] [Indexed: 12/22/2022]
Abstract
The Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging virus that poses a major challenge to clinical management. The 3C‐like protease (3CLpro) is essential for viral replication and thus represents a potential target for antiviral drug development. Presently, very few data are available on MERS‐CoV 3CLpro inhibition by small molecules. We conducted extensive exploration of the pharmacophoric space of a recently identified set of peptidomimetic inhibitors of the bat HKU4‐CoV 3CLpro. HKU4‐CoV 3CLpro shares high sequence identity (81%) with the MERS‐CoV enzyme and thus represents a potential surrogate model for anti‐MERS drug discovery. We used 2 well‐established methods: Quantitative structure‐activity relationship (QSAR)‐guided modeling and docking‐based comparative intermolecular contacts analysis. The established pharmacophore models highlight structural features needed for ligand recognition and revealed important binding‐pocket regions involved in 3CLpro‐ligand interactions. The best models were used as 3D queries to screen the National Cancer Institute database for novel nonpeptidomimetic 3CLpro inhibitors. The identified hits were tested for HKU4‐CoV and MERS‐CoV 3CLpro inhibition. Two hits, which share the phenylsulfonamide fragment, showed moderate inhibitory activity against the MERS‐CoV 3CLpro and represent a potential starting point for the development of novel anti‐MERS agents. To the best of our knowledge, this is the first pharmacophore modeling study supported by in vitro validation on the MERS‐CoV 3CLpro. Highlights MERS‐CoV is an emerging virus that is closely related to the bat HKU4‐CoV. 3CLpro is a potential drug target for coronavirus infection. HKU4‐CoV 3CLpro is a useful surrogate model for the identification of MERS‐CoV 3CLpro enzyme inhibitors. dbCICA is a very robust modeling method for hit identification. The phenylsulfonamide scaffold represents a potential starting point for MERS coronavirus 3CLpro inhibitors development.
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Affiliation(s)
- Areej Abuhammad
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Rua'a A Al-Aqtash
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
| | - Brandon J Anson
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA
| | - Andrew D Mesecar
- Department of Biological Sciences, Purdue University, West Lafayette, IN, USA.,Department of Chemistry, Purdue University, West Lafayette, IN, USA.,Centers for Cancer Research & Drug Discovery, Purdue University, West Lafayette, IN, USA
| | - Mutasem O Taha
- Department of Pharmaceutical Sciences, School of Pharmacy, The University of Jordan, Amman, Jordan
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8
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Abuhammad A. Cholesterol metabolism: a potential therapeutic target in Mycobacteria. Br J Pharmacol 2017; 174:2194-2208. [PMID: 28002883 DOI: 10.1111/bph.13694] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/06/2016] [Accepted: 12/16/2016] [Indexed: 12/14/2022] Open
Abstract
Tuberculosis (TB), although a curable disease, is still one of the most difficult infections to treat. Mycobacterium tuberculosis infects 10 million people worldwide and kills 1.5 million people each year. Reactivation of a latent infection is the major cause of TB. Cholesterol is a critical carbon source during latent infection. Catabolism of cholesterol contributes to the pool of propionyl-CoA, a precursor that is incorporated into lipid virulence factors. The M. tuberculosis genome contains a large regulon of cholesterol catabolic genes suggesting that the microorganism can utilize host sterol for infection and persistence. The protein products of these genes present ideal targets for rational drug discovery programmes. This review summarizes the development of enzyme inhibitors targeting the cholesterol pathway in M. tuberculosis. This knowledge is essential for the discovery of novel agents to treat M. tuberculosis infection. LINKED ARTICLES This article is part of a themed section on Drug Metabolism and Antibiotic Resistance in Micro-organisms. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.14/issuetoc.
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9
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Abstract
INTRODUCTION Type-II diabetes mellitus (T2DM) is a complex chronic disease that represents a major therapeutic challenge. Despite extensive efforts in T2DM drug development, therapies remain unsatisfactory. Currently, there are many novel and important antidiabetic drug targets under investigation by many research groups worldwide. One of the main challenges to develop effective orally active hypoglycemic agents is off-target effects. Computational tools have impacted drug discovery at many levels. One of the earliest methods is quantitative structure-activity relationship (QSAR) studies. QSAR strategies help medicinal chemists understand the relationship between hypoglycemic activity and molecular properties. Hence, QSAR may hold promise in guiding the synthesis of specifically designed novel ligands that demonstrate high potency and target selectivity. AREAS COVERED This review aims to provide an overview of the QSAR strategies used to model antidiabetic agents. In particular, this review focuses on drug targets that raised recent scientific interest and/or led to successful antidiabetic agents in the market. Special emphasis has been made on studies that led to the identification of novel antidiabetic scaffolds. EXPERT OPINION Computer-aided molecular design and discovery techniques like QSAR have a great potential in designing leads against complex diseases such as T2DM. Combined with other in silico techniques, QSAR can provide more useful and rational insights to facilitate the discovery of novel compounds. However, since T2DM is a complex disease that includes several faulty biological targets, multi-target QSAR studies are recommended in the future to achieve efficient antidiabetic therapies.
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Affiliation(s)
- Areej Abuhammad
- a Department of Pharmaceutical Sciences, Faculty of Pharmacy , The University of Jordan , Amman 11942 , Jordan
| | - Mutasem O Taha
- a Department of Pharmaceutical Sciences, Faculty of Pharmacy , The University of Jordan , Amman 11942 , Jordan
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10
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Sim E, Abuhammad A, Ryan A. Arylamine N-acetyltransferases: from drug metabolism and pharmacogenetics to drug discovery. Br J Pharmacol 2014; 171:2705-25. [PMID: 24467436 PMCID: PMC4158862 DOI: 10.1111/bph.12598] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 08/15/2013] [Accepted: 08/26/2013] [Indexed: 12/12/2022] Open
Abstract
Arylamine N-acetyltransferases (NATs) are polymorphic drug-metabolizing enzymes, acetylating arylamine carcinogens and drugs including hydralazine and sulphonamides. The slow NAT phenotype increases susceptibility to hydralazine and isoniazid toxicity and to occupational bladder cancer. The two polymorphic human NAT loci show linkage disequilibrium. All mammalian Nat genes have an intronless open reading frame and non-coding exons. The human gene products NAT1 and NAT2 have distinct substrate specificities: NAT2 acetylates hydralazine and human NAT1 acetylates p-aminosalicylate (p-AS) and the folate catabolite para-aminobenzoylglutamate (p-abaglu). Human NAT2 is mainly in liver and gut. Human NAT1 and its murine homologue are in many adult tissues and in early embryos. Human NAT1 is strongly expressed in oestrogen receptor-positive breast cancer and may contribute to folate and acetyl CoA homeostasis. NAT enzymes act through a catalytic triad of Cys, His and Asp with the architecture of the active site-modulating specificity. Polymorphisms may cause unfolded protein. The C-terminus helps bind acetyl CoA and differs among NATs including prokaryotic homologues. NAT in Salmonella typhimurium supports carcinogen activation and NAT in mycobacteria metabolizes isoniazid with polymorphism a minor factor in isoniazid resistance. Importantly, nat is in a gene cluster essential for Mycobacterium tuberculosis survival inside macrophages. NAT inhibitors are a starting point for novel anti-tuberculosis drugs. Human NAT1-specific inhibitors may act in biomarker detection in breast cancer and in cancer therapy. NAT inhibitors for co-administration with 5-aminosalicylate (5-AS) in inflammatory bowel disease has prompted ongoing investigations of azoreductases in gut bacteria which release 5-AS from prodrugs including balsalazide.
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Affiliation(s)
- E Sim
- Faculty of Science Engineering and Computing, Kingston University, Kingston, UK; Department of Pharmacology, Oxford University, Oxford, UK
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11
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Cocaign A, Kubiak X, Xu X, Garnier G, Li de la Sierra-Gallay I, Chi-Bui L, Dairou J, Busi F, Abuhammad A, Haouz A, Dupret JM, Herrmann JL, Rodrigues-Lima F. Structural and functional characterization of an arylamineN-acetyltransferase from the pathogenMycobacterium abscessus: differences from other mycobacterial isoforms and implications for selective inhibition. ACTA ACUST UNITED AC 2014; 70:3066-79. [DOI: 10.1107/s1399004714021282] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 09/24/2014] [Indexed: 11/10/2022]
Abstract
Mycobacterium abscessusis the most pathogenic rapid-growing mycobacterium and is one of the most resistant organisms to chemotherapeutic agents. However, structural and functional studies ofM. abscessusproteins that could modify/inactivate antibiotics remain nonexistent. Here, the structural and functional characterization of an arylamineN-acetyltransferase (NAT) fromM. abscessus[(MYCAB)NAT1] are reported. This novel prokaryotic NAT displays significantN-acetyltransferase activity towards aromatic substrates, including antibiotics such as isoniazid andp-aminosalicylate. The enzyme is endogenously expressed and functional in both the rough and smoothM. abscessusmorphotypes. The crystal structure of (MYCAB)NAT1 at 1.8 Å resolution reveals that it is more closely related toNocardia farcinicaNAT than to mycobacterial isoforms. In particular, structural and physicochemical differences from other mycobacterial NATs were found in the active site. Peculiarities of (MYCAB)NAT1 were further supported by kinetic and docking studies showing that the enzyme was poorly inhibited by the piperidinol inhibitor of mycobacterial NATs. This study describes the first structure of an antibiotic-modifying enzyme fromM. abscessusand provides bases to better understand the substrate/inhibitor-binding specificities among mycobacterial NATs and to identify/optimize specific inhibitors. These data should also contribute to the understanding of the mechanisms that are responsible for the pathogenicity and extensive chemotherapeutic resistance ofM. abscessus.
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12
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Abuhammad A, Fullam E, Bhakta S, Russell AJ, Morris GM, Finn PW, Sim E. Exploration of piperidinols as potential antitubercular agents. Molecules 2014; 19:16274-90. [PMID: 25310152 PMCID: PMC6271891 DOI: 10.3390/molecules191016274] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/09/2014] [Accepted: 09/24/2014] [Indexed: 12/23/2022] Open
Abstract
Novel drugs to treat tuberculosis are required and the identification of potential targets is important. Piperidinols have been identified as potential antimycobacterial agents (MIC < 5 μg/mL), which also inhibit mycobacterial arylamine N-acetyltransferase (NAT), an enzyme essential for mycobacterial survival inside macrophages. The NAT inhibition involves a prodrug-like mechanism in which activation leads to the formation of bioactive phenyl vinyl ketone (PVK). The PVK fragment selectively forms an adduct with the cysteine residue in the active site. Time dependent inhibition of the NAT enzyme from Mycobacterium marinum (M. marinum) demonstrates a covalent binding mechanism for all inhibitory piperidinol analogues. The structure activity relationship highlights the importance of halide substitution on the piperidinol benzene ring. The structures of the NAT enzymes from M. marinum and M. tuberculosis, although 74% identical, have different residues in their active site clefts and allow the effects of amino acid substitutions to be assessed in understanding inhibitory potency. In addition, we have used the piperidinol 3-dimensional shape and electrostatic properties to identify two additional distinct chemical scaffolds as inhibitors of NAT. While one of the scaffolds has anti-tubercular activity, both inhibit NAT but through a non-covalent mechanism.
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Affiliation(s)
- Areej Abuhammad
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Elizabeth Fullam
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Sanjib Bhakta
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Angela J Russell
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Garrett M Morris
- InhibOx, Oxford Centre for Innovation, New Road, Oxford OX1 1BY, UK
| | - Paul W Finn
- InhibOx, Oxford Centre for Innovation, New Road, Oxford OX1 1BY, UK
| | - Edith Sim
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK.
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Abuhammad A, McDonough M, Brem J, Schofield C, Garman E. "From one seed a whole handful": homologous proteins as seeds in crystallisation. Acta Crystallogr A Found Adv 2014. [DOI: 10.1107/s205327331408855x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
Protein structures have significantly impacted and aided drug discovery efforts. However, it is not enough to know the structure of a protein; it must be the right structure. Small alteration in sequence can lead to different conformations and oligomerization states, cause changes which lead to different active site architecture and also which modify function. Protein crystallization is an essential prerequisite for the determination of protein structures by X-ray crystallography. We have obtained encouraging initial results for a hitherto unexplored crystallization method with the enzyme arylamine N-acetyltransferase from M. tuberculosis (TBNAT). Despite prolonged and varied trials to crystallize TBNAT, an important anti-tubercular drug target, no crystals were obtained. In an alternative approach, cross-seeding of TBNAT protein with micro-crystalline seeds from a homologous NAT from M. marinum (74 % sequence identity (SID)) surprisingly resulted in a single 20 micron sized TBNAT crystal that diffracted to 2.1 Å and allowed for TBNAT structure determination (Abuhammad et al., 2013). To our knowledge, cross-seeding crystallisation using homologous proteins has only been previously successful in cases with more than 85% SID. In this study, we have explored the effect of low sequence homology on cross seeding using β-lactamases with SID as low as 30%. Despite the low SIDs, the results show cross seeding leads to an increase in hits obtained, the identification of new crystallization conditions, shortening of crystallization time and an improvement in the quality of the crystals obtained.
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Abuhammad A, Lowe ED, McDonough MA, Sim E, Garman EF. Structure of arylamineN-acetyltransferase fromM. tuberculosis: triumph over adversity. Acta Crystallogr A 2013. [DOI: 10.1107/s0108767313099273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Abuhammad A, Lowe ED, McDonough MA, Shaw Stewart PD, Kolek SA, Sim E, Garman EF. Structure of arylamineN-acetyltransferase fromMycobacterium tuberculosisdetermined by cross-seeding with the homologous protein fromM. marinum: triumph over adversity. Acta Crystallogr D Biol Crystallogr 2013; 69:1433-46. [DOI: 10.1107/s0907444913015126] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/31/2013] [Indexed: 11/10/2022]
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Abuhammad A, Fullam E, Lowe ED, Staunton D, Kawamura A, Westwood IM, Bhakta S, Garner AC, Wilson DL, Seden PT, Davies SG, Russell AJ, Garman EF, Sim E. Piperidinols that show anti-tubercular activity as inhibitors of arylamine N-acetyltransferase: an essential enzyme for mycobacterial survival inside macrophages. PLoS One 2012; 7:e52790. [PMID: 23285185 PMCID: PMC3532304 DOI: 10.1371/journal.pone.0052790] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 11/21/2012] [Indexed: 11/19/2022] Open
Abstract
Latent M. tuberculosis infection presents one of the major obstacles in the global eradication of tuberculosis (TB). Cholesterol plays a critical role in the persistence of M. tuberculosis within the macrophage during latent infection. Catabolism of cholesterol contributes to the pool of propionyl-CoA, a precursor that is incorporated into cell-wall lipids. Arylamine N-acetyltransferase (NAT) is encoded within a gene cluster that is involved in the cholesterol sterol-ring degradation and is essential for intracellular survival. The ability of the NAT from M. tuberculosis (TBNAT) to utilise propionyl-CoA links it to the cholesterol-catabolism pathway. Deleting the nat gene or inhibiting the NAT enzyme prevents intracellular survival and results in depletion of cell-wall lipids. TBNAT has been investigated as a potential target for TB therapies. From a previous high-throughput screen, 3-benzoyl-4-phenyl-1-methylpiperidinol was identified as a selective inhibitor of prokaryotic NAT that exhibited antimycobacterial activity. The compound resulted in time-dependent irreversible inhibition of the NAT activity when tested against NAT from M. marinum (MMNAT). To further evaluate the antimycobacterial activity and the NAT inhibition of this compound, four piperidinol analogues were tested. All five compounds exert potent antimycobacterial activity against M. tuberculosis with MIC values of 2.3-16.9 µM. Treatment of the MMNAT enzyme with this set of inhibitors resulted in an irreversible time-dependent inhibition of NAT activity. Here we investigate the mechanism of NAT inhibition by studying protein-ligand interactions using mass spectrometry in combination with enzyme analysis and structure determination. We propose a covalent mechanism of NAT inhibition that involves the formation of a reactive intermediate and selective cysteine residue modification. These piperidinols present a unique class of antimycobacterial compounds that have a novel mode of action different from known anti-tubercular drugs.
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Affiliation(s)
- Areej Abuhammad
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Faculty of Pharmacy, University of Jordan, Amman, Jordan
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Elizabeth Fullam
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Edward D. Lowe
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - David Staunton
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Akane Kawamura
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Isaac M. Westwood
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Sanjib Bhakta
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | | | - David L. Wilson
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Peter T. Seden
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Stephen G. Davies
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Angela J. Russell
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Elspeth F. Garman
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Edith Sim
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- Faculty of Science, Engineering and Computing Kingston University, Kingston, United Kingdom
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Abuhammad A, Fullam E, Westwood I, Russell A, Davies S, Sim E. Structural studies on novel antitubercular targets. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311092762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abuhammad A, Lack N, Schweichler J, Staunton D, Sim RB, Sim E. Improvement of the expression and purification of Mycobacterium tuberculosis arylamine N-acetyltransferase (TBNAT) a potential target for novel anti-tubercular agents. Protein Expr Purif 2011; 80:246-52. [PMID: 21767648 DOI: 10.1016/j.pep.2011.06.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 06/30/2011] [Indexed: 10/18/2022]
Abstract
Arylamine N-acetyltransferase from Mycobacterium tuberculosis (TBNAT) has been proposed as a drug target for latent tuberculosis treatment. The enzyme is essential for the survival of the mycobacterium in macrophages. However, TBNAT has been very difficult to generate as a soluble protein. In this work we describe production of soluble recombinant TBNAT at a reasonable yield achieved by subcloning the tbnat gene with a purification His-tag into the pVLT31 plasmid, and subsequent optimisation of the induction conditions. The expression system results in soluble protein optimised upon extended (60 h) low level isopropyl β-D-1-thiogalactopyranoside level induction (100 μM) at a temperature of 15 °C. The level of TBNAT expression obtained in E. coli has been significantly improved from ∼2 mg to a final yield of up to 16 mg per litre of culture at a purity level suitable for structural studies. The molecular mass of 31310 Da was confirmed using mass spectroscopy and the oligomerisation state was determined. The stability of TBNAT in different buffer systems was investigated by thermal shift assays and sufficient protein is now available for the screening of chemical libraries for inhibitors.
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Affiliation(s)
- Areej Abuhammad
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX13QT, UK
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Fullam E, Abuhammad A, Wilson DL, Anderton MC, Davies SG, Russell AJ, Sim E. Analysis of β-amino alcohols as inhibitors of the potential anti-tubercular target N-acetyltransferase. Bioorg Med Chem Lett 2010; 21:1185-90. [PMID: 21251821 DOI: 10.1016/j.bmcl.2010.12.099] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 12/14/2010] [Accepted: 12/18/2010] [Indexed: 10/18/2022]
Abstract
The synthesis and inhibitory potencies of a novel series of β-amino alcohols, based on the hit-compound 3-[3'-(4''-cyclopent-2'''-en-1'''-ylphenoxy)-2'-hydroxypropyl]-5,5 dimethylimidazolidine-2,4-dione as specific inhibitors of mycobacterial N-acetyltransferase (NAT) enzymes are reported. Effects of synthesised compounds on growth of Mycobacterium tuberculosis have been determined.
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Affiliation(s)
- Elizabeth Fullam
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
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Fullam E, Kawamura A, Wilkinson H, Abuhammad A, Westwood I, Sim E. Comparison of the Arylamine N-acetyltransferase from Mycobacterium marinum and Mycobacterium tuberculosis. Protein J 2010; 28:281-93. [PMID: 19636684 DOI: 10.1007/s10930-009-9193-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Arylamine N-acetyltansferase (NAT) from Mycobacterium tuberculosis (TBNAT) is a potential drug target for anti-tubercular therapy. Recombinant TBNAT is much less soluble and is produced in lower yields than the closely related NAT from Mycobacterium marinum (MMNAT). In order to explore MMNAT as a model for TBNAT in drug discovery, we compare the two mycobacterial NAT enzymes. Two site-directed mutants of MMNAT have been prepared and characterised: MMNAT71, Tyr --> Phe and MMNAT209, Met --> Thr, in which residues within 6 A of the active-site cysteine have been replaced with the corresponding residue from TBNAT. Two chimeric proteins have also been produced in which the third domain of MMNAT has been replaced by the third domain of TBNAT and vice versa. The activity profile of the chimeric proteins suggests a role for the third domain in the evolutionary divergence of NAT between these closely related mycobacterial species.
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Affiliation(s)
- Elizabeth Fullam
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK
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Wang CJ, Laurieri N, Abuhammad A, Lowe E, Westwood I, Ryan A, Sim E. Role of tyrosine 131 in the active site of paAzoR1, an azoreductase with specificity for the inflammatory bowel disease prodrug balsalazide. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:2-7. [PMID: 20057057 PMCID: PMC2805523 DOI: 10.1107/s1744309109044741] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 10/27/2009] [Indexed: 11/10/2022]
Abstract
Azoreductase 1 from Pseudomonas aeruginosa strain PAO1 (paAzoR1) catalyses the activation of the prodrug balsalazide and reduces the azo dye methyl red using reduced nicotinamide adenine dinucleotide cofactor as an electron donor. To investigate the mechanism of the enzyme, a Y131F mutation was introduced and the enzymic properties of the mutant were compared with those of the wild-type enzyme. The crystallographic structure of the mutant with methyl red bound was solved at 2.1 A resolution and compared with the wild-type structure. Tyr131 is important in the architecture of the active site but is not essential for enzymic activity.
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Affiliation(s)
- Chan-Ju Wang
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
| | - Nicola Laurieri
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
| | - Areej Abuhammad
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
| | - Edward Lowe
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Park Road, Oxford OX1 3QU, England
| | - Isaac Westwood
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
| | - Ali Ryan
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
| | - Edith Sim
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England
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