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Wang Y, Ming XX, Zhang CP. Fluorine-Containing Inhalation Anesthetics: Chemistry, Properties and Pharmacology. Curr Med Chem 2020; 27:5599-5652. [DOI: 10.2174/0929867326666191003155703] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 08/27/2019] [Accepted: 09/05/2019] [Indexed: 02/07/2023]
Abstract
Studies on fluorinated inhalation anesthetics, including synthesis, physical chemistry and
pharmacology, have been summarized in this review. Retrospecting the history of inhalation anesthetics
revealed their increasing reliance on fluorine and ether structures. Halothane causes a rare but
severe immune-based hepatotoxicity, which was replaced by enflurane in the 1970s. Isoflurane replaced
enflurane in the 1980s, showing modest advantages (e.g. lower solubility, better metabolic
stability, and without convulsive predisposition). Desflurane and sevoflurane came into use in the
1990s, which are better anesthetics than isoflurane (less hepatotoxicity, lower solubility, and/or
markedly decreased pungency). However, they are still less than perfect. To gain more ideal inhalation
anesthetics, a large number of fluorinated halocarbons, polyfluorocycloalkanes, polyfluorocycloalkenes,
fluoroarenes, and polyfluorooxetanes, were prepared and their potency and toxicity were
evaluated. Although the pharmacology studies suggested that some of these agents produced anesthesia,
no further studies were continued on these compounds because they showed obvious lacking
as anesthetics. Moreover, the anesthetic activity cannot be simply predicted from the molecular
structures but has to be inferred from the experiments. Several regularities were found by experimental
studies: 1) the potency and toxicity of the saturated linear chain halogenated ether are enhanced
when its molecular weight is increased; 2) the margin of safety decreases and the recovery
time is prolonged when the boiling point of the candidate increases; and 3) compounds with an
asymmetric carbon terminal exhibit good anesthesia. Nevertheless, the development of new inhalation
anesthetics, better than desflurane and sevoflurane, is still challenging not only because of the
poor structure/activity relationship known so far but also due to synthetic issues.
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Affiliation(s)
- Yuzhong Wang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan 430079, China
| | - Xiao-Xia Ming
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, China
| | - Cheng-Pan Zhang
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, China
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2
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Kang C. 19F-NMR in Target-based Drug Discovery. Curr Med Chem 2019; 26:4964-4983. [PMID: 31187703 DOI: 10.2174/0929867326666190610160534] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 08/14/2018] [Accepted: 03/13/2019] [Indexed: 02/06/2023]
Abstract
Solution NMR spectroscopy plays important roles in understanding protein structures, dynamics and protein-protein/ligand interactions. In a target-based drug discovery project, NMR can serve an important function in hit identification and lead optimization. Fluorine is a valuable probe for evaluating protein conformational changes and protein-ligand interactions. Accumulated studies demonstrate that 19F-NMR can play important roles in fragment- based drug discovery (FBDD) and probing protein-ligand interactions. This review summarizes the application of 19F-NMR in understanding protein-ligand interactions and drug discovery. Several examples are included to show the roles of 19F-NMR in confirming identified hits/leads in the drug discovery process. In addition to identifying hits from fluorinecontaining compound libraries, 19F-NMR will play an important role in drug discovery by providing a fast and robust way in novel hit identification. This technique can be used for ranking compounds with different binding affinities and is particularly useful for screening competitive compounds when a reference ligand is available.
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Affiliation(s)
- CongBao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #05-01, Singapore, 138670, Singapore
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3
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Melikian M, Gramüller J, Hioe J, Greindl J, Gschwind RM. Brønsted acid catalysis - the effect of 3,3'-substituents on the structural space and the stabilization of imine/phosphoric acid complexes. Chem Sci 2019; 10:5226-5234. [PMID: 31191877 PMCID: PMC6540909 DOI: 10.1039/c9sc01044k] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/08/2019] [Indexed: 11/21/2022] Open
Abstract
BINOL derived chiral phosphoric acids (CPAs) are widely known for their high selectivity. Numerous 3,3'-substituents are used for a variety of stereoselective reactions and theoretical models of their effects are provided. However, experimental data about the structural space of CPA complexes in solution is extremely rare and so far restricted to NMR investigations of binary TRIP/imine complexes featuring two E- and two Z-imine conformations. Therefore, in this paper the structural space of 16 CPA/imine binary complexes is screened and 8 of them are investigated in detail by NMR. For the first time dimers of CPA/imine complexes in solution were experimentally identified, which show an imine position similar to the transition state in transfer hydrogenations. Furthermore, our experimental and computational data revealed an astonishing invariance of the four core structures regardless of the different steric and electronic properties of the 3,3'-substituent. However, a significant variation of E/Z-ratios is observed, demonstrating a strong influence of the 3,3'-substituents on the stabilization of the imine in the complexes. These experimental E/Z-ratios cannot be reproduced by calculations commonly applied for mechanistic studies, despite extensive conformational scans and treatment of the electronic structure at a high level of theory with various implicit solvent corrections. Thus, these first detailed experimental data about the structural space and influence of the 3,3'-substituent on the energetics of CPA/imine complexes can serve as basis to validate and improve theoretical predictive models.
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Affiliation(s)
- Maxime Melikian
- Institut für Organische Chemie , Universität Regensburg , D-93053 Regensburg , Germany .
| | - Johannes Gramüller
- Institut für Organische Chemie , Universität Regensburg , D-93053 Regensburg , Germany .
| | - Johnny Hioe
- Institut für Organische Chemie , Universität Regensburg , D-93053 Regensburg , Germany .
| | - Julian Greindl
- Institut für Organische Chemie , Universität Regensburg , D-93053 Regensburg , Germany .
| | - Ruth M Gschwind
- Institut für Organische Chemie , Universität Regensburg , D-93053 Regensburg , Germany .
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4
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Chaubey B, Pal S. Binding Interaction of Organofluorine–Serum Albumin: A Comparative Ligand-Detected 19F NMR Analysis. J Phys Chem B 2018; 122:9409-9418. [DOI: 10.1021/acs.jpcb.8b06583] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Bhawna Chaubey
- Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
| | - Samanwita Pal
- Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur 342037, India
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5
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Gajahi Soudahome A, Catan A, Giraud P, Assouan Kouao S, Guerin-Dubourg A, Debussche X, Le Moullec N, Bourdon E, Bravo SB, Paradela-Dobarro B, Álvarez E, Meilhac O, Rondeau P, Couprie J. Glycation of human serum albumin impairs binding to the glucagon-like peptide-1 analogue liraglutide. J Biol Chem 2018; 293:4778-4791. [PMID: 29414771 DOI: 10.1074/jbc.m117.815274] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 01/17/2018] [Indexed: 01/25/2023] Open
Abstract
The long-acting glucagon-like peptide-1 analogue liraglutide has proven efficiency in the management of type 2 diabetes and also has beneficial effects on cardiovascular diseases. Liraglutide's protracted action highly depends on its capacity to bind to albumin via its palmitic acid part. However, in diabetes, albumin can undergo glycation, resulting in impaired drug binding. Our objective in this study was to assess the impact of human serum albumin (HSA) glycation on liraglutide affinity. Using fluorine labeling of the drug and 19F NMR, we determined HSA affinity for liraglutide in two glycated albumin models. We either glycated HSA in vitro by incubation with glucose (G25- or G100-HSA) or methylglyoxal (MGO-HSA) or purified in vivo glycated HSA from the plasma of diabetic patients with poor glycemic control. Nonglycated commercial HSA (G0-HSA) and HSA purified from plasma of healthy individuals served as controls. We found that glycation decreases affinity for liraglutide by 7-fold for G100-HSA and by 5-fold for MGO-HSA compared with G0-HSA. A similarly reduced affinity was observed for HSA purified from diabetic individuals compared with HSA from healthy individuals. Our results reveal that glycation significantly impairs HSA affinity to liraglutide and confirm that glycation contributes to liraglutide's variable therapeutic efficiency, depending on diabetes stage. Because diabetes is a progressive disease, the effect of glycated albumin on liraglutide affinity found here is important to consider when diabetes is managed with this drug.
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Affiliation(s)
- Angélique Gajahi Soudahome
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France
| | - Aurélie Catan
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France
| | - Pierre Giraud
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France
| | - Sandrine Assouan Kouao
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France
| | - Alexis Guerin-Dubourg
- Services de Cardiologie et de Biologie, Centre Hospitalier Gabriel Martin, 97866 Saint-Paul, France
| | - Xavier Debussche
- Service d'Endocrinologie, Nutrition, et Diabétologie, CHU de La Réunion, 97400 Saint-Denis de La Réunion, France; CIC1410 INSERM, 97448 Saint-Pierre, Réunion, France
| | - Nathalie Le Moullec
- Service d'Endocrinologie, Nutrition, et Diabétologie, CHU de La Réunion, 97400 Saint-Denis de La Réunion, France; CIC1410 INSERM, 97448 Saint-Pierre, Réunion, France
| | - Emmanuel Bourdon
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France
| | - Susana B Bravo
- Proteomic Unit and Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), Hospital Clínico Universitario de Santiago, 15706 Santiago de Compostela, Spain; CIBERCV, Av. Monforte de Lemos, 3-5, Pabellón 11, Planta 0 28029 Madrid, Spain
| | - Beatriz Paradela-Dobarro
- Proteomic Unit and Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), Hospital Clínico Universitario de Santiago, 15706 Santiago de Compostela, Spain; CIBERCV, Av. Monforte de Lemos, 3-5, Pabellón 11, Planta 0 28029 Madrid, Spain
| | - Ezequiel Álvarez
- Proteomic Unit and Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), Hospital Clínico Universitario de Santiago, 15706 Santiago de Compostela, Spain; CIBERCV, Av. Monforte de Lemos, 3-5, Pabellón 11, Planta 0 28029 Madrid, Spain
| | - Olivier Meilhac
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France; Centre d'Investigation Clinique, CHU de La Réunion, 97448 Saint-Pierre, Réunion, France
| | - Philippe Rondeau
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France.
| | - Joël Couprie
- Université de La Réunion, INSERM, UMR 1188 Diabète Athérothrombose Thérapie Réunion Océan Indien (DéTROI), 97490 Saint-Denis de La Réunion, France.
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6
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Sakuma C, Kurita JI, Furihata K, Tashiro M. Achievement of 1 H-19 F heteronuclear experiments using the conventional spectrometer with a shared single high band amplifier. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:327-329. [PMID: 25808615 DOI: 10.1002/mrc.4210] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/09/2014] [Accepted: 12/15/2014] [Indexed: 06/04/2023]
Abstract
The (1)H-(19) F heteronuclear NMR experiments were achieved using the conventional spectrometer equipped with a single high band amplifier and a (1)H/(19)F/(13) C double-tuned probe. Although double high band amplifiers are generally required to perform such experiments, a simple modification of pathway in the conventional spectrometer was capable of acquiring various (1)H-(19)F heteronuclear spectra. The efficiency of the present technique was demonstrated in an application for (19)F{(1)H} and (1)H{(19)F} saturation transfer difference experiments.
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Affiliation(s)
- Chiseko Sakuma
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Horinouchi, Hachioji, Tokyo, 192-0392, Japan
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7
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Zhuang J, Yang DP, Nikas SP, Zhao J, Guo J, Makriyannis A. The interaction of fatty acid amide hydrolase (FAAH) inhibitors with an anandamide carrier protein using (19)F-NMR. AAPS JOURNAL 2013; 15:477-82. [PMID: 23344792 DOI: 10.1208/s12248-013-9455-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 01/09/2013] [Indexed: 12/20/2022]
Abstract
It has been reported that the endocannabinoid anandamide (AEA) binds to a class of fatty acid-binding proteins and serum albumin which can serve as carrier proteins and potentiate the cellular uptake of AEA and its intracellular translocation. Here, we employed (19)F nuclear magnetic resonance spectroscopy to study the interactions of serum albumin with two inhibitors of fatty acid amide hydrolase (FAAH), the enzyme involved in the deactivation of anandamide. We found that, for both inhibitors AM5206 and AM5207, the primary binding site on serum albumin is drug site 1 located at subdomain IIA. Neither inhibitor binds to drug site 2. While AM5207 binds exclusively to drug site 1, AM5206 also interacts with other fatty acid-binding sites on serum albumin. Additionally, AM5206 has an affinity for serum albumin approximately one order of magnitude higher than that of AM5207. The data suggest that interactions of FAAH inhibitors with albumin may provide added advantages for their ability to modulate endocannabinoid levels for a range of applications including analgesia, antiemesis, and neuroprotection.
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Affiliation(s)
- Jianqin Zhuang
- Center for Drug Discovery, Department of Pharmaceutical Sciences, and Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
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8
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Song Z, Zhao H, Olubajo O, Hall LB, Orr CN, Askew CB. Characterizing the binding of nucleotide ATP on serum albumin by 31P NMR diffusion. CAN J CHEM 2012. [DOI: 10.1139/v2012-011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pulsed-field-gradient (PFG) 31P NMR diffusion spectra were measured under varied sample conditions to characterize the low-affinity binding of adenosine 5′-triphosphate (ATP) on human serum albumin (HSA) or bovine serum albumin (BSA). The NMR diffusion constants of ATP, ATP–HSA, or ATP–BSA were illustrated as function of ATP concentrations. The binding curves of ATP–HSA and ATP–BSA were identical but strikingly different from the ATP curve. Using a “Scatchard plot”, the apparent binding constant (K) and number of ATP binding sites (n) on serum albumin were evaluated as K = 75.25 (mol/L)–1 and n = 10, respectively. At a pH < 5.0 and a pH > 9.0 or a temperature > 45 °C, the diffusion data of ATP–HSA were found to increase remarkably, suggesting that the dissociation of ATP from HSA was largely enhanced, probably because of pH- or heat-induced protein structural change, degradation, or aggregation. In addition, our data indicated that ADP was strongly competitive with ATP for the low-affinity binding to HSA, but heptanone and Cl– were essentially noncompetitive. These results are important for further elucidating the interaction of ATP with serum albumin and its possible effect on related bioprocesses. The method can be well applied to study the binding of other nucleotides/nucleosides on proteins.
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Affiliation(s)
- Zhiyan Song
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
| | - Hua Zhao
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
| | - Olarongbe Olubajo
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
| | - Lewis B. Hall
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
| | - Chauncey N. Orr
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
| | - Courtney B. Askew
- Department of Natural Sciences, Savannah State University, Savannah, GA 31404, USA
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9
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Subbotina JO, Johannes J, Lev B, Noskov SY. Halothane solvation in water and organic solvents from molecular simulations with new polarizable potential function. J Phys Chem B 2010; 114:6401-8. [PMID: 20411978 DOI: 10.1021/jp908339j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The partitioning of a substrate from one phase into another is a complex process with widespread applications: from chemical technology to the pharmaceutical industry. One particularly well-known and well-studied example is 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) trafficking through the lipid bilayer. Halothane is a model volatile anesthetic known to impact functions of model lipid bilayers, altering the structure and thickness upon its partitioning from the bulk phase. A number of theoretical and experimental investigations suggest the importance of electronic polarizability, determining a preference for halothane to partition in the interfacial systems as in lipid bilayers or binary solvents. The recently published protocol for the development of polarizable force fields based on the classical Drude model has provided fresh impetus to efforts directed at understanding the molecular principles governing complex thermodynamics of the hydrophobic hydration. Here, molecular simulations were combined with free energy simulations to study solvation of halothane in polarizable water and methanol. The absolute free energy of halothane solvation in different solvents (water, methanol, and n-hexane) has been evaluated for additive and polarizable models. It was found that both additive and polarizable models provide an adequate description of the halothane solvation in high-dielectric (polar) solvents such as water, but explicit accounting for electronic polarization is imperative for a correct description of the solvation thermodynamics in nonpolar systems. To study halothane dynamics in binary mixtures, all-atom molecular dynamics (MD) simulations for halothane-methanol mixtures in a wide range of concentrations were performed alongside an analysis of structural organization, dynamics, and thermodynamic properties to dissect the molecular determinants of the halothane solvation in polar and amphiphilic liquids such as methanol. Additionally, a theoretical test of the hypothesis on the weak hydrogen bonding of halothane and methanol in the condensed phase is provided, which was presented on the basis of spectroscopic analysis of the C-H vibrations in different gas-phase complexes. The simulations performed in the condensed phase suggest that hydrophobic interactions between halothane and methanol play a dominant role in preferential solvation.
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Affiliation(s)
- Julia O Subbotina
- Institute for BioComplexity and Informatics and Department for Biological Sciences, University of Calgary, 2500 University Drive, Calgary, AB, Canada T2N 1N4
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Streiff JH, Jones KA. Volatile anesthetic binding to proteins is influenced by solvent and aliphatic residues. J Chem Inf Model 2008; 48:2066-73. [PMID: 18808106 DOI: 10.1021/ci800206a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The main objective of this work was to characterize VA binding sites in multiple anesthetic target proteins. A computational algorithm was used to quantify the solvent exclusion and aliphatic character of amphiphilic pockets in the structures of VA binding proteins. VA binding sites in the protein structures were defined as the pockets with solvent exclusion and aliphatic character that exceeded minimum values observed in the VA binding sites of serum albumin, firefly luciferase, and apoferritin. We found that the structures of VA binding proteins are enriched in these pockets and that the predicted binding sites were consistent with experimental determined binding locations in several proteins. Autodock3 was used to dock the simulated molecules of 1,1,1,2,2-pentafluoroethane, difluoromethyl 1,1,1,2-tetrafluoroethyl ether, and sevoflurane and the isomers of halothane and isoflurane into these potential binding sites. We found that the binding of the various VA molecules to the amphiphilic pockets is driven primarily by VDW interactions and to a lesser extent by weak hydrogen bonding and electrostatic interactions. In addition, the trend in Delta G binding values follows the Meyer-Overton rule. These results suggest that VA potencies are related to the VDW interactions between the VA ligand and protein target. It is likely that VA bind to sites with a high degree of solvent exclusion and aliphatic character because aliphatic residues provide favorable VDW contacts and weak hydrogen bond donors. Water molecules occupying these sites maintain pocket integrity, associate with the VA ligand, and diminish the unfavorable solvation enthalpy of the VA. Water molecules displaced into the bulk by the VA ligand may provide an additional favorable enthalpic contribution to VA binding. Anesthesia is a component of many health related procedures, the outcomes of which could be improved with a better understanding of the molecular targets and mechanisms of anesthetic action.
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Affiliation(s)
- John H Streiff
- Department of Anesthesiology, University of Alabama at Birmingham, 901 19th Street South, Birmingham, AL 35294-1150, USA.
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11
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Williams DE, Peters MB, Wang B, Merz KM. MNDO parameters for the prediction of 19F NMR chemical shifts in biologically relevant compounds. J Phys Chem A 2008; 112:8829-38. [PMID: 18722416 DOI: 10.1021/jp801649f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The semiempirical MNDO methodology for qualitative description NMR chemical shifts has now been extended with the addition of NMR-specific parameters for the fluorine atom. This approach can be employed using semiempirical (AM1/PM3) geometries with good accuracy and can be executed at a fraction of the cost of ab initio and DFT methods, providing an attractive option for the computational studies of (19)F NMR for much larger systems. The data set used in the parametrization is large and diverse and specifically geared toward biologically relevant compounds. The new parameters are applicable to fluorine atoms involved in carbon-fluorine bonds. These parameters yield results comparable to NMR calculations performed at the DFT (B3LYP) level using the 6-31++G(d,p) basis set. The average R (2) and rms error for this data set is 0.94 and 13.85 ppm, respectively, compared to 0.96 and 10.45 ppm when DFT methods are used.
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Affiliation(s)
- Duane E Williams
- Department of Chemistry and Quantum Theory Project, 2328 New Physics Building, P.O. Box 118435, University of Florida, Gainesville, Florida 32611-8435, USA
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12
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Streiff JH, Allen TW, Atanasova E, Juranic N, Macura S, Penheiter AR, Jones KA. Prediction of volatile anesthetic binding sites in proteins. Biophys J 2006; 91:3405-14. [PMID: 16877516 PMCID: PMC1614498 DOI: 10.1529/biophysj.106.082586] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Computational methods designed to predict and visualize ligand protein binding interactions were used to characterize volatile anesthetic (VA) binding sites and unoccupied pockets within the known structures of VAs bound to serum albumin, luciferase, and apoferritin. We found that both the number of protein atoms and methyl hydrogen, which are within approximately 8 A of a potential ligand binding site, are significantly greater in protein pockets where VAs bind. This computational approach was applied to structures of calmodulin (CaM), which have not been determined in complex with a VA. It predicted that VAs bind to [Ca(2+)](4)-CaM, but not to apo-CaM, which we confirmed with isothermal titration calorimetry. The VA binding sites predicted for the structures of [Ca(2+)](4)-CaM are located in hydrophobic pockets that form when the Ca(2+) binding sites in CaM are saturated. The binding of VAs to these hydrophobic pockets is supported by evidence that halothane predominantly makes contact with aliphatic resonances in [Ca(2+)](4)-CaM (nuclear Overhauser effect) and increases the Ca(2+) affinity of CaM (fluorescence spectroscopy). Our computational analysis and experiments indicate that binding of VA to proteins is consistent with the hydrophobic effect and the Meyer-Overton rule.
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Affiliation(s)
- John H Streiff
- Departments of Anesthesiology and Molecular Pharmacology and Experimental Therapeutics and Biochemistry and Molecular Biology, Mayo College of Medicine, Rochester, Minnesota, USA.
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Yu L, Hajduk PJ, Mack J, Olejniczak ET. Structural studies of Bcl-xL/ligand complexes using 19F NMR. JOURNAL OF BIOMOLECULAR NMR 2006; 34:221-7. [PMID: 16645812 DOI: 10.1007/s10858-006-0005-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Accepted: 01/11/2006] [Indexed: 05/08/2023]
Abstract
Fluorine atoms are often incorporated into drug molecules as part of the lead optimization process in order to improve affinity or modify undesirable metabolic and pharmacokinetic profiles. From an NMR perspective, the abundance of fluorinated drug leads provides an exploitable niche for structural studies using 19F NMR in the drug discovery process. As 19F has no interfering background signal from biological sources, 19F NMR studies of fluorinated drugs bound to their protein receptors can yield easily interpretable and unambiguous structural constraints. 19F can also be selectively incorporated into proteins to obtain additional constraints for structural studies. Despite these advantages, 19F NMR has rarely been exploited for structural studies due to its broad lines in macromolecules and their ligand complexes, leading to weak signals in 1H/19F heteronuclear NOE experiments. Here we demonstrate several different experimental strategies that use 19F NMR to obtain ligand-protein structural constraints for ligands bound to the anti-apoptotic protein Bcl-xL, a drug target for anti-cancer therapy. These examples indicate the applicability of these methods to typical structural problems encountered in the drug development process.
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Affiliation(s)
- Liping Yu
- Pharmaceutical Discovery Division, GPRD, Abbott Laboratories, Abbott Park, IL 60064-6098, USA
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