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Zhang X, Xin J, Wang Z, Wu W, Liu Y, Min Z, Xin Y, Liu B, He J, Zhang X, Xu X. Structural basis of a bi-functional malonyl-CoA reductase (MCR) from the photosynthetic green non-sulfur bacterium Roseiflexus castenholzii. mBio 2023; 14:e0323322. [PMID: 37278533 PMCID: PMC10470521 DOI: 10.1128/mbio.03233-22] [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: 11/23/2022] [Accepted: 04/10/2023] [Indexed: 06/07/2023] Open
Abstract
Malonyl-CoA reductase (MCR) is a NADPH-dependent bi-functional enzyme that performs alcohol dehydrogenase and aldehyde dehydrogenase (CoA-acylating) activities in the N- and C-terminal fragments, respectively. It catalyzes the two-step reduction of malonyl-CoA to 3-hydroxypropionate (3-HP), a key reaction in the autotrophic CO2 fixation cycles of Chloroflexaceae green non-sulfur bacteria and the archaea Crenarchaeota. However, the structural basis underlying substrate selection, coordination, and the subsequent catalytic reactions of full-length MCR is largely unknown. For the first time, we here determined the structure of full-length MCR from the photosynthetic green non-sulfur bacterium Roseiflexus castenholzii (RfxMCR) at 3.35 Å resolution. Furthermore, we determined the crystal structures of the N- and C-terminal fragments bound with reaction intermediates NADP+ and malonate semialdehyde (MSA) at 2.0 Å and 2.3 Å, respectively, and elucidated the catalytic mechanisms using a combination of molecular dynamics simulations and enzymatic analyses. Full-length RfxMCR was a homodimer of two cross-interlocked subunits, each containing four tandemly arranged short-chain dehydrogenase/reductase (SDR) domains. Only the catalytic domains SDR1 and SDR3 incorporated additional secondary structures that changed with NADP+-MSA binding. The substrate, malonyl-CoA, was immobilized in the substrate-binding pocket of SDR3 through coordination with Arg1164 and Arg799 of SDR4 and the extra domain, respectively. Malonyl-CoA was successively reduced through protonation by the Tyr743-Arg746 pair in SDR3 and the catalytic triad (Thr165-Tyr178-Lys182) in SDR1 after nucleophilic attack from NADPH hydrides. IMPORTANCE The bi-functional MCR catalyzes NADPH-dependent reduction of malonyl-CoA to 3-HP, an important metabolic intermediate and platform chemical, from biomass. The individual MCR-N and MCR-C fragments, which contain the alcohol dehydrogenase and aldehyde dehydrogenase (CoA-acylating) activities, respectively, have previously been structurally investigated and reconstructed into a malonyl-CoA pathway for the biosynthetic production of 3-HP. However, no structural information for full-length MCR has been available to illustrate the catalytic mechanism of this enzyme, which greatly limits our capacity to increase the 3-HP yield of recombinant strains. Here, we report the cryo-electron microscopy structure of full-length MCR for the first time and elucidate the mechanisms underlying substrate selection, coordination, and catalysis in the bi-functional MCR. These findings provide a structural and mechanistic basis for enzyme engineering and biosynthetic applications of the 3-HP carbon fixation pathways.
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Affiliation(s)
- Xin Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
- Photosynthesis Research Center, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Jiyu Xin
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Zhiguo Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Wenping Wu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Yutong Liu
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Zhenzhen Min
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Yueyong Xin
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Bing Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Jun He
- CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xingwei Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
| | - Xiaoling Xu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences and the Affiliated Hospital, Key Laboratory of Aging and Cancer Biology of Zhejiang Province, Hangzhou Normal University, Hangzhou, China
- Photosynthesis Research Center, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
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Zheng C, Wang Z, Wang Q, Wang S, Lao S, He J, Chen Z. Efficient preparation of the chiral intermediate of luliconazole with Lactobacillus kefir alcohol dehydrogenase through rational rearrangement of the substrate binding pocket. MOLECULAR CATALYSIS 2021. [DOI: 10.1016/j.mcat.2021.111639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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Verma R, Ellis JM, Mitchell-Koch KR. Dynamic Preference for NADP/H Cofactor Binding/Release in E. coli YqhD Oxidoreductase. Molecules 2021; 26:E270. [PMID: 33430436 PMCID: PMC7826944 DOI: 10.3390/molecules26020270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/24/2020] [Accepted: 01/04/2021] [Indexed: 11/16/2022] Open
Abstract
YqhD, an E. coli alcohol/aldehyde oxidoreductase, is an enzyme able to produce valuable bio-renewable fuels and fine chemicals from a broad range of starting materials. Herein, we report the first computational solution-phase structure-dynamics analysis of YqhD, shedding light on the effect of oxidized and reduced NADP/H cofactor binding on the conformational dynamics of the biocatalyst using molecular dynamics (MD) simulations. The cofactor oxidation states mainly influence the interdomain cleft region conformations of the YqhD monomers, involved in intricate cofactor binding and release. The ensemble of NADPH-bound monomers has a narrower average interdomain space resulting in more hydrogen bonds and rigid cofactor binding. NADP-bound YqhD fluctuates between open and closed conformations, while it was observed that NADPH-bound YqhD had slower opening/closing dynamics of the cofactor-binding cleft. In the light of enzyme kinetics and structural data, simulation findings have led us to postulate that the frequently sampled open conformation of the cofactor binding cleft with NADP leads to the more facile release of NADP while increased closed conformation sampling during NADPH binding enhances cofactor binding affinity and the aldehyde reductase activity of the enzyme.
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Affiliation(s)
- Rajni Verma
- Department of Chemistry, McKinley Hall, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA
| | - Jonathan M. Ellis
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA;
| | - Katie R. Mitchell-Koch
- Department of Chemistry, McKinley Hall, Wichita State University, 1845 Fairmount, Wichita, KS 67260, USA
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4
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Croitoru A, Babin M, Myllykallio H, Gondry M, Aleksandrov A. Cyclodipeptide Synthases of the NYH Subfamily Recognize tRNA Using an α-Helix Enriched with Positive Residues. Biochemistry 2020; 60:64-76. [PMID: 33331769 DOI: 10.1021/acs.biochem.0c00761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cyclodipeptide synthases (CDPSs) perform nonribosomal protein synthesis using two aminoacyl-tRNA substrates to produce cyclodipeptides. At present, there are no structural details of the CDPS:tRNA interaction available. Using AlbC, a CDPS that produces cyclo(l-Phe-l-Phe), the interaction between AlbC and its Phe-tRNA substrate was investigated. Simulations of models of the AlbC:tRNA complex, proposed by rigid-body docking or homology modeling, demonstrated that interactions with residues of an AlbC α-helix, α4, significantly contribute to the free energy of binding of AlbC to tRNA. Individual residue contributions to the tRNA binding free energy of the discovered binding mode explain well the available biochemical data, and the results of in vivo assay experiments performed in this work and guided by simulations. In molecular dynamics simulations, the phenylalanyl group predominantly occupied the two positions observed in the experimental structure of AlbC in the dipeptide intermediate state, suggesting that tRNAs of the first and second substrates interact with AlbC in a similar manner. Overall, given the high degree of sequence and structural similarity among the members of the CDPS NYH protein subfamily, the mechanism of the protein:tRNA interaction is expected to be pertinent to a wide range of proteins interacting with tRNA.
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Affiliation(s)
- Anastasia Croitoru
- Laboratoire d'Optique et Biosciences (CNRS UMR7645, INSERM U1182), Ecole Polytechnique, Institut polytechnique de Paris, F-91128 Palaiseau, France
| | - Morgan Babin
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Hannu Myllykallio
- Laboratoire d'Optique et Biosciences (CNRS UMR7645, INSERM U1182), Ecole Polytechnique, Institut polytechnique de Paris, F-91128 Palaiseau, France
| | - Muriel Gondry
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Alexey Aleksandrov
- Laboratoire d'Optique et Biosciences (CNRS UMR7645, INSERM U1182), Ecole Polytechnique, Institut polytechnique de Paris, F-91128 Palaiseau, France
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Adesina AS, Świderek K, Luk LYP, Moliner V, Allemann RK. Electric Field Measurements Reveal the Pivotal Role of Cofactor-Substrate Interaction in Dihydrofolate Reductase Catalysis. ACS Catal 2020; 10:7907-7914. [PMID: 32905264 PMCID: PMC7467645 DOI: 10.1021/acscatal.0c01856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 06/18/2020] [Indexed: 12/31/2022]
Abstract
![]()
The
contribution of ligand–ligand electrostatic interaction
to transition state formation during enzyme catalysis has remained
unexplored, even though electrostatic forces are known to play a major
role in protein functions and have been investigated by the vibrational
Stark effect (VSE). To monitor electrostatic changes along important
steps during catalysis, we used a nitrile probe (T46C-CN) inserted
proximal to the reaction center of three dihydrofolate reductases
(DHFRs) with different biophysical properties, Escherichia
coli DHFR (EcDHFR), its conformationally impaired variant
(EcDHFR-S148P), and Geobacillus stearothermophilus DHFR (BsDHFR). Our combined experimental and computational approach
revealed that the electric field projected by the substrate toward
the probe negates those exerted by the cofactor when both are bound
within the enzymes. This indicates that compared to previous models
that focus exclusively on subdomain reorganization and protein–ligand
contacts, ligand–ligand interactions are the key driving force
to generate electrostatic environments conducive for catalysis.
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Affiliation(s)
- Aduragbemi S. Adesina
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Katarzyna Świderek
- Departament de Química Física i Analítica, Universitat Jaume I, 12071 Castellón, Spain
| | - Louis Y. P. Luk
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Vicent Moliner
- Departament de Química Física i Analítica, Universitat Jaume I, 12071 Castellón, Spain
| | - Rudolf K. Allemann
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, United Kingdom
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Zhang C, Min Z, Liu X, Wang C, Wang Z, Shen J, Tang W, Zhang X, Liu D, Xu X. Tolrestat acts atypically as a competitive inhibitor of the thermostable aldo-keto reductase Tm1743 from Thermotoga maritima. FEBS Lett 2019; 594:564-580. [PMID: 31573681 DOI: 10.1002/1873-3468.13630] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/17/2019] [Accepted: 09/29/2019] [Indexed: 12/28/2022]
Abstract
Tolrestat and epalrestat have been characterized as noncompetitive inhibitors of aldo-ketone reductase 1B1 (AKR1B1), a leading drug target for the treatment of type 2 diabetes complications. However, clinical applications are limited for most AKR1B1 inhibitors due to adverse effects of cross-inhibition with other AKRs. Here, we report an atypical competitive binding and inhibitory effect of tolrestat on the thermostable AKR Tm1743 from Thermotoga maritima. Analysis of the Tm1743 crystal structure in complex with tolrestat alone and epalrestat-NADP+ shows that tolrestat, but not epalrestat, binding triggers dramatic conformational changes in the anionic site and cofactor binding pocket that prevents accommodation of NADP+ . Enzymatic and molecular dynamics simulation analyses further confirm tolrestat as a competitive inhibitor of Tm1743.
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Affiliation(s)
- Chenyun Zhang
- School of Medicine, Hangzhou Normal University, China
| | - Zhenzhen Min
- School of Medicine, Hangzhou Normal University, China
| | - Xuemeng Liu
- School of Medicine, Hangzhou Normal University, China
| | - Chao Wang
- School of Medicine, Hangzhou Normal University, China
| | - Zhiguo Wang
- School of Medicine, Hangzhou Normal University, China
| | - Jiejie Shen
- School of Medicine, Hangzhou Normal University, China
| | - Wanrong Tang
- School of Medicine, Hangzhou Normal University, China
| | - Xin Zhang
- School of Medicine, Hangzhou Normal University, China
| | - Dan Liu
- School of Medicine, Hangzhou Normal University, China
| | - Xiaoling Xu
- School of Medicine, Hangzhou Normal University, China.,Institute of Cardiovascular Disease Research, The Affiliated Hospital of Hangzhou Normal University, China
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7
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Shevkunov SV. Water Vapor Nucleation on a Surface with Nanoscopic Grooves. 2. Features of Thermodynamic Behavior. COLLOID JOURNAL 2019. [DOI: 10.1134/s1061933x19030141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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8
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Qu G, Fu M, Zhao L, Liu B, Liu P, Fan W, Ma JA, Sun Z. Computational Insights into the Catalytic Mechanism of Bacterial Carboxylic Acid Reductase. J Chem Inf Model 2019; 59:832-841. [PMID: 30688451 DOI: 10.1021/acs.jcim.8b00763] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ge Qu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Mingxing Fu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Lili Zhao
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing 211816, China
| | - Beibei Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Pi Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Wenchao Fan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Jun-An Ma
- Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, and Tianjin Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Zhoutong Sun
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
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9
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Verma R, Mitchell-Koch K. In Silico Studies of Small Molecule Interactions with Enzymes Reveal Aspects of Catalytic Function. Catalysts 2017; 7:212. [PMID: 30464857 PMCID: PMC6241538 DOI: 10.3390/catal7070212] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Small molecules, such as solvent, substrate, and cofactor molecules, are key players in enzyme catalysis. Computational methods are powerful tools for exploring the dynamics and thermodynamics of these small molecules as they participate in or contribute to enzymatic processes. In-depth knowledge of how small molecule interactions and dynamics influence protein conformational dynamics and function is critical for progress in the field of enzyme catalysis. Although numerous computational studies have focused on enzyme-substrate complexes to gain insight into catalytic mechanisms, transition states and reaction rates, the dynamics of solvents, substrates, and cofactors are generally less well studied. Also, solvent dynamics within the biomolecular solvation layer play an important part in enzyme catalysis, but a full understanding of its role is hampered by its complexity. Moreover, passive substrate transport has been identified in certain enzymes, and the underlying principles of molecular recognition are an area of active investigation. Enzymes are highly dynamic entities that undergo different conformational changes, which range from side chain rearrangement of a residue to larger-scale conformational dynamics involving domains. These events may happen nearby or far away from the catalytic site, and may occur on different time scales, yet many are related to biological and catalytic function. Computational studies, primarily molecular dynamics (MD) simulations, provide atomistic-level insight and site-specific information on small molecule interactions, and their role in conformational pre-reorganization and dynamics in enzyme catalysis. The review is focused on MD simulation studies of small molecule interactions and dynamics to characterize and comprehend protein dynamics and function in catalyzed reactions. Experimental and theoretical methods available to complement and expand insight from MD simulations are discussed briefly.
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Affiliation(s)
- Rajni Verma
- Department of Chemistry, McKinley Hall, Wichita State University, 1845 Fairmount, Wichita, KS 67260-0051, USA
| | - Katie Mitchell-Koch
- Department of Chemistry, McKinley Hall, Wichita State University, 1845 Fairmount, Wichita, KS 67260-0051, USA
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10
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Insight into the molecular mechanism about lowered dihydrofolate binding affinity to dihydrofolate reductase-like 1 (DHFRL1). J Mol Model 2013; 19:5187-98. [PMID: 24122410 DOI: 10.1007/s00894-013-2018-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 09/15/2013] [Indexed: 10/26/2022]
Abstract
Human dihydrofolate reductase-like 1 (DHFRL1) has been identified as a second human dihydrofolate reductase (DHFR) enzyme. Although DHFRL1 have high sequence homology with human DHFR, dihydrofolate (DHF) exhibits a lowered binding affinity to DHFRL1 and the corresponding molecular mechanism is still unknown. To address this question, we studied the binding of DHF to DHFRL1 and DHFR by using molecular dynamics simulation. Moreover, to investigate the role the 24th residue of DHFR/DHFRL1 plays in DHF binding, R24W DHFRL1 mutant was also studied. The van der Waals interaction are more crucial for the total DHF binding energies, while the difference between the DHF binding energies of human DHFR and DHFRL1 can be attributed to the electrostatic interaction and the polar desolvation free energy.More specifically, lower DHF affinity to DHFRL1 can be mainly attributed to the reduction of net electrostatic interactions of residues Arg32 and Gln35 of DHFRL1 with DHF as being affected by Arg24. The side chain of Arg24 in DHFRL1 can extend deeply into the binding sites of DHF and NADPH, and disturb the DHF binding by steric effect, which rarely happens in human DHFR and R24W DHFRL1 mutant. Additionally, the conformation of loop I in DHFRL1 was also studied in this work. Interestingly, the loop conformation resemble to normal closed state of Escherichia coli DHFR other than the closed state of human DHFR. We hope this work will be useful to understand the general characteristics of DHFRL1.
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11
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Chipot C. Frontiers in free-energy calculations of biological systems. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2013. [DOI: 10.1002/wcms.1157] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Christophe Chipot
- Laboratoire International Associé CNRS-UIUC; Unité mixte de recherche 7565; Université de Lorraine; Cedex France
- Beckman Institute for Advanced Science and Technology; University of Illinois; Urbana-Champaign IL USA
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12
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Sharma S, Bhaumik P, Schmitz W, Venkatesan R, Hiltunen JK, Conzelmann E, Juffer AH, Wierenga RK. The Enolization Chemistry of a Thioester-Dependent Racemase: The 1.4 Å Crystal Structure of a Reaction Intermediate Complex Characterized by Detailed QM/MM Calculations. J Phys Chem B 2012; 116:3619-29. [DOI: 10.1021/jp210185m] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Satyan Sharma
- Biocenter Oulu and Department
of Biochemistry, University of Oulu, P.O.
Box 3000, Oulu, FI-90014, Finland
| | - Prasenjit Bhaumik
- Protein Structure Section, Macromolecular
Crystallography Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
| | - Werner Schmitz
- Theodor-Boveri-Institut für
Biowissenschaften (Biozentrum) der Universität Würzburg, Am Hubland, D-97074 Würzburg,
Germany
| | - Rajaram Venkatesan
- Biocenter Oulu and Department
of Biochemistry, University of Oulu, P.O.
Box 3000, Oulu, FI-90014, Finland
| | - J. Kalervo Hiltunen
- Biocenter Oulu and Department
of Biochemistry, University of Oulu, P.O.
Box 3000, Oulu, FI-90014, Finland
| | - Ernst Conzelmann
- Theodor-Boveri-Institut für
Biowissenschaften (Biozentrum) der Universität Würzburg, Am Hubland, D-97074 Würzburg,
Germany
| | - André H. Juffer
- Biocenter Oulu and Department
of Biochemistry, University of Oulu, P.O.
Box 3000, Oulu, FI-90014, Finland
| | - Rik K. Wierenga
- Biocenter Oulu and Department
of Biochemistry, University of Oulu, P.O.
Box 3000, Oulu, FI-90014, Finland
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13
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Doron D, Major DT, Kohen A, Thiel W, Wu X. Hybrid Quantum and Classical Simulations of the Dihydrofolate Reductase Catalyzed Hydride Transfer Reaction on an Accurate Semi-Empirical Potential Energy Surface. J Chem Theory Comput 2011; 7:3420-37. [PMID: 26598171 DOI: 10.1021/ct2004808] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dihydrofolate reductase (DHFR) catalyzes the reduction of 7,8-dihydrofolate by nicotinamide adenine dinucleotide phosphate hydride (NADPH) to form 5,6,7,8-tetrahydrofolate and oxidized nicotinamide. DHFR is a small, flexible, monomeric protein with no metals or SS bonds and serves as one of the enzymes commonly used to examine basic aspects in enzymology. In the current work, we present extensive benchmark calculations for several model reactions in the gas phase that are relevant to the DHFR catalyzed hydride transfer. To this end, we employ G4MP2 and CBS-QB3 ab initio calculations as well as numerous density functional theory methods. Using these results, we develop two specific reaction parameter (SRP) Hamiltonians based on the semiempirical AM1 method. The first generation SRP Hamiltonian does not account for dispersion, while the second generation SRP accounts for dispersion implicitly via the AM1 core-repulsion functions. These SRP semiempirical Hamiltonians are subsequently used in hybrid quantum mechanics/molecular mechanics simulations of the DHFR catalyzed reaction. Finally, kinetic isotope effects are computed using a mass-perturbation-based path-integral approach.
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Affiliation(s)
- Dvir Doron
- Department of Chemistry, The Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University , Ramat-Gan 52900, Israel
| | - Dan Thomas Major
- Department of Chemistry, The Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University , Ramat-Gan 52900, Israel
| | - Amnon Kohen
- Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States
| | - Walter Thiel
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Xin Wu
- Max-Planck-Institut für Kohlenforschung , Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
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Maitarad P, Kamchonwongpaisan S, Vanichtanankul J, Vilaivan T, Yuthavong Y, Hannongbua S. Interactions between cycloguanil derivatives and wild type and resistance-associated mutant Plasmodium falciparum dihydrofolate reductases. J Comput Aided Mol Des 2009; 23:241-52. [PMID: 19156529 DOI: 10.1007/s10822-008-9254-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Accepted: 11/20/2008] [Indexed: 11/29/2022]
Abstract
Comparative molecular field analysis (CoMFA) and quantum chemical calculations were performed on cycloguanil (Cyc) derivatives of the wild type and the quadruple mutant (Asn51Ile, Cys59Arg, Ser108Asn, Ile164Leu) of Plasmodium falciparum dihydrofolate reductase (PfDHFR). The represented CoMFA models of wild type (r(2) = 0.727 and r(2) = 0.985) and mutant type (r(2) = 0.786 and r(2) = 0.979) can describe the differences of the Cyc structural requirements for the two types of PfDHFR enzymes and can be useful to guide the design of new inhibitors. Moreover, the obtained particular interaction energies between the Cyc and the surrounding residues in the binding pocket indicated that Asn108 of mutant enzyme was the cause of Cyc resistance by producing steric clash with p-Cl of Cyc. Consequently, comparing the energy contributions with the potent flexible WR99210 inhibitor, it was found that the key mutant residue, Asn108, demonstrates attractive interaction with this inhibitor and some residues, Leu46, Ile112, Pro113, Phe116, and Leu119, seem to perform as second binding site with WR99210. Therefore, quantum chemical calculations can be useful for investigating residue interactions to clarify the cause of drug resistance.
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Affiliation(s)
- Phornphimon Maitarad
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
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15
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Free Energy Calculations: Use and Limitations in Predicting Ligand Binding Affinities. REVIEWS IN COMPUTATIONAL CHEMISTRY 2007. [DOI: 10.1002/9780470125939.ch4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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16
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17
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Cummins PL, Gready JE. The Influence of Starting Coordinates in Free Energy Simulations of Ligand Binding to Dihydrofolate Reductase. MOLECULAR SIMULATION 2006. [DOI: 10.1080/08927029508024052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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18
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Hayward S, Kitao A. Molecular dynamics simulations of NAD+-induced domain closure in horse liver alcohol dehydrogenase. Biophys J 2006; 91:1823-31. [PMID: 16714351 PMCID: PMC1544320 DOI: 10.1529/biophysj.106.085910] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Horse liver alcohol dehydrogenase is a homodimer, the protomer having a coenzyme-binding domain and a catalytic domain. Using all available x-ray structures and 50 ns of molecular dynamics simulations, we investigated the mechanism of NAD+-induced domain closure. When the well-known loop at the domain interface was modeled to its conformation in the closed structure, the NAD+-induced domain closure from the open structure could be simulated with remarkable accuracy. Native interactions in the closed structure between Arg369, Arg47, His51, Ala317, Phe319, and NAD+ were seen to form at different stages during domain closure. Removal of the Arg369 side-chain charge resulted in the loss of the tendency to close, verifying that specific interactions do help drive the domains closed. Further simulations and a careful analysis of x-ray structures suggest that the loop prevents domain closure in the absence of NAD+, and a cooperative mechanism operates between the subunits for domain closure. This cooperative mechanism explains the role of the loop as a block to closure because in the absence of NAD+ it would prevent the occurrence of an unliganded closed subunit when the other subunit closes on NAD+. Simulations that started with one subunit open and one closed supported this.
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Affiliation(s)
- Steven Hayward
- School of Computing Sciences and School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom.
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19
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Ferrer S, Silla E, Tuñón I, Martí S, Moliner V. Catalytic Mechanism of Dihydrofolate Reductase Enzyme. A Combined Quantum-Mechanical/Molecular-Mechanical Characterization of the N5 Protonation Step. J Phys Chem B 2003. [DOI: 10.1021/jp0354898] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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Castillo R, Andrés J, Moliner V. Catalytic Mechanism of Dihydrofolate Reductase Enzyme. A Combined Quantum-Mechanical/Molecular-Mechanical Characterization of Transition State Structure for the Hydride Transfer Step. J Am Chem Soc 1999. [DOI: 10.1021/ja9843019] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- R. Castillo
- Contribution from the Departament de Ciències Experimentals, Universitat Jaume I, Castelló, Spain
| | - J. Andrés
- Contribution from the Departament de Ciències Experimentals, Universitat Jaume I, Castelló, Spain
| | - V. Moliner
- Contribution from the Departament de Ciències Experimentals, Universitat Jaume I, Castelló, Spain
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21
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Archontis G, Simonson T, Moras D, Karplus M. Specific amino acid recognition by aspartyl-tRNA synthetase studied by free energy simulations. J Mol Biol 1998; 275:823-46. [PMID: 9480772 DOI: 10.1006/jmbi.1997.1470] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Specific amino acid binding by aminoacyl-tRNA synthetases is necessary for correct translation of the genetic code. To obtain insight into the origin of the specificity, the binding to aspartyl-tRNA synthetase (AspRS) of the negatively charged substrate aspartic acid and the neutral analogue asparagine are compared by use of molecular dynamics and free energy simulations. Simulations of the Asn-AspRS complex show that although Asn cannot bind in the same position as Asp, several possible positions exist 1.5 to 2 A away from the Asp site. The binding free energy of Asn in three of these positions was compared to that of Asp through alchemical free energy simulations, in which Asp is gradually mutated ito Asn in the complex with the enzyme. To correctly account for the electrostatic interactions in the system (including bulk solvent), a recently developed hybrid approach was used, in which the region of the mutation site is treated microscopically, whereas distant protein and solvent are treated by continuum electrostatics. Seven free energy simulations were performed in the protein and two in solution. The various Asn positions and orientations sampled at the Asn endpoints of the protein simulations yielded very similar free energy differences. The calculated Asp-->Asn free energy change is 79.8(+/-1.5) kcal/mol in solution and 95.1(+/-2.8) kcal/mol in the complex with the protein. Thus, the substrate Asp is predicted to bind much more strongly than Asn, with a binding free energy difference of 15.3 kcal/mol. This implies that erroneous binding of Asn by AspRS is highly improbable, and cannot account for any errors in the translation of the genetic code. Almost all of the protein contributions to the Asp versus Asn binding free energy difference arise from an arginine and a lysine residue that hydrogen bond to the substrate carboxylate group and an Asp and a Glu that hydrogen bond to these; all four amino acid residues are completely conserved in AspRSs. The protein effectively "solvates" the Asp side-chain more strongly than water does. The simulations are analyzed to determine the interactions that Asn is able to make in the binding pocket, and which sequence differences between AspRS and the highly homologous AsnRS are important for modifying the amino acid specificity. A double or triple mutation of AspRS that could make it specific for Asn is proposed, and supported by preliminary simulations of a mutant complex.
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Affiliation(s)
- G Archontis
- Laboratoire de Chimie Biophysique, Institut Le Bel, Université Louis Pasteur, 4 rue Blaise Pascal, Strasbourg, 67000, France
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22
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Transition structures for hydride transfer reactions in vacuo and their role in enzyme catalysis. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0166-1280(96)04670-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Andrés J, Moliner V, Safont VS, Domingo LR, Picher MT. On Transition Structures for Hydride Transfer Step in Enzyme Catalysis. A Comparative Study on Models of Glutathione Reductase Derived from Semiempirical, HF, and DFT Methods. J Org Chem 1996; 61:7777-7783. [PMID: 11667733 DOI: 10.1021/jo960803y] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
As a model of the chemical reactions that take place in the active site of gluthatione reductase, the nature of the molecular mechanism for the hydride transfer step has been characterized by means of accurate quantum chemical characterizations of transition structures. The calculations have been carried out with analytical gradients at AM1 and PM3 semiempirical procedures, ab initio at HF level with 3-21G, 4-31G, 6-31G, and 6-31G basis sets and BP86 and BLYP as density functional methods. The results of this study suggest that the endo relative orientation on the substrate imposed by the active site is optimal in polarizing the C4-Ht bond and situating the system in the neighborhood of the quadratic region of the transition structure associated to the hydride transfer step on potential energy surface. The endo arrangement of the transition structure results in optimal frontier HOMO orbital interaction between NADH and FAD partners. The geometries of the transition structures and the corresponding transition vectors, that contain the fundamental information relating reactive fluctuation patterns, are model independent and weakly dependent on the level of theory used to determine them. A comparison between simple and complex molecular models shows that there is a minimal set of coordinates describing the essentials of hydride transfer step. The analysis of transition vector components suggests that the primary and secondary kinetic isotope effects can be strongly coupled, and this prompted the calculation of deuterium and tritium primary, secondary, and primary and secondary kinetic isotope effects. The results obtained agree well with experimental data and demonstrate this coupling.
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Affiliation(s)
- Juan Andrés
- Departament de Ciències Experimentals, Universitat Jaume I, Box 224, 12080 Castelló, Spain, and Departament de Química Orgànica, Universitat de València, Dr. Moliner 50, 46100 Burjassot, València, Spain
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24
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A molecular dynamics study of the inhibition of chicken dihydrofolate reductase by a phenyl triazine. J Comput Chem 1995. [DOI: 10.1002/jcc.540161107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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25
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Peräkylä M, Pakkanen TA. Model assembly study of the ligand binding by p-hydroxybenzoate hydroxylase: correlation between the calculated binding energies and the experimental dissociation constants. Proteins 1995; 21:22-9. [PMID: 7716166 DOI: 10.1002/prot.340210104] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The energies of binding of seven ligands by p-hydroxybenzoate hydroxylase (PHBH) were calculated theoretically. Direct enzyme-ligand interaction energies were calculated using the ab initio quantum mechanical model assembly of the active site at the 3-21G level. Solvation energies of the ligands needed in the evaluation of the binding energies were calculated with the semiempirical AM1-SM2 method and the long-range electrostatic interaction energies between the ligands and the protein matrix classically using the static charge distributions of the ligands and the protein. Energies for proton-transfer between the ligands' OH or SH substituent at position 4 and the active-site tyrosine within the ab initio model assemblies were calculated and compared to the corresponding pKas in aqueous solution. Excluding 3,4-dihydroxybenzoate, the natural product of PHBH, a linear relationship between the calculated binding energies and the experimental binding free energies was found with a correlation coefficient of 0.90. Contributions of the direct enzyme-ligand interaction energies, solvation energies and the long-range electrostatic interaction energies to the calculated binding energies were analyzed. The proton-transfer energies of the ligands with substituents ortho to the ionized OH were found to be perturbed less in the model calculations than the energies of their meta isomers as deduced from the corresponding pKas.
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Affiliation(s)
- M Peräkylä
- Department of Chemistry, University of Joensuu, Finland
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26
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Am1 and pm3 transition structure for the hydride transfer. A model of reaction catalyzed by dihydrofolate reductase. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0166-1280(94)03869-m] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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27
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Cummins PL, Gready JE. Computer-aided drug design: a free energy perturbation study on the binding of methyl-substituted pterins and N5-deazapterins to dihydrofolate reductase. J Comput Aided Mol Des 1993; 7:535-55. [PMID: 8294945 DOI: 10.1007/bf00124361] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Molecular dynamics simulation and free energy perturbation techniques have been used to study the relative binding free energies of 8-methylpterins and 8-methyl-N5-deazapterins to dihydrofolate reductase (DHFR). Methyl-substitution at the 5, 6 and 7 positions in the N-heterocyclic ring gives rise to a variety of ring substituent patterns and biological activity: several of these methyl derivatives of the 8-methyl parent compounds (8-methylpterin and 8-methyl-N5-deazapterin) have been identified as substrates or inhibitors of vertebrate DHFR in previous work. The calculated free energy differences reveal that the methyl-substituted compounds are thermodynamically more stable than the primary compounds (8-methylpterin and 8-methyl-N5-deazapterin) when bound to the enzyme, due largely to hydrophobic hydration phenomena. Methyl substitution at the 5 and/or 7 positions in the 6-methyl-substituted compounds has only a small effect on the stability of ligand binding. Furthermore, repulsive interactions between the 6-methyl substituent and DHFR are minimal, suggesting that the 6-methyl position is optimal for binding. The results also show that similarly substituted 8-methylpterins and 8-methyl-N5-deazapterins have very similar affinities for binding to DHFR. The computer simulation predictions are in broad agreement with experimental data obtained from kinetic studies, i.e. 6,8-dimethylpterin is a more efficient substrate than 8-methylpterin and 6,8-dimethyl-N5-deazapterin is a better inhibitor than 8-methyl-N5-deazapterin.
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Affiliation(s)
- P L Cummins
- Department of Biochemistry, University of Sydney, N.S.W., Australia
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28
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Cummins PL, Gready JE. Novel mechanism-based substrates of dihydrofolate reductase and the thermodynamics of ligand binding: a comparison of theory and experiment for 8-methylpterin and 6,8-dimethylpterin. Proteins 1993; 15:426-35. [PMID: 8460112 DOI: 10.1002/prot.340150409] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Molecular dynamics simulation and free energy perturbation techniques have been used to study the relative binding free energies of the designed mechanism-based pterins, 8-methylpterin and 6,8-dimethylpterin, to dihydrofolate reductase (DHFR), with cofactor nicotinamide adenine dinucleotide phosphate (NADPH). The calculated free energy differences suggest that DHFR.NADPH.6,8-dimethylpterin is thermodynamically more stable than DHFR.NADPH.8-methylpterin by 2.4 kcal/mol when the substrates are protonated and by 1.3 kcal/mol when neutral. The greater binding strength of 6,8-dimethylpterin may be attributed largely to hydration effects. In terms of an appropriate model for the pH-dependent kinetic mechanism, these differences can be interpreted consistently with experimental data obtained from previous kinetic studies, i.e., 6,8-dimethylpterin is a more efficient substrate of vertebrate DHFRs than 8-methylpterin. The kinetic data suggest a value of 6.6 +/- 0.2 for the pKa of the active site Glu-30 in DHFR.NADPH. We have also used experimental data to estimate absolute values for thermodynamic dissociation constants of the active (i.e., protonated) forms of the substrates: these are of the same order as for the binding of folate (0.1-10 microM). The relative binding free energy calculated from the empirically derived dissociation constants for the protonated forms of 8-methylpterin and 6,8-dimethylpterin is 1.4 kcal/mol, a value which compares reasonably well with the theoretical value of 2.4 kcal/mol.
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Affiliation(s)
- P L Cummins
- Department of Biochemistry, University of Sydney, N.S.W., Australia
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29
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Ivery MT, Gready JE. Comparison of binding and activity of 8-alkyl-pterins and 8-alkyl-N5-deaza-pterins with dihydrofolate reductase. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:525-8. [PMID: 8304172 DOI: 10.1007/978-1-4615-2960-6_106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- M T Ivery
- Department of Biochemistry, University of Sydney, NSW, Australia
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30
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Cummins PL, Gready JE. The effect of codon 31 on the relative affinities for the binding of designed 8-alkyl-pterins to dihydrofolate reductase: a statistical perturbation theory and molecular dynamics simulation study. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:511-4. [PMID: 8304169 DOI: 10.1007/978-1-4615-2960-6_103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- P L Cummins
- Department of Biochemistry, University of Sydney, N.S.W. Australia
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31
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Gready JE, Cummins PL, Wormell P. Computer-aided design of mechanism-based pterin analogues and MD/FEP simulations of their binding to dihydrofolate reductase. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:487-92. [PMID: 8304164 DOI: 10.1007/978-1-4615-2960-6_98] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Using a combined theoretical and experimental approach we have been able to predict several chemical properties and the contributions of the many factors which determine the macroscopic binding behaviour of these new mechanism-based compounds with DHFR, and also analyse experimental data to develop structure-activity relationships.
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Affiliation(s)
- J E Gready
- Department of Biochemistry, University of Sydney NSW, Australia
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