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Li H, Hardy CD, Reidl CT, Jing Q, Xue F, Cinelli M, Silverman RB, Poulos TL. Crystallographic and Computational Insights into Isoform-Selective Dynamics in Nitric Oxide Synthase. Biochemistry 2024; 63:788-796. [PMID: 38417024 PMCID: PMC10956423 DOI: 10.1021/acs.biochem.3c00601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 03/01/2024]
Abstract
In our efforts to develop inhibitors selective for neuronal nitric oxide synthase (nNOS) over endothelial nitric oxide synthase (eNOS), we found that nNOS can undergo conformational changes in response to inhibitor binding that does not readily occur in eNOS. One change involves movement of a conserved tyrosine, which hydrogen bonds to one of the heme propionates, but in the presence of an inhibitor, changes conformation, enabling part of the inhibitor to hydrogen bond with the heme propionate. This movement does not occur as readily in eNOS and may account for the reason why these inhibitors bind more tightly to nNOS. A second structural change occurs upon the binding of a second inhibitor molecule to nNOS, displacing the pterin cofactor. Binding of this second site inhibitor requires structural changes at the dimer interface, which also occurs more readily in nNOS than in eNOS. Here, we used a combination of crystallography, mutagenesis, and computational methods to better understand the structural basis for these differences in NOS inhibitor binding. Computational results show that a conserved tyrosine near the primary inhibitor binding site is anchored more tightly in eNOS than in nNOS, allowing for less flexibility of this residue. We also find that the inefficiency of eNOS to bind a second inhibitor molecule is likely due to the tighter dimer interface in eNOS compared with nNOS. This study provides a better understanding of how subtle structural differences in NOS isoforms can result in substantial dynamic differences that can be exploited in the development of isoform-selective inhibitors.
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Affiliation(s)
- Huiying Li
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and
Chemistry, University of California, Irvine, California 92697-3900, United
States
| | - Christine D. Hardy
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and
Chemistry, University of California, Irvine, California 92697-3900, United
States
| | - Cory T. Reidl
- Department
of Chemistry, Department of Molecular Biosciences, Chemistry of Life
Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Qing Jing
- Department
of Chemistry, Department of Molecular Biosciences, Chemistry of Life
Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Fengtian Xue
- Department
of Chemistry, Department of Molecular Biosciences, Chemistry of Life
Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Maris Cinelli
- Department
of Chemistry, Department of Molecular Biosciences, Chemistry of Life
Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Richard B. Silverman
- Department
of Chemistry, Department of Molecular Biosciences, Chemistry of Life
Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
- Department
of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, United States
| | - Thomas L. Poulos
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and
Chemistry, University of California, Irvine, California 92697-3900, United
States
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2
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Vasu D, Do HT, Li H, Hardy CD, Awasthi A, Poulos TL, Silverman RB. Potent, Selective, and Membrane Permeable 2-Amino-4-Substituted Pyridine-Based Neuronal Nitric Oxide Synthase Inhibitors. J Med Chem 2023; 66:9934-9953. [PMID: 37433128 PMCID: PMC10824152 DOI: 10.1021/acs.jmedchem.3c00782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2023]
Abstract
A series of potent, selective, and highly permeable human neuronal nitric oxide synthase inhibitors (hnNOS), based on a difluorobenzene ring linked to a 2-aminopyridine scaffold with different functionalities at the 4-position, is reported. In our efforts to develop novel nNOS inhibitors for the treatment of neurodegenerative diseases, we discovered 17, which showed excellent potency toward both rat (Ki 15 nM) and human nNOS (Ki 19 nM), with 1075-fold selectivity over human eNOS and 115-fold selectivity over human iNOS. 17 also showed excellent permeability (Pe = 13.7 × 10-6 cm s-1), a low efflux ratio (ER 0.48), along with good metabolic stability in mouse and human liver microsomes, with half-lives of 29 and >60 min, respectively. X-ray cocrystal structures of inhibitors bound with three NOS enzymes, namely, rat nNOS, human nNOS, and human eNOS, revealed detailed structure-activity relationships for the observed potency, selectivity, and permeability properties of the inhibitors.
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Affiliation(s)
- Dhananjayan Vasu
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Ha T. Do
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Christine D. Hardy
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Amardeep Awasthi
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Thomas L. Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Richard B. Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, United States
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3
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Dong J, Li D, Kang L, Luo C, Wang J. Insights into human eNOS, nNOS and iNOS structures and medicinal indications from statistical analyses of their interactions with bound compounds. BIOPHYSICS REPORTS 2023; 9:159-175. [PMID: 38028152 PMCID: PMC10648232 DOI: 10.52601/bpr.2023.210045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 05/18/2023] [Indexed: 12/01/2023] Open
Abstract
83 Structures of human nNOS, 55 structures of human eNOS, 13 structures of iNOS, and about 126 reported NOS-bound compounds are summarized and analyzed. Structural and statistical analysis show that, at least one copy of each analyzed compound binds to the active site (the substrate arginine binding site) of human NOS. And binding features of the three isoforms show differences, but the binding preference of compounds is not in the way helpful for inhibitor design targeting nNOS and iNOS, or for activator design targeting eNOS. This research shows that there is a strong structural and functional similarity between oxygenase domains of human NOS isoforms, especially the architecture, residue composition, size, shape, and distribution profile of hydrophobicity, polarity and charge of the active site. The selectivity and efficacy of inhibitors over the rest of isoforms rely a lot on chance and randomness. Further increase of selectivity via rational improvement is uncertain, unpredictable and unreliable, therefore, to achieve high selectivity through targeting this site is complicated and requires combinative investigation. After analysis on the current two targeting sites in NOS, the highly conserved arginine binding pocket and H4B binding pocket, new potential drug-targeting sites are proposed based on structure and sequence profiling. This comprehensive analysis on the structure and interaction profiles of human NOS and bound compounds provides fresh insights for drug discovery and pharmacological research, and the new discovery here is practically applied to guide protein-structure based drug discovery.
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Affiliation(s)
- Jianshu Dong
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China
- Institute of Drug Discovery and Development, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Zhengzhou University, Zhengzhou 450001, China
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Henan Province, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Henan Province for Drug Quality control and Evaluation, Zhengzhou University, Zhengzhou 450001, China
| | - Dié Li
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China
- Institute of Drug Discovery and Development, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Zhengzhou University, Zhengzhou 450001, China
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Henan Province, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Henan Province for Drug Quality control and Evaluation, Zhengzhou University, Zhengzhou 450001, China
| | - Lei Kang
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China
- Institute of Drug Discovery and Development, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Zhengzhou University, Zhengzhou 450001, China
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Henan Province, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Henan Province for Drug Quality control and Evaluation, Zhengzhou University, Zhengzhou 450001, China
| | - Chenbing Luo
- School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou 450001, China
- Institute of Drug Discovery and Development, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China, Zhengzhou University, Zhengzhou 450001, China
- Collaborative Innovation Center of New Drug Research and Safety Evaluation, Henan Province, Zhengzhou University, Zhengzhou 450001, China
- Key Laboratory of Henan Province for Drug Quality control and Evaluation, Zhengzhou University, Zhengzhou 450001, China
| | - Jiangyun Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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Vasu D, Li H, Hardy CD, Poulos TL, Silverman RB. 2-Aminopyridines with a shortened amino sidechain as potent, selective, and highly permeable human neuronal nitric oxide synthase inhibitors. Bioorg Med Chem 2022; 69:116878. [PMID: 35772285 PMCID: PMC9574886 DOI: 10.1016/j.bmc.2022.116878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 11/21/2022]
Abstract
A series of potent, selective, and highly permeable human neuronal nitric oxide synthase inhibitors (hnNOS) based on the 2-aminopyridine scaffold with a shortened amino sidechain is reported. A rapid and simple protocol was developed to access these inhibitors in excellent yields. Neuronal nitric oxide synthase (nNOS) is a novel therapeutic target for the treatment of various neurological disorders. The major challenges in designing nNOS inhibitors in humans focus on potency, selectivity over other isoforms of nitric oxide synthases (NOSs), and blood-brain barrier permeability. In this context, we discovered a promising inhibitor, 6-(3-(4,4-difluoropiperidin-1-yl)propyl)-4-methylpyridin-2-amine dihydrochloride, that exhibits excellent potency for rat (Ki = 46 nM) and human nNOS (Ki = 48 nM), respectively, with 388-fold human eNOS and 135-fold human iNOS selectivity. It also displayed excellent permeability (Pe = 17.3 × 10-6 cm s-1) through a parallel artificial membrane permeability assay, a model for blood-brain permeability. We found that increasing lipophilicity by incorporation of fluorine atoms on the backbone of the inhibitors significantly increased potential blood-brain barrier permeability. In addition to measuring potency, isoform selectivity, and permeability of NOS inhibitors, we also explored structure-activity relationships via structures of key inhibitors complexed to various isoforms of nitric oxide synthases.
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Affiliation(s)
- Dhananjayan Vasu
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, CA 92697-3900, United States
| | - Christine D Hardy
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, CA 92697-3900, United States
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, CA 92697-3900, United States.
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Developmental Therapeutics, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, United States; Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States.
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5
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Doman AJ, Tommasi S, Perkins MV, McKinnon RA, Mangoni AA, Nair PC. Chemical similarities and differences among inhibitors of nitric oxide synthase, arginase and dimethylarginine dimethylaminohydrolase-1: implications for the design of novel enzyme inhibitors modulating the nitric oxide pathway. Bioorg Med Chem 2022; 72:116970. [DOI: 10.1016/j.bmc.2022.116970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 08/01/2022] [Accepted: 08/18/2022] [Indexed: 11/02/2022]
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6
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Kibou Z, Aissaoui N, Daoud I, Seijas JA, Vázquez-Tato MP, Klouche Khelil N, Choukchou-Braham N. Efficient Synthesis of 2-Aminopyridine Derivatives: Antibacterial Activity Assessment and Molecular Docking Studies. Molecules 2022; 27:3439. [PMID: 35684377 PMCID: PMC9182143 DOI: 10.3390/molecules27113439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/22/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022] Open
Abstract
A new and suitable multicomponent one-pot reaction was developed for the synthesis of 2-amino-3-cyanopyridine derivatives. BACKGROUND This synthesis was demonstrated by the efficient and easy access to a variety of substituted 2-aminopyridines using enaminones as key precursors under solvent-free conditions. METHODS A range of spectroscopic techniques was used to determine and confirm the chemical structures (FTIR, 1H NMR, 13C NMR). The antimicrobial potency of synthesized compounds (2a-d) was tested using disk diffusion assays, and the Minimum Inhibitory Concentration (MIC) for the active compounds was determined against a panel of microorganisms, including Gram-positive and Gram-negative bacteria and yeasts. Moreover, a docking analysis was conducted by Molecular Operating Environment (MOE) software to provide supplementary information about the potential, as well as an ADME-T prediction to describe the pharmacokinetic properties of the best compound and its toxicity. RESULTS The results of the antimicrobial activity indicated that compound 2c showed the highest activity against Gram-positive bacteria, particularly S. aureus and B. subtilis whose MIC values were 0.039 ± 0.000 µg·mL-1. The results of the theoretical study of compound 2c were in line with the experimental data and exhibited excellent antibacterial potential. CONCLUSIONS On the basis of the obtained results, compound 2c can be used as an antibacterial agent model with high antibacterial potency.
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Affiliation(s)
- Zahira Kibou
- Laboratoire de Catalyse et Synthèse en Chimie Organique, Faculté des Sciences, Université de Tlemcen, BP 119, Tlemcen 13000, Algeria;
- Faculté des Sciences et de la Technologie, Université de Ain Témouchent, BP 284, Ain Témouchent 46000, Algeria
| | - Nadia Aissaoui
- Laboratory of the Sustainable Management of Natural Resources in Arid and Semi Aridareas, University Center Salhi Ahmed Naama, BP 66, Naama 45000, Algeria;
- Department of Biology, Faculty of Nature and Life, Earth and Universe Sciences, University of Tlemcen, Tlemcen 13000, Algeria
| | - Ismail Daoud
- Département des Sciences de la Matière, Université de Mohamed Khider, BP 145 RP, Biskra 07000, Algerie;
- Laboratory of Natural and Bio-Active Substances, Faculty of Sciences, University of Tlemcen, BP 119, Tlemcen 13000, Algeria
| | - Julio A. Seijas
- Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Santiago de Compostela, A da, Alfonso X El Sabio s/n, 27002 Lugo, Spain;
| | - María Pilar Vázquez-Tato
- Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Santiago de Compostela, A da, Alfonso X El Sabio s/n, 27002 Lugo, Spain;
| | - Nihel Klouche Khelil
- Laboratory of Applied Microbiology in Food, Biomedical and Environment (LAMAABE), Department of Biology, Faculty of Nature and Life, Earth and Universe Sciences, University of Tlemcen, Tlemcen 13000, Algeria;
- Laboratory of Experimental Surgery, Medical Faculty, University of Tlemcen, Tlemcen 13000, Algeria
| | - Noureddine Choukchou-Braham
- Laboratoire de Catalyse et Synthèse en Chimie Organique, Faculté des Sciences, Université de Tlemcen, BP 119, Tlemcen 13000, Algeria;
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7
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Shcherbakov NV, Dar’in DV, Kukushkin VY, Dubovtsev AY. Hetero-Tetradehydro-Diels–Alder Cycloaddition of Enynamides and Cyanamides: Gold-Catalyzed Generation of Diversely Substituted 2,6-Diaminopyridines. J Org Chem 2021; 86:7218-7228. [DOI: 10.1021/acs.joc.1c00558] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Nikolay V. Shcherbakov
- Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034 Saint Petersburg, Russian Federation
| | - Dmitry V. Dar’in
- Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034 Saint Petersburg, Russian Federation
| | - Vadim Yu. Kukushkin
- Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034 Saint Petersburg, Russian Federation
- South Ural State University, 454080 Chelyabinsk, Russian Federation
| | - Alexey Yu. Dubovtsev
- Saint Petersburg State University, Universitetskaya Nab. 7/9, 199034 Saint Petersburg, Russian Federation
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8
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Tayab MA, Chowdhury KAA, Jabed M, Mohammed Tareq S, Kamal ATMM, Islam MN, Uddin AMK, Hossain MA, Emran TB, Simal-Gandara J. Antioxidant-Rich Woodfordia fruticosa Leaf Extract Alleviates Depressive-Like Behaviors and Impede Hyperglycemia. PLANTS (BASEL, SWITZERLAND) 2021; 10:287. [PMID: 33546288 PMCID: PMC7913287 DOI: 10.3390/plants10020287] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/12/2021] [Accepted: 01/26/2021] [Indexed: 12/19/2022]
Abstract
Dhaiphul (Woodfordia fruticosa) is a frequently demanded plant in South-East Asian regions for its diverse medicinal values. This study was proposed to examine antioxidant, antidiabetic, and antidepressant potentials of methanol extract of W. fruticosa leaves (MEWF) and its derived n-hexane (NHFMEWF) and ethyl acetate (EAFMEWF) fractions through in vitro, in vivo, and computational models. Among test samples, MEWF and EAFMEWF contained the highest phenolic content and showed maximal antioxidant activity in DPPH radical scavenging and ferric reducing power assays. In comparison, NHFMEWF possessed maximum flavonoid content and a significantly potent α-amylase inhibitory profile comparable with positive control acarbose. In animal models of depression (forced swimming and tail suspension test), EAFMEWF and NHFMEWF demonstrated a dose-dependent antidepressant-like effect; explicitly, the depressive-like behaviors significantly declined in EAFMEWF-treated dosing groups in contrast to the control group. In the computational analysis, previously isolated flavonoid compounds from Dhaiphul leaves manifested potent binding affinity against several key therapeutic target proteins of diabetes and depressive disorders including α-amylase, serotonin transporter, dopamine transporter, and neuronal nitric oxide synthase with varying pharmacokinetics and toxicity profiles. This research's outcomes may provide potential dietary supplements for mitigating hyperglycemia, cellular toxicity, and depressive disorder.
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Affiliation(s)
- Mohammed Abu Tayab
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Kazi Ashfak Ahmed Chowdhury
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Md. Jabed
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Syed Mohammed Tareq
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - A. T. M. Mostafa Kamal
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Mohammad Nazmul Islam
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - A. M. Kafil Uddin
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Mohammad Adil Hossain
- Department of Pharmacy, International Islamic University Chittagong, Chittagong 4318, Bangladesh; (M.A.T.); (K.A.A.C.); (M.J.); (S.M.T.); (A.T.M.M.K.); (A.M.K.U.); (M.A.H.)
| | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong 4381, Bangladesh
| | - Jesus Simal-Gandara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo—Ourense Campus, E32004 Ourense, Spain
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9
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DNA binding and cleavage studies of novel Betti base substituted quaternary Cu(II) and Zn(II) phthalocyanines. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114773] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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10
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Zi QX, Yan SJ, Yang CL, Li K, Lin J. Three-Component Cascade Reaction of 1,1-Enediamines, N, N-Dimethylformamide Dimethyl Acetal, and 1,3-Dicarbonyl Compounds: Selective Synthesis of Diverse 2-Aminopyridine Derivatives. ACS OMEGA 2019; 4:2863-2873. [PMID: 31459516 PMCID: PMC6648487 DOI: 10.1021/acsomega.8b03284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 01/25/2019] [Indexed: 06/10/2023]
Abstract
A novel approach has been developed for the synthesis of three kinds of highly functionalized 2-aminopyridine derivatives (APDs) through a three-component reaction of 1,1-enediamines (EDAMs) 1, N,N-dimethylformamide dimethyl acetal (DMF-DMA) 2, and 1,3-dicarbonyl compounds 3-5 via a base-promoted cascade reaction, producing the desired products in good to excellent yields. This method represents a route to obtain a novel class of APDs in a concise, rapid, and practical manner. This approach is particularly attractive because of the following features: low cost, mild temperature, atom economy, high yields, and potential biological activity of the product.
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Affiliation(s)
| | | | | | | | - Jun Lin
- E-mail: Phone/Fax: +86 87165031633 (J. L.)
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11
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Do HT, Li H, Chreifi G, Poulos TL, Silverman RB. Optimization of Blood-Brain Barrier Permeability with Potent and Selective Human Neuronal Nitric Oxide Synthase Inhibitors Having a 2-Aminopyridine Scaffold. J Med Chem 2019; 62:2690-2707. [PMID: 30802056 DOI: 10.1021/acs.jmedchem.8b02032] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Effective delivery of therapeutic drugs into the human brain is one of the most challenging tasks in central nervous system drug development because of the blood-brain barrier (BBB). To overcome the BBB, both passive permeability and efflux transporter liability of a compound must be addressed. Herein, we report our optimization related to BBB penetration of neuronal nitric oxide synthase (nNOS) inhibitors toward the development of new drugs for neurodegenerative diseases. Various approaches, including enhancing lipophilicity and rigidity of new inhibitors and modulating the p Ka of amino groups, have been employed. In addition to determining inhibitor potency and selectivity, crystal structures of most newly designed compounds complexed to various nitric oxide synthase isoforms have been determined. We have discovered a new analogue (21), which exhibits not only excellent potency ( Ki < 30 nM) in nNOS inhibition but also a significantly low P-glycoprotein and breast-cancer-resistant protein substrate liability as indicated by an efflux ratio of 0.8 in the Caco-2 bidirectional assay.
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Affiliation(s)
- Ha T Do
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208-3113 , United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry , University of California , Irvine , California 92697-3900 , United States
| | - Georges Chreifi
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry , University of California , Irvine , California 92697-3900 , United States
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry , University of California , Irvine , California 92697-3900 , United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208-3113 , United States
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12
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Do HT, Wang HY, Li H, Chreifi G, Poulos TL, Silverman RB. Improvement of Cell Permeability of Human Neuronal Nitric Oxide Synthase Inhibitors Using Potent and Selective 2-Aminopyridine-Based Scaffolds with a Fluorobenzene Linker. J Med Chem 2017; 60:9360-9375. [PMID: 29091437 DOI: 10.1021/acs.jmedchem.7b01356] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Inhibition of neuronal nitric oxide synthase (nNOS) is a promising therapeutic approach to treat neurodegenerative diseases. Recently, we have achieved considerable progress in improving the potency and isoform selectivity of human nNOS inhibitors bearing a 2-aminopyridine scaffold. However, these inhibitors still suffered from too low cell membrane permeability to enter into CNS drug development. We report herein our studies to improve permeability of nNOS inhibitors as measured by both PAMPA-BBB and Caco-2 assays. The most permeable compound (12) in this study still preserves excellent potency with human nNOS (Ki = 30 nM) and very high selectivity over other NOS isoforms, especially human eNOS (hnNOS/heNOS = 2799, the highest hnNOS/heNOS ratio we have obtained to date). X-ray crystallographic analysis reveals that 12 adopts a similar binding mode in both rat and human nNOS, in which the 2-aminopyridine and the fluorobenzene linker form crucial hydrogen bonds with glutamate and tyrosine residues, respectively.
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Affiliation(s)
- Ha T Do
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Heng-Yen Wang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine , Irvine California 92697-3900, United States
| | - Georges Chreifi
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine , Irvine California 92697-3900, United States
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine , Irvine California 92697-3900, United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Center for Developmental Therapeutics, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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13
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Pensa AV, Cinelli MA, Li H, Chreifi G, Mukherjee P, Roman LJ, Martásek P, Poulos TL, Silverman RB. Hydrophilic, Potent, and Selective 7-Substituted 2-Aminoquinolines as Improved Human Neuronal Nitric Oxide Synthase Inhibitors. J Med Chem 2017; 60:7146-7165. [PMID: 28776992 DOI: 10.1021/acs.jmedchem.7b00835] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neuronal nitric oxide synthase (nNOS) is a target for development of antineurodegenerative agents. Most nNOS inhibitors mimic l-arginine and have poor bioavailability. 2-Aminoquinolines showed promise as bioavailable nNOS inhibitors but suffered from low human nNOS inhibition, low selectivity versus human eNOS, and significant binding to other CNS targets. We aimed to improve human nNOS potency and selectivity and reduce off-target binding by (a) truncating the original scaffold or (b) introducing a hydrophilic group to interrupt the lipophilic, promiscuous pharmacophore and promote interaction with human nNOS-specific His342. We synthesized both truncated and polar 2-aminoquinoline derivatives and assayed them against recombinant NOS enzymes. Although aniline and pyridine derivatives interact with His342, benzonitriles conferred the best rat and human nNOS inhibition. Both introduction of a hydrophobic substituent next to the cyano group and aminoquinoline methylation considerably improved isoform selectivity. Most importantly, these modifications preserved Caco-2 permeability and reduced off-target CNS binding.
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Affiliation(s)
- Anthony V Pensa
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Maris A Cinelli
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Georges Chreifi
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Paramita Mukherjee
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Linda J Roman
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States
| | - Pavel Martásek
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States.,Department of Pediatrics and Center for Applied Genomics, First School of Medicine, Charles University and BIOCEV 121 08 Prague, Czech Republic
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , Evanston, Illinois 60208-3113, United States
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14
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Cinelli MA, Li H, Chreifi G, Poulos TL, Silverman RB. Nitrile in the Hole: Discovery of a Small Auxiliary Pocket in Neuronal Nitric Oxide Synthase Leading to the Development of Potent and Selective 2-Aminoquinoline Inhibitors. J Med Chem 2017; 60:3958-3978. [PMID: 28422508 PMCID: PMC5567828 DOI: 10.1021/acs.jmedchem.7b00259] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Neuronal nitric oxide synthase (nNOS) inhibition is a promising strategy to treat neurodegenerative disorders, but the development of nNOS inhibitors is often hindered by poor pharmacokinetics. We previously developed a class of membrane-permeable 2-aminoquinoline inhibitors and later rearranged the scaffold to decrease off-target binding. However, the resulting compounds had decreased permeability, low human nNOS activity, and low selectivity versus human eNOS. In this study, 5-substituted phenyl ether-linked aminoquinolines and derivatives were synthesized and assayed against purified NOS isoforms. 5-Cyano compounds are especially potent and selective rat and human nNOS inhibitors. Activity and selectivity are mediated by the binding of the cyano group to a new auxiliary pocket in nNOS. Potency was enhanced by methylation of the quinoline and by introduction of simple chiral moieties, resulting in a combination of hydrophobic and auxiliary pocket effects that yielded high (∼500-fold) n/e selectivity. Importantly, the Caco-2 assay also revealed improved membrane permeability over previous compounds.
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Affiliation(s)
- Maris A. Cinelli
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Georges Chreifi
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Thomas L. Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Richard B. Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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15
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Poulos TL, Li H. Nitric oxide synthase and structure-based inhibitor design. Nitric Oxide 2016; 63:68-77. [PMID: 27890696 DOI: 10.1016/j.niox.2016.11.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/09/2016] [Accepted: 11/21/2016] [Indexed: 11/24/2022]
Abstract
Once it was discovered that the enzyme nitric oxide synthase (NOS) is responsible for the biosynthesis of NO, NOS became a drug target. Particularly important is the over production of NO by neuronal NOS (nNOS) in various neurodegenerative disorders. After the various NOS isoforms were identified, inhibitor development proceeded rapidly. It soon became evident, however, that isoform selectivity presents a major challenge. All 3 human NOS isoforms, nNOS, eNOS (endothelial NOS), and iNOS (inducible NOS) have nearly identical active site structures thus making selective inhibitor design especially difficult. Of particular importance is the avoidance of inhibiting eNOS owing to its vital role in the cardiovascular system. This review summarizes some of the history of NOS inhibitor development and more recent advances in developing isoform selective inhibitors using primarily structure-based approaches.
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Affiliation(s)
- Thomas L Poulos
- Departments of Molecular Biology & Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, Irvine, CA 92697-3900, USA.
| | - Huiying Li
- Departments of Molecular Biology & Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, Irvine, CA 92697-3900, USA
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16
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Li H, Wang HY, Kang S, Silverman RB, Poulos TL. Electrostatic Control of Isoform Selective Inhibitor Binding in Nitric Oxide Synthase. Biochemistry 2016; 55:3702-7. [PMID: 27250740 DOI: 10.1021/acs.biochem.6b00261] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Development of potent and isoform selective nitric oxide synthase (NOS) inhibitors is challenging because of the structural similarity in the heme active sites. One amino acid difference between NOS isoforms, Asp597 in rat neuronal NOS (nNOS) versus Asn368 in bovine endothelial NOS (eNOS), has been identified as the structural basis for why some dipeptide amide inhibitors bind more tightly to nNOS than to eNOS. We now have found that the same amino acid variation is responsible for substantially different binding modes and affinity for a new class of aminopyridine-based inhibitors.
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Affiliation(s)
- Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Heng-Yen Wang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, and Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Soosung Kang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, and Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, and Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
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17
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Wang HY, Qin Y, Li H, Roman LJ, Martásek P, Poulos TL, Silverman RB. Potent and Selective Human Neuronal Nitric Oxide Synthase Inhibition by Optimization of the 2-Aminopyridine-Based Scaffold with a Pyridine Linker. J Med Chem 2016; 59:4913-25. [PMID: 27050842 DOI: 10.1021/acs.jmedchem.6b00273] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Neuronal nitric oxide synthase (nNOS) is an important therapeutic target for the treatment of various neurodegenerative disorders. A major challenge in the design of nNOS inhibitors focuses on potency in humans and selectivity over other NOS isoforms. Here we report potent and selective human nNOS inhibitors based on the 2-aminopyridine scaffold with a central pyridine linker. Compound 14j, the most promising inhibitor in this study, exhibits excellent potency for rat nNOS (Ki = 16 nM) with 828-fold n/e and 118-fold n/i selectivity with a Ki value of 13 nM against human nNOS with 1761-fold human n/e selectivity. Compound 14j also displayed good metabolic stability in human liver microsomes, low plasma protein binding, and minimal binding to cytochromes P450 (CYPs), although it had little to no Caco-2 permeability.
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Affiliation(s)
- Heng-Yen Wang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Yajuan Qin
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.,State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University , Nanjing 210093, People's Republic of China
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Linda J Roman
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States
| | - Pavel Martásek
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States.,Department of Pediatrics, First Faculty of Medicine, Charles University , 121 08 Prague, Czech Republic.,BIOCEV , 252 42 Vestec, Czech Republic
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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18
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Baral ER, Sharma K, Akhtar MS, Lee YR. A catalyst- and solvent-free thermal multicomponent approach for the construction of diverse and polysubstituted 2-aminopyridines and their antibacterial activity. Org Biomol Chem 2016; 14:10285-10297. [PMID: 27752699 DOI: 10.1039/c6ob02015a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A multicomponent approach for the synthesis of polysubstituted 2-aminopyridines under catalyst- and solvent-free thermal conditions has been established.
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Affiliation(s)
- Ek Raj Baral
- School of Chemical Engineering
- Yeungnam University
- Gyeongsan 712-749
- Republic of Korea
| | - Kavita Sharma
- School of Chemical Engineering
- Yeungnam University
- Gyeongsan 712-749
- Republic of Korea
| | | | - Yong Rok Lee
- School of Chemical Engineering
- Yeungnam University
- Gyeongsan 712-749
- Republic of Korea
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19
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Cinelli MA, Li H, Pensa AV, Kang S, Roman LJ, Martásek P, Poulos TL, Silverman RB. Phenyl Ether- and Aniline-Containing 2-Aminoquinolines as Potent and Selective Inhibitors of Neuronal Nitric Oxide Synthase. J Med Chem 2015; 58:8694-712. [PMID: 26469213 DOI: 10.1021/acs.jmedchem.5b01330] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Excess nitric oxide (NO) produced by neuronal nitric oxide synthase (nNOS) is implicated in neurodegenerative disorders. As a result, inhibition of nNOS and reduction of NO levels is desirable therapeutically, but many nNOS inhibitors are poorly bioavailable. Promising members of our previously reported 2-aminoquinoline class of nNOS inhibitors, although orally bioavailable and brain-penetrant, suffer from unfavorable off-target binding to other CNS receptors, and they resemble known promiscuous binders. Rearranged phenyl ether- and aniline-linked 2-aminoquinoline derivatives were therefore designed to (a) disrupt the promiscuous binding pharmacophore and diminish off-target interactions and (b) preserve potency, isoform selectivity, and cell permeability. A series of these compounds was synthesized and tested against purified nNOS, endothelial NOS (eNOS), and inducible NOS (iNOS) enzymes. One compound, 20, displayed high potency, selectivity, and good human nNOS inhibition, and retained some permeability in a Caco-2 assay. Most promisingly, CNS receptor counterscreening revealed that this rearranged scaffold significantly reduces off-target binding.
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Affiliation(s)
- Maris A Cinelli
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Huiying Li
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Anthony V Pensa
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Soosung Kang
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Linda J Roman
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States
| | - Pavel Martásek
- Department of Biochemistry, University of Texas Health Science Center , San Antonio, Texas 78384-7760, United States.,Department of Pediatrics, First Faculty of Medicine, Charles University , Prague, Czech Republic.,BIOCEV , Prague, Czech Republic
| | - Thomas L Poulos
- Departments of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California , Irvine, California 92697-3900, United States
| | - Richard B Silverman
- Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, Center for Molecular Innovation and Drug Discovery, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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20
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Holden JK, Dejam D, Lewis MC, Huang H, Kang S, Jing Q, Xue F, Silverman RB, Poulos TL. Inhibitor Bound Crystal Structures of Bacterial Nitric Oxide Synthase. Biochemistry 2015; 54:4075-82. [PMID: 26062720 DOI: 10.1021/acs.biochem.5b00431] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nitric oxide generated by bacterial nitric oxide synthase (NOS) increases the susceptibility of Gram-positive pathogens Staphylococcus aureus and Bacillus anthracis to oxidative stress, including antibiotic-induced oxidative stress. Not surprisingly, NOS inhibitors also improve the effectiveness of antimicrobials. Development of potent and selective bacterial NOS inhibitors is complicated by the high active site sequence and structural conservation shared with the mammalian NOS isoforms. To exploit bacterial NOS for the development of new therapeutics, recognition of alternative NOS surfaces and pharmacophores suitable for drug binding is required. Here, we report on a wide number of inhibitor-bound bacterial NOS crystal structures to identify several compounds that interact with surfaces unique to the bacterial NOS. Although binding studies indicate that these inhibitors weakly interact with the NOS active site, many of the inhibitors reported here provide a revised structural framework for the development of new antimicrobials that target bacterial NOS. In addition, mutagenesis studies reveal several key residues that unlock access to bacterial NOS surfaces that could provide the selectivity required to develop potent bacterial NOS inhibitors.
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Affiliation(s)
- Jeffrey K Holden
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Dillon Dejam
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew C Lewis
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - He Huang
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Soosung Kang
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Qing Jing
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Fengtian Xue
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Richard B Silverman
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Thomas L Poulos
- Departments of †Molecular Biology and Biochemistry, ‡Pharmaceutical Sciences, and §Chemistry, University of California, Irvine, California 92697-3900, United States.,∥Departments of Chemistry and Molecular Biosciences, ⊥Chemistry of Life Processes Institute, #Center for Molecular Innovation and Drug Discovery, Northwestern University, Evanston, Illinois 60208-3113, United States
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