1
|
Mansour B, Gauld JW. Computational Insights into Amide Bond Formation Catalyzed by the Condensation Domain of Nonribosomal Peptide Synthetases. ACS OMEGA 2024; 9:28556-28563. [PMID: 38973878 PMCID: PMC11223147 DOI: 10.1021/acsomega.4c02531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 06/10/2024] [Accepted: 06/12/2024] [Indexed: 07/09/2024]
Abstract
Nonribosomal peptide synthetases (NRPSs) are important enzymes that synthesize an array of nongenetically encoded peptides. The latter have diverse physicochemical properties and roles. NRPSs are modular enzymes in which, for example, the condensation (C-) domain catalyzes the formation of amide bonds. The NRPS tyrocidine synthetase from Brevibacillus brevis is responsible for synthesizing the cyclic-peptide antibiotic tyrocidine. The first step is formation of an amide bond between a proline and phenylalanine which is catalyzed by a C-domain. In this study, a multiscale computational approach (molecular dynamics and QM/MM) has been used to investigate substrate binding and catalytic mechanism of the C-domain of tyrocidine synthetase. Overall, the mechanism is found to proceed through three exergonic steps in which an active site Histidine, His222, acts as a base and acid. First, His222 acts as a base to facilitate nucleophilic attack of the prolyl nitrogen at the phenylalanyl's carbonyl carbon. This is also the rate-limiting step with a free energy barrier of 38.8 kJ mol-1. The second step is collapse of the resulting tetrahedral intermediate with cleavage of the S-C bond between the phenylalanyl and its Ppant arm, along with formation of the above amide bond. Meanwhile, the now protonated His222 imidazole has rotated toward the newly formed thiolate of the Ppant arm. In the final step, His222 acts as an acid, protonating the thiolate and regenerating a neutral His222. The overall mechanism is found to be exergonic with the final product complex being 46.3 kJ mol-1 lower in energy than the initial reactant complex.
Collapse
Affiliation(s)
- Basel Mansour
- Department of Chemistry and
Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - James W. Gauld
- Department of Chemistry and
Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| |
Collapse
|
2
|
Kaur M, Kaur B, Kaur J, Kaur A, Bhatti R, Singh P. Role of water in cyclooxygenase catalysis and design of anti-inflammatory agents targeting two sites of the enzyme. Sci Rep 2020; 10:10764. [PMID: 32612190 PMCID: PMC7329864 DOI: 10.1038/s41598-020-67655-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/12/2020] [Indexed: 11/15/2022] Open
Abstract
While designing the anti-inflammatory agents targeting cyclooxygenase-2 (COX-2), we first identified a water loop around the heme playing critical role in the enzyme catalysis. The results of molecular dynamic studies supported by the strong hydrogen-bonding equilibria of the participating atoms, radical stabilization energies, the pKa of the H-donor/acceptor sites and the cyclooxygenase activity of pertinent muCOX-2 ravelled the working of the water–peptide channel for coordinating the flow of H·/electron between the heme and Y385. Based on the working of H·/electron transfer channel between the 12.5 Å distant radical generation and the radical disposal sites, a series of molecules was designed and synthesized. Among this category of compounds, an appreciably potent anti-inflammatory agent exhibiting IC50 0.06 μM against COX-2 and reversing the formalin induced analgesia and carageenan induced inflammation in mice by 90% was identified. Further it was revealed that, justifying its bidentate design, the compound targets water loop (heme bound site) and the arachidonic acid binding pockets of COX-2.
Collapse
Affiliation(s)
- Manpreet Kaur
- UGC Sponsored Centre for Advanced Studies, Department of Chemistry, Guru Nanak Dev University, Amritsar, 143005, India
| | - Baljit Kaur
- UGC Sponsored Centre for Advanced Studies, Department of Chemistry, Guru Nanak Dev University, Amritsar, 143005, India
| | - Jagroop Kaur
- UGC Sponsored Centre for Advanced Studies, Department of Chemistry, Guru Nanak Dev University, Amritsar, 143005, India
| | - Anudeep Kaur
- Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Rajbir Bhatti
- Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar, 143005, India
| | - Palwinder Singh
- UGC Sponsored Centre for Advanced Studies, Department of Chemistry, Guru Nanak Dev University, Amritsar, 143005, India.
| |
Collapse
|
3
|
Lenz SAP, Wetmore SD. QM/MM Study of the Reaction Catalyzed by Alkyladenine DNA Glycosylase: Examination of the Substrate Specificity of a DNA Repair Enzyme. J Phys Chem B 2017; 121:11096-11108. [PMID: 29148771 DOI: 10.1021/acs.jpcb.7b09646] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Human alkyladenine DNA glycosylase (AAG) functions as part of the base excision repair pathway to excise structurally diverse oxidized and alkylated DNA purines. Specifically, AAG uses a water molecule activated by a general base and a nonspecific active site lined with aromatic residues to cleave the N-glycosidic bond. Despite broad substrate specificity, AAG does not target the natural purines (adenine (A) and guanine (G)). Using the ONIOM(QM:MM) methodology, we provide fundamental atomic level details of AAG bound to DNA-containing a neutral substrate (hypoxanthine (Hx)), a nonsubstrate (G), or a cationic substrate (7-methylguanine (7MeG)) and probe changes in the reaction pathway that occur when AAG targets different nucleotides. We reveal that subtle differences in protein-DNA contacts upon binding different substrates within the flexible AAG active site can significantly affect the deglycosylation reaction. Notably, we predict that AAG excises Hx in a concerted mechanism that is facilitated through correct alignment of the (E125) general base due to hydrogen bonding with a neighboring aromatic amino acid (Y127). Hx departure is further stabilized by π-π interactions with aromatic amino acids and hydrogen bonds with active site water. Despite possessing a similar structure to Hx, G is not excised since the additional exocyclic amino group leads to misalignment of the general base due to disruption of the key E125-Y127 hydrogen bond, the catalytically unfavorable placement of water within the active site, and weakened π-contacts between aromatic amino acids and the nucleobase. In contrast, cationic 7MeG does not occupy the same position within the AAG active site as G due to steric clashes with the additional N7 methyl group, which results in the correct alignment of the general base and permits nucleobase excision as observed for neutral Hx. Overall, our structural data rationalizes the observed substrate specificity of AAG and contributes to our fundamental understanding of enzymes with flexible active sites and broad substrate specificities.
Collapse
Affiliation(s)
- Stefan A P Lenz
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| |
Collapse
|
4
|
Khavani M, Izadyar M. Implicit and explicit solvent effects on the selectivity of the cycloaddition reaction of cyclopentadiene and methyl acrylate; a theoretical study. PROGRESS IN REACTION KINETICS AND MECHANISM 2015. [DOI: 10.3184/146867815x14297104685269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The product selectivity of the Diels–Alder reaction between cyclopentadiene and methyl acrylate has been studied through a solvent effect analysis by implicit and explicit solvent models. Two paths for this reaction have been proposed and thermodynamic and kinetic parameters for each path were calculated by the B3LYP functional with 6-311++G(d,p) basis set at 298.15 K. In the explicit solvent model, hydrogen bonds were investigated by the QM/MM method. According to the results, the proportion of the exo product in the gas phase is more than for the endo one, which is in contrast to the solvent phase. HOMO–LUMO analyses in the gas phase and different solvents have been done and solvent effects on the energies of the HOMO–LUMO orbitals were investigated. According to the results, the band gap of the TSs was increased in the presence of the solvents. Finally, natural population analysis has been performed to calculate the electronic charges of some atoms that are involved in the centre of the reaction. The data obtained showed that different solvents, including polar and nonpolar solvents, have different effects on the electronic charges of the atoms. Topological analysis of the structures during the reaction by the quantum theory of atoms in molecules (QTAIM) method in the gas phase and different solvents confirmed a cyclic structure for the transition state.
Collapse
Affiliation(s)
- Mohammad Khavani
- Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Mohammad Izadyar
- Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| |
Collapse
|
5
|
Chung LW, Sameera WMC, Ramozzi R, Page AJ, Hatanaka M, Petrova GP, Harris TV, Li X, Ke Z, Liu F, Li HB, Ding L, Morokuma K. The ONIOM Method and Its Applications. Chem Rev 2015; 115:5678-796. [PMID: 25853797 DOI: 10.1021/cr5004419] [Citation(s) in RCA: 760] [Impact Index Per Article: 84.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Lung Wa Chung
- †Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, China
| | - W M C Sameera
- ‡Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan
| | - Romain Ramozzi
- ‡Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan
| | - Alister J Page
- §Newcastle Institute for Energy and Resources, The University of Newcastle, Callaghan 2308, Australia
| | - Miho Hatanaka
- ‡Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan
| | - Galina P Petrova
- ∥Faculty of Chemistry and Pharmacy, University of Sofia, Bulgaria Boulevard James Bourchier 1, 1164 Sofia, Bulgaria
| | - Travis V Harris
- ‡Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan.,⊥Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, United States
| | - Xin Li
- #State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Zhuofeng Ke
- ∇School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Fengyi Liu
- ○Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Hai-Bei Li
- ■School of Ocean, Shandong University, Weihai 264209, China
| | - Lina Ding
- ▲School of Pharmaceutical Sciences, Zhengzhou University, 100 Kexue Avenue, Zhengzhou, Henan 450001, China
| | - Keiji Morokuma
- ‡Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan
| |
Collapse
|
6
|
Dutta A, Bhattacharyya S, Dutta D, Das AK. Structural elucidation of the binding site and mode of inhibition of Li+and Mg2+in inositol monophosphatase. FEBS J 2014; 281:5309-24. [PMID: 25263816 DOI: 10.1111/febs.13070] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/16/2014] [Accepted: 09/23/2014] [Indexed: 01/20/2023]
Affiliation(s)
- Anirudha Dutta
- Department of Biotechnology; Indian Institute of Technology Kharagpur; Kharagpur West Bengal India
| | - Sudipta Bhattacharyya
- Department of Biotechnology; Indian Institute of Technology Kharagpur; Kharagpur West Bengal India
| | - Debajyoti Dutta
- Department of Biotechnology; Indian Institute of Technology Kharagpur; Kharagpur West Bengal India
| | - Amit Kumar Das
- Department of Biotechnology; Indian Institute of Technology Kharagpur; Kharagpur West Bengal India
| |
Collapse
|
7
|
Zhang Y, Yan S, Yao L. A Mechanistic Study of Trichoderma reesei Cel7B Catalyzed Glycosidic Bond Cleavage. J Phys Chem B 2013; 117:8714-22. [DOI: 10.1021/jp403999s] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Yu Zhang
- Laboratory
of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Shihai Yan
- Laboratory
of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Lishan Yao
- Laboratory
of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| |
Collapse
|