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Jacobi T, Kratzer DA, Plapp BV. Substitution of both histidines in the active site of yeast alcohol dehydrogenase 1 exposes underlying pH dependencies. Chem Biol Interact 2024; 394:110992. [PMID: 38579923 PMCID: PMC11090211 DOI: 10.1016/j.cbi.2024.110992] [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: 01/26/2024] [Revised: 03/13/2024] [Accepted: 04/02/2024] [Indexed: 04/07/2024]
Abstract
Histidine residues 44 and 48 in yeast alcohol dehydrogenase (ADH) bind to the coenzymes NAD(H) and contribute to catalysis. The individual H44R and H48Q substitutions alter the kinetics and pH dependencies, and now the roles of other ionizable groups in the enzyme were studied in the doubly substituted H44R/H48Q ADH. The substitutions make the enzyme more resistant to inactivation by diethyl pyrocarbonate, modestly improve affinity for coenzymes, and substantially decrease catalytic efficiencies for ethanol oxidation and acetaldehyde reduction. The pH dependencies for several kinetic parameters are shifted from pK values for wild-type ADH of 7.3-8.1 to values for H44R/H48Q ADH of 8.0-9.6, and are assigned to the water or alcohol bound to the catalytic zinc. It appears that the rate of binding of NAD+ is electrostatically favored with zinc-hydroxide whereas binding of NADH is faster with neutral zinc-water. The pH dependencies of catalytic efficiencies (V/EtKm) for ethanol oxidation and acetaldehyde reduction are similarly controlled by deprotonation and protonation, respectively. The substitutions make an enzyme that resembles the homologous horse liver H51Q ADH, which has Arg-47 and Gln-51 and exhibits similar pK values. In the wild-type ADHs, it appears that His-48 (or His-51) in the proton relay systems linked to the catalytic zinc ligands modulate catalytic efficiencies.
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Affiliation(s)
- Tobias Jacobi
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Darla Ann Kratzer
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA.
| | - Bryce V Plapp
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA.
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2
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Ngo HPT, Nguyen DQ, Park H, Park YS, Kwak K, Kim T, Lee JH, Cho KS, Kang LW. Conformational change of organic cofactor PLP is essential for catalysis in PLP-dependent enzymes. BMB Rep 2022; 55:439-446. [PMID: 36104257 PMCID: PMC9537024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/21/2022] [Accepted: 07/11/2022] [Indexed: 03/08/2024] Open
Abstract
Pyridoxal 5'-phosphate (PLP)-dependent enzymes are ubiquitous, catalyzing various biochemical reactions of approximately 4% of all classified enzymatic activities. They transform amines and amino acids into important metabolites or signaling molecules and are important drug targets in many diseases. In the crystal structures of PLP-dependent enzymes, organic cofactor PLP showed diverse conformations depending on the catalytic step. The conformational change of PLP is essential in the catalytic mechanism. In the study, we review the sophisticated catalytic mechanism of PLP, especially in transaldimination reactions. Most drugs targeting PLP-dependent enzymes make a covalent bond to PLP with the transaldimination reaction. A detailed understanding of organic cofactor PLP will help develop a new drug against PLP-dependent enzymes. [BMB Reports 2022; 55(9): 439-446].
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Affiliation(s)
- Ho-Phuong-Thuy Ngo
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Diem Quynh Nguyen
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Hyunjae Park
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Yoon Sik Park
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Kiwoong Kwak
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Taejoon Kim
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Jang Ho Lee
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Kyoung Sang Cho
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
| | - Lin-Woo Kang
- Department of Biological Sciences, Konkuk University, Seoul 05029, Korea
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3
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Plapp BV, Subramanian R. Alternative binding modes in abortive NADH-alcohol complexes of horse liver alcohol dehydrogenase. Arch Biochem Biophys 2021; 701:108825. [PMID: 33675814 PMCID: PMC7980771 DOI: 10.1016/j.abb.2021.108825] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/24/2021] [Accepted: 02/25/2021] [Indexed: 10/22/2022]
Abstract
Enzymes typically have high specificity for their substrates, but the structures of substrates and products differ, and multiple modes of binding are observed. In this study, high resolution X-ray crystallography of complexes with NADH and alcohols show alternative modes of binding in the active site. Enzyme crystallized with the good substrates NAD+ and 4-methylbenzyl alcohol was found to be an abortive complex of NADH with 4-methylbenzyl alcohol rotated to a "non-productive" mode as compared to the structures that resemble reactive Michaelis complexes with NAD+ and 2,2,2-trifluoroethanol or 2,3,4,5,6-pentafluorobenzyl alcohol. The NADH is formed by reduction of the NAD+ with the alcohol during the crystallization. The same structure was also formed by directly crystallizing the enzyme with NADH and 4-methylbenzyl alcohol. Crystals prepared with NAD+ and 4-bromobenzyl alcohol also form the abortive complex with NADH. Surprisingly, crystals prepared with NAD+ and the strong inhibitor 1H,1H-heptafluorobutanol also had NADH, and the alcohol was bound in two different conformations that illustrate binding flexibility. Oxidation of 2-methyl-2,4-pentanediol during the crystallization apparently led to reduction of the NAD+. Kinetic studies show that high concentrations of alcohols can bind to the enzyme-NADH complex and activate or inhibit the enzyme. Together with previous studies on complexes with NADH and formamide analogues of the carbonyl substrates, models for the Michaelis complexes with NAD+-alcohol and NADH-aldehyde are proposed.
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Affiliation(s)
- Bryce V Plapp
- Department of Biochemistry, The University of Iowa, Iowa City, IA, 52242, USA.
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4
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Guntupalli SR, Li Z, Chang L, Plapp BV, Subramanian R. Cryo-Electron Microscopy Structures of Yeast Alcohol Dehydrogenase. Biochemistry 2021; 60:663-677. [PMID: 33620215 DOI: 10.1021/acs.biochem.0c00921] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Structures of yeast alcohol dehydrogenase determined by X-ray crystallography show that the subunits have two different conformational states in each of the two dimers that form the tetramer. Apoenzyme and holoenzyme complexes relevant to the catalytic mechanism were described, but the asymmetry led to questions about the cooperativity of the subunits in catalysis. This study used cryo-electron microscopy (cryo-EM) to provide structures for the apoenzyme, two different binary complexes with NADH, and a ternary complex with NAD+ and 2,2,2-trifluoroethanol. All four subunits in each of these complexes are identical, as the tetramers have D2 symmetry, suggesting that there is no preexisting asymmetry and that the subunits can be independently active. The apoenzyme and one enzyme-NADH complex have "open" conformations and the inverted coordination of the catalytic zinc with Cys-43, His-66, Glu-67, and Cys-153, whereas another enzyme-NADH complex and the ternary complex have closed conformations with the classical coordination of the zinc with Cys-43, His-66, Cys-153, and a water or the oxygen of trifluoroethanol. The conformational change involves interactions of Arg-340 with the pyrophosphate group of the coenzyme and Glu-67. The cryo-EM and X-ray crystallography studies provide structures relevant for the catalytic mechanism.
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Affiliation(s)
- Sai Rohit Guntupalli
- Institute for Stem Cell Science and Regenerative Medicine, Bangalore, India.,Manipal University, Manipal, India.,Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, United States
| | - Zhuang Li
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, United States
| | - Leifu Chang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, United States
| | - Bryce V Plapp
- Department of Biochemistry, Bowen Science Building, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Ramaswamy Subramanian
- Department of Biological Sciences and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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5
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Di L, Balesano A, Jordan S, Shi SM. The Role of Alcohol Dehydrogenase in Drug Metabolism: Beyond Ethanol Oxidation. AAPS JOURNAL 2021; 23:20. [DOI: 10.1208/s12248-020-00536-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/17/2020] [Indexed: 02/08/2023]
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6
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Kim K, Plapp BV. Substitutions of Amino Acid Residues in the Substrate Binding Site of Horse Liver Alcohol Dehydrogenase Have Small Effects on the Structures but Significantly Affect Catalysis of Hydrogen Transfer. Biochemistry 2020; 59:862-879. [PMID: 31994873 DOI: 10.1021/acs.biochem.9b01074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Previous studies showed that the L57F and F93W alcohol dehydrogenases catalyze the oxidation of benzyl alcohol with some quantum mechanical hydrogen tunneling, whereas the V203A enzyme has diminished tunneling. Here, steady-state kinetics for the L57F and F93W enzymes were studied, and microscopic rate constants for the ordered bi-bi mechanism were estimated from simulations of transient kinetics for the S48T, F93A, S48T/F93A, F93W, and L57F enzymes. Catalytic efficiencies for benzyl alcohol oxidation (V1/EtKb) vary over a range of ∼100-fold for the less active enzymes up to the L57F enzyme and are mostly associated with the binding of alcohol rather than the rate constants for hydride transfer. In contrast, catalytic efficiencies for benzaldehyde reduction (V2/EtKp) are ∼500-fold higher for the L57F enzyme than for the less active enzymes and are mostly associated with the rate constants for hydride transfer. Atomic-resolution structures (1.1 Å) for the F93W and L57F enzymes complexed with NAD+ and 2,3,4,5,6-pentafluorobenzyl alcohol or 2,2,2-trifluoroethanol are almost identical to previous structures for the wild-type, S48T, and V203A enzymes. Least-squares refinement with SHELXL shows that the nicotinamide ring is slightly strained in all complexes and that the apparent donor-acceptor distances from C4N of NAD to C7 of pentafluorobenzyl alcohol range from 3.28 to 3.49 Å (±0.02 Å) and are not correlated with the rate constants for hydride transfer or hydrogen tunneling. How the substitutions affect the dynamics of reorganization during hydrogen transfer and the extent of tunneling remain to be determined.
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Affiliation(s)
- Keehyuk Kim
- Department of Biochemistry , The University of Iowa , Iowa City , Iowa 52242 , United States
| | - Bryce V Plapp
- Department of Biochemistry , The University of Iowa , Iowa City , Iowa 52242 , United States
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7
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Plapp BV, Savarimuthu BR, Ferraro DJ, Rubach JK, Brown EN, Ramaswamy S. Horse Liver Alcohol Dehydrogenase: Zinc Coordination and Catalysis. Biochemistry 2017. [PMID: 28640600 PMCID: PMC5518280 DOI: 10.1021/acs.biochem.7b00446] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
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During catalysis
by liver alcohol dehydrogenase (ADH), a water
bound to the catalytic zinc is replaced by the oxygen of the substrates.
The mechanism might involve a pentacoordinated zinc or a double-displacement
reaction with participation by a nearby glutamate residue, as suggested
by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs.
Zinc coordination and participation of water in the enzyme mechanism
were investigated by X-ray crystallography. The apoenzyme and its
complex with adenosine 5′-diphosphoribose have an open protein
conformation with the catalytic zinc in one position, tetracoordinated
by Cys-46, His-67, Cys-174, and a water molecule. The bidentate chelators
2,2′-bipyridine and 1,10-phenanthroline displace the water
and form a pentacoordinated zinc. The enzyme–NADH complex has
a closed conformation similar to that of ternary complexes with coenzyme
and substrate analogues; the coordination of the catalytic zinc is
similar to that found in the apoenzyme, except that a minor, alternative
position for the catalytic zinc is ∼1.3 Å from the major
position and closer to Glu-68, which could form the alternative coordination
to the catalytic zinc. Complexes with NADH and N-1-methylhexylformamide
or N-benzylformamide (or with NAD+ and
fluoro alcohols) have the classical tetracoordinated zinc, and no
water is bound to the zinc or the nicotinamide rings. The major forms
of the enzyme in the mechanism have a tetracoordinated zinc, where
the carboxylate group of Glu-68 could participate in the exchange
of water and substrates on the zinc. Hydride transfer in the Michaelis
complexes does not involve a nearby water.
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Affiliation(s)
- Bryce V Plapp
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Baskar Raj Savarimuthu
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Daniel J Ferraro
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Jon K Rubach
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - Eric N Brown
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
| | - S Ramaswamy
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States
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8
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Sachse B, Meinl W, Glatt H, Monien BH. Ethanol and 4-methylpyrazole increase DNA adduct formation of furfuryl alcohol in FVB/N wild-type mice and in mice expressing human sulfotransferases 1A1/1A2. Carcinogenesis 2016; 37:314-319. [PMID: 26775039 DOI: 10.1093/carcin/bgw006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/08/2016] [Indexed: 11/13/2022] Open
Abstract
Furfuryl alcohol (FFA) is a carcinogenic food contaminant, which is formed by acid- and heat-catalyzed degradation of fructose and glucose. The activation by sulfotransferases (SULTs) yields a DNA reactive and mutagenic sulfate ester. The most prominent DNA adduct, N(2)-((furan-2-yl)methyl)-2'-deoxyguanosine (N(2)-MF-dG), was detected in FFA-treated mice and also in human tissue samples. The dominant pathway of FFA detoxification is the oxidation via alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs). The activity of these enzymes may be greatly altered in the presence of inhibitors or competitive substrates. Here, we investigated the impact of ethanol and the ADH inhibitor 4-methylpyrazole (4MP) on the DNA adduct formation by FFA in wild-type and in humanized mice that were transgenic for human SULT1A1/1A2 and deficient in the mouse (m) Sult1a1 and Sult1d1 genes (h1A1/1A2/1a1(-)/1d1(-)). The administration of FFA alone led to hepatic adduct levels of 4.5 N(2)-MF-dG/10(8) nucleosides and 33.6 N(2)-MF-dG/10(8) nucleosides in male and female wild-type mice, respectively, and of 19.6 N(2)-MF-dG/10(8) nucleosides and 95.4 N(2)-MF-dG/10(8) nucleosides in male and female h1A1/1A2/1a1(-)/1d1(-) mice. The coadministration of 1.6g ethanol/kg body weight increased N(2)-MF-dG levels by 2.3-fold in male and by 1.7-fold in female wild-type mice and by 2.5-fold in male and by 1.5-fold in female h1A1/1A2/1a1(-)/1d1(-) mice. The coadministration of 100mg 4MP/kg body weight had a similar effect on the adduct levels. These findings indicate that modulators of the oxidative metabolism, e.g. the drug 4MP or consumption of alcoholic beverages, may increase the genotoxic effects of FFA also in humans.
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Affiliation(s)
- Benjamin Sachse
- Research Group Genotoxic Food Contaminants.,Department of Molecular Toxicology and
| | - Walter Meinl
- Department of Molecular Toxicology and.,Department of Nutritional Toxicology, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, 14558 Nuthetal, Germany and
| | - Hansruedi Glatt
- Department of Nutritional Toxicology, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, 14558 Nuthetal, Germany and.,Department of Food Safety, Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589 Berlin, Germany
| | - Bernhard H Monien
- Research Group Genotoxic Food Contaminants.,Department of Food Safety, Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589 Berlin, Germany
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9
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Jadhav SB, Bankar SB, Granström T, Ojamo H, Singhal RS, Survase SA. Interaction of carbohydrates with alcohol dehydrogenase: Effect on enzyme activity. J Biosci Bioeng 2015; 120:252-6. [DOI: 10.1016/j.jbiosc.2015.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 09/09/2014] [Accepted: 01/07/2015] [Indexed: 10/24/2022]
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10
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Yahashiri A, Rubach JK, Plapp BV. Effects of cavities at the nicotinamide binding site of liver alcohol dehydrogenase on structure, dynamics and catalysis. Biochemistry 2014; 53:881-94. [PMID: 24437493 PMCID: PMC3969020 DOI: 10.1021/bi401583f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
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A role
for protein dynamics in enzymatic catalysis of hydrogen
transfer has received substantial scientific support, but the connections
between protein structure and catalysis remain to be established.
Valine residues 203 and 207 are at the binding site for the nicotinamide
ring of the coenzyme in liver alcohol dehydrogenase and have been
suggested to facilitate catalysis with “protein-promoting vibrations”
(PPV). We find that the V207A substitution has small effects on steady-state
kinetic constants and the rate of hydrogen transfer; the introduced
cavity is empty and is tolerated with minimal effects on structure
(determined at 1.2 Å for the complex with NAD+ and
2,3,4,5,6-pentafluorobenzyl alcohol). Thus, no evidence is found to
support a role for Val-207 in the dynamics of catalysis. The protein
structures and ligand geometries (including donor–acceptor
distances) in the V203A enzyme complexed with NAD+ and
2,3,4,5,6-pentafluorobenzyl alcohol or 2,2,2-trifluoroethanol (determined
at 1.1 Å) are very similar to those for the wild-type enzyme,
except that the introduced cavity accommodates a new water molecule
that contacts the nicotinamide ring. The structures of the V203A enzyme
complexes suggest, in contrast to previous studies, that the diminished
tunneling and decreased rate of hydride transfer (16-fold, relative
to that of the wild-type enzyme) are not due to differences in ground-state
ligand geometries. The V203A substitution may alter the PPV and the
reorganization energy for hydrogen transfer, but the protein scaffold
and equilibrium thermal motions within the Michaelis complex may be
more significant for enzyme catalysis.
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Affiliation(s)
- Atsushi Yahashiri
- Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242-1109, United States
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11
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Affiliation(s)
- Katarzyna Swiderek
- Institute of Applied Radiation Chemistry, Faculty of Chemistry, Lodz University of Technology , Zeromskiego 116, 90-924 Lodz, Poland
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12
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Kalliokoski T, Olsson TSG, Vulpetti A. Subpocket analysis method for fragment-based drug discovery. J Chem Inf Model 2013; 53:131-41. [PMID: 23327721 DOI: 10.1021/ci300523r] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Although two binding sites might be dissimilar overall, they might still bind the same fragments if they share suitable subpockets. Information about shared subpockets can be therefore used in fragment-based drug design to suggest new fragments or to replace existing fragments within an already known compound. A novel computational method called SubCav is described which allows the similarity searching and alignment of subpockets from a PDB-wide database against a user-defined query. The method is based on pharmacophoric fingerprints combined with a subpocket alignment algorithm. SubCav was shown to be effective in producing reasonable alignments for subpockets with low sequence similarity and be able to retrieve relevant subpockets from a large database of structures including those with different folds. It can also be used to analyze subpockets inside a protein family to facilitate drug design and to rationalize compound selectivity.
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Affiliation(s)
- Tuomo Kalliokoski
- Novartis Institutes for Biomedical Research, Postfach, CH-4002 Basel, Switzerland
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13
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Lai CL, Li YP, Liu CM, Hsieh HS, Yin SJ. Inhibition of human alcohol and aldehyde dehydrogenases by cimetidine and assessment of its effects on ethanol metabolism. Chem Biol Interact 2012; 202:275-82. [PMID: 23220590 DOI: 10.1016/j.cbi.2012.11.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 11/15/2012] [Accepted: 11/19/2012] [Indexed: 12/19/2022]
Abstract
Previous studies have reported that cimetidine, an H2-receptor antagonist used to treat gastric and duodenal ulcers, can inhibit alcohol dehydrogenases (ADHs) and ethanol metabolism. Human alcohol dehydrogenases and aldehyde dehydrogenases (ALDHs), the principal enzymes responsible for metabolism of ethanol, are complex enzyme families that exhibit functional polymorphisms among ethnic groups and distinct tissue distributions. We investigated the inhibition by cimetidine of alcohol oxidation by recombinant human ADH1A, ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2, ADH2, and ADH4, and aldehyde oxidation by ALDH1A1 and ALDH2 at pH 7.5 and a cytosolic NAD(+) concentration. Cimetidine acted as competitive or noncompetitive inhibitors for the ADH and ALDH isozymes/allozymes with near mM inhibition constants. The metabolic interactions between cimetidine and ethanol/acetaldehyde were assessed by computer simulation using the inhibition equations and the determined kinetic constants. At therapeutic drug levels (0.015 mM) and physiologically relevant concentrations of ethanol (10 mM) and acetaldehyde (10 μM) in target tissues, cimetidine could weakly inhibit (<5%) the activities of ADH1B2 and ADH1B3 in liver, ADH2 in liver and small intestine, ADH4 in stomach, and ALDH1A1 in the three tissues, but not significantly affect ADH1A, ADH1B1, ADH1C1/2, or ALDH2. At higher drug levels, which may accumulate in cells (0.2 mM), the activities of the weakly-inhibited enzymes may be decreased more significantly. The quantitative effects of cimetidine on metabolism of ethanol and other physiological substrates of ADHs need further investigation.
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Affiliation(s)
- Ching-Long Lai
- Department of Nursing, Chang Gung University of Science and Technology, Kweishan Township, Taoyuan 33303, Taiwan.
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14
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Plapp BV, Ramaswamy S. Atomic-resolution structures of horse liver alcohol dehydrogenase with NAD(+) and fluoroalcohols define strained Michaelis complexes. Biochemistry 2012; 51:4035-48. [PMID: 22531044 DOI: 10.1021/bi300378n] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Structures of horse liver alcohol dehydrogenase complexed with NAD(+) and unreactive substrate analogues, 2,2,2-trifluoroethanol or 2,3,4,5,6-pentafluorobenzyl alcohol, were determined at 100 K at 1.12 or 1.14 Å resolution, providing estimates of atomic positions with overall errors of ~0.02 Å, the geometry of ligand binding, descriptions of alternative conformations of amino acid residues and waters, and evidence of a strained nicotinamide ring. The four independent subunits from the two homodimeric structures differ only slightly in the peptide backbone conformation. Alternative conformations for amino acid side chains were identified for 50 of the 748 residues in each complex, and Leu-57 and Leu-116 adopt different conformations to accommodate the different alcohols at the active site. Each fluoroalcohol occupies one position, and the fluorines of the alcohols are well-resolved. These structures closely resemble the expected Michaelis complexes with the pro-R hydrogens of the methylene carbons of the alcohols directed toward the re face of C4N of the nicotinamide rings with a C-C distance of 3.40 Å. The oxygens of the alcohols are ligated to the catalytic zinc at a distance expected for a zinc alkoxide (1.96 Å) and participate in a low-barrier hydrogen bond (2.52 Å) with the hydroxyl group of Ser-48 in a proton relay system. As determined by X-ray refinement with no restraints on bond distances and planarity, the nicotinamide rings in the two complexes are slightly puckered (quasi-boat conformation, with torsion angles of 5.9° for C4N and 4.8° for N1N relative to the plane of the other atoms) and have bond distances that are somewhat different compared to those found for NAD(P)(+). It appears that the nicotinamide ring is strained toward the transition state on the path to alcohol oxidation.
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Affiliation(s)
- Bryce V Plapp
- Department of Biochemistry, The University of Iowa, Iowa City, IA 52242, USA.
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15
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Oxidation of methanol, ethylene glycol, and isopropanol with human alcohol dehydrogenases and the inhibition by ethanol and 4-methylpyrazole. Chem Biol Interact 2011; 191:26-31. [DOI: 10.1016/j.cbi.2010.12.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2010] [Revised: 12/04/2010] [Accepted: 12/09/2010] [Indexed: 11/23/2022]
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16
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17
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Dołęga A, Baranowska K, Gudat D, Herman A, Stangret J, Konitz A, Śmiechowski M, Godlewska S. Modeling of the Alcohol Dehydrogenase Active Site: Two Different Modes of Alcohol Binding in Crystals of Zinc and Cadmium Tri-tert-butoxysilanethiolates Evidenced by X-ray Diffraction and Solid-State Vibrational Spectroscopy. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900106] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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Plapp BV. Conformational changes and catalysis by alcohol dehydrogenase. Arch Biochem Biophys 2009; 493:3-12. [PMID: 19583966 DOI: 10.1016/j.abb.2009.07.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 07/01/2009] [Accepted: 07/02/2009] [Indexed: 10/20/2022]
Abstract
As shown by X-ray crystallography, horse liver alcohol dehydrogenase undergoes a global conformational change upon binding of NAD(+) or NADH, involving a rotation of the catalytic domain relative to the coenzyme binding domain and the closing up of the active site to produce a catalytically efficient enzyme. The conformational change requires a complete coenzyme and is affected by various chemical or mutational substitutions that can increase the catalytic turnover by altering the kinetics of the isomerization and rate of dissociation of coenzymes. The binding of NAD(+) is kinetically limited by a unimolecular isomerization (corresponding to the conformational change) that is controlled by deprotonation of the catalytic zinc-water to produce a negatively-charged zinc-hydroxide, which can attract the positively-charged nicotinamide ring. The deprotonation is facilitated by His-51 acting through a hydrogen-bonded network to relay the proton to solvent. Binding of NADH also involves a conformational change, but the rate is very fast. After the enzyme binds NAD(+) and closes up, the substrate displaces the hydroxide bound to the catalytic zinc; this exchange may involve a double displacement reaction where the carboxylate group of a glutamate residue first displaces the hydroxide (inverting the tetrahedral coordination of the zinc), and then the exogenous ligand displaces the glutamate. The resulting enzyme-NAD(+)-alcoholate complex is poised for hydrogen transfer, and small conformational fluctuations may bring the reactants together so that the hydride ion is transferred by quantum mechanical tunneling. In the process, the nicotinamide ring may become puckered, as seen in structures of complexes of the enzyme with NADH. The conformational changes of alcohol dehydrogenase demonstrate the importance of protein dynamics in catalysis.
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Affiliation(s)
- Bryce V Plapp
- Department of Biochemistry, The University of Iowa, Iowa City, IA 52242-1109, USA.
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Meijers R, Cedergren-Zeppezauer E. A variety of electrostatic interactions and adducts can activate NAD(P) cofactors for hydride transfer. Chem Biol Interact 2008; 178:24-8. [PMID: 19028476 DOI: 10.1016/j.cbi.2008.10.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 10/14/2008] [Accepted: 10/15/2008] [Indexed: 11/17/2022]
Abstract
In NAD(P)-dependent enzymes the coenzyme gives or takes a hydride ion, but how the nicotinamide ring is activated to form the transition state for hydride transfer is not clear. On the basis of ultra-high resolution X-ray crystal structures of liver alcohol dehydrogenase (LADH) in complex with NADH and a number of substrate analogues we proposed that the activation of NADH is an integral part of the enzyme mechanism of aldehyde reduction [R. Meijers, R.J. Morris, H.W. Adolph, A. Merli, V.S. Lamzin, E.S. Cedergren-Zeppezauer, On the enzymatic activation of NADH, The Journal of Biological Chemistry 276(12) (2001) 9316-9321, %U http://www.ncbi.nlm.nih.gov/pubmed/11134046; R. Meijers, H.-W. Adolph, Z. Dauter, K.S. Wilson, V.S. Lamzin, E.S. Cedergren-Zeppezauer, Structural evidence for a ligand coordination switch in liver alcohol dehydrogenase, Biochemistry 46(18) (2007) 5446-5454, %U http://www.ncbi.nlm.nih.gov/pubmed/17429946]. We observed a nicotinamide with a severely distorted pyridine ring and a water molecule in close proximity to the ring. Quantum chemical calculations indicated that (de)protonation of the water molecule can be directly coupled to activation of NADH for hydride transfer. A systematic search of the Protein Data Bank (PDB) for atoms that come within van der Waals distance of the pyridine ring of the nicotinamide reveals that a large number of NAD(P)-containing protein complexes are involved in electrostatic interactions with the enzymatic environment. Using the deposited diffraction data to analyze the cofactor and its surroundings, we observe several adducts between protein atoms and the pyridine ring that were not previously reported. This further indicates that the enzymatic activation of NAD(P) induced by electrostatic interactions is an essential part of the hydride transfer mechanism.
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Affiliation(s)
- Rob Meijers
- Synchrotron Soleil, L'Orme des Merisiers, Saint Aubin, France.
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Yang J, Dong XC, Leng Y. Application of FTTP to alpha-helix or beta-strand motifs. J Theor Biol 2006; 242:199-219. [PMID: 16616204 DOI: 10.1016/j.jtbi.2006.02.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2005] [Revised: 02/17/2006] [Accepted: 02/21/2006] [Indexed: 11/28/2022]
Abstract
Information concerning protein structure is widely dispersed and cannot easily and rapidly be processed by the biological community. We present a database of tendentious factors of three states of tripeptide units from PDB database, called a bank of tendentious factors of three states of three-peptide units (FTTP). The FTTP database was constructed based on conformational dihedral angle (varphi,psi) library of 20(3) peptide triplets by exhaustively searching through PDB databases. We introduce the FTTP database for the analysis of characteristics common to relative conformational biases of all peptide triplets, especially finding some motifs apt to alpha-helix and beta-strand. Our results show that this will provide a platform for studies of short peptide motifs, folding codons, secondary structure and three-dimensional (3D) structure of proteins. Moreover, FTTP is a unique resource that will allow a comprehensive characterization of peptide triplets and thus improve our understanding of sequence-structure relationship, refined domains, 3D structures, and their associated function. We believe the FTTP database will help biologists in increasing the efficiency of finding useful and relevant information regarding structure-function relationship of proteins. Therefore, this approach will play an important role in protein folding, protein engineering, molecular design, and proteomics.
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Affiliation(s)
- Jie Yang
- State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing 210093, PR China.
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Collins XH, Harmon SD, Kaduce TL, Berst KB, Fang X, Moore SA, Raju TV, Falck JR, Weintraub NL, Duester G, Plapp BV, Spector AA. ω-Oxidation of 20-Hydroxyeicosatetraenoic Acid (20-HETE) in Cerebral Microvascular Smooth Muscle and Endothelium by Alcohol Dehydrogenase 4. J Biol Chem 2005; 280:33157-64. [PMID: 16081420 DOI: 10.1074/jbc.m504055200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
20-Carboxyeicosatetraenoic acid (20-COOH-AA) is a bioactive metabolite of 20-hydroxyeicosatetraenoic acid (20-HETE), an eicosanoid that produces vasoconstriction in the cerebral circulation. We found that smooth muscle (MSMC) and endothelial (MEC) cultures obtained from mouse brain microvessels convert [3H]20-HETE to 20-COOH-AA, indicating that the cerebral vasculature can produce this metabolite. The [3H]20-COOH-AA accumulated primarily in the culture medium, together with additional radiolabeled metabolites identified as the chain-shortened dicarboxylic acids 18-COOH-18:4, 18-COOH-18:3, and 16-COOH-16:3. N-Heptylformamide, a potent inhibitor of alcohol dehydrogenase (ADH), decreased the conversion of [3H]20-HETE to 20-COOH-AA by the MSMC and MEC and also by isolated mouse brain microvessels. Purified mouse and human ADH4, human ADH3, and horse liver ADH1 efficiently oxidized 20-HETE, and ADH4 and ADH3 were detected in MSMC and MEC by Western blotting. N-Heptylformamide inhibited the oxidation of 20-HETE by mouse and human ADH4 but not by ADH3. These results demonstrated that cerebral microvessels convert 20-HETE to 20-COOH-AA and that ADH catalyzes the reaction. Although ADH4 and ADH3 are expressed in MSMC and MEC, the inhibition produced by N-heptylformamide suggests that ADH4 is primarily responsible for 20-COOH-AA formation in the cerebral microvasculature.
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Affiliation(s)
- Xixuan H Collins
- Department of Biochemistry, Carver College of Medicine, The University of Iowa, Iowa City, Iowa 52242, USA
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Gibbons BJ, Hurley TD. Structure of Three Class I Human Alcohol Dehydrogenases Complexed with Isoenzyme Specific Formamide Inhibitors,. Biochemistry 2004; 43:12555-62. [PMID: 15449945 DOI: 10.1021/bi0489107] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Formamides are aldehyde analogues that have demonstrated potent and selective inhibition of human alcohol dehydrogenase isoenzymes. The alphaalpha, beta(1)beta(1), gamma(2)gamma(2), and sigmasigma isoforms have all been found to be strongly inhibited by substituted formamides. In this paper, the structure of the alphaalpha isoform of human alcohol dehydrogenase complexed with N-cyclopentyl-N-cyclobutylformamide was determined by X-ray crystallography to 2.5 A resolution, the beta(1)beta(1) isoform of human alcohol dehydrogenase complexed with N-benzylformamide and with N-heptylformamide was determined to 1.6 and 1.65 A resolution, respectively, and the structure of the gamma(2)gamma(2) isoform complexed with N-1-methylheptylformamide was determined to 1.45 A resolution. These structures provide the first substrate-level view of the local structural differences that give rise to the individual substrate preferences shown by these highly related isoenzymes. Consistent with previous work, the carbonyl oxygen of the inhibitors interacts directly with the catalytic zinc and the hydroxyl group of Thr48 (Ser48 for gamma(2)gamma(2)) of the enzyme. The benzene ring of N-benzylformamide and the carbon chains of N-heptylformamide and N-1-methylheptylformamide interact with the sides of the hydrophobic substrate pocket whose size and shape is dictated by residue exchanges between the beta(1)beta(1) and gamma(2)gamma(2) isoenzymes. In particular, the exchange of Ser for Thr at position 48 and the exchange of Val for Leu at position 141 in the gamma(2)gamma(2) isoenzyme create an environment with stereoselectivity for the R-enantiomer of the branched N-1-methylheptylformamide inhibitor in this isoenzyme. The primary feature of the alphaalpha isoform is the Ala for Phe93 exchange that enlarges the active site near the catalytic zinc and creates the specificity for the branched N-cyclopentyl-N-cyclobutylformamide inhibitor, which shows the greatest selectivity for this unique isoenzyme of any of the formamide inhibitors.
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Affiliation(s)
- Brian J Gibbons
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, Room MS 4017, Indianapolis, Indiana 46202-5122, USA
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