1
|
Diao W, Farrell JD, Wang B, Ye F, Wang Z. Preorganized Internal Electric Field Promotes a Double-Displacement Mechanism for the Adenine Excision Reaction by Adenine DNA Glycosylase. J Phys Chem B 2023; 127:8551-8564. [PMID: 37782825 DOI: 10.1021/acs.jpcb.3c04928] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Adenine DNA glycosylase (MutY) is a monofunctional glycosylase, removing adenines (A) misinserted opposite 8-oxo-7,8-dihydroguanine (OG), a common product of oxidative damage to DNA. Through multiscale calculations, we decipher a detailed adenine excision mechanism of MutY that is consistent with all available experimental data, involving an initial protonation step and two nucleophilic displacement steps. During the first displacement step, N-glycosidic bond cleavage is accompanied by the attack of the carboxylate group of residue Asp144 at the anomeric carbon (C1'), forming a covalent glycosyl-enzyme intermediate to stabilize the fleeting oxocarbenium ion. After departure of the excised base, water nucleophiles can be recruited to displace Asp144, completing the catalytic cycle with retention of stereochemistry at the C1' position. The two displacement reactions are found to mostly involve the movement of the oxocarbenium ion, occurring with large charge reorganization and thus sensitive to the internal electric field (IEF) exerted by the polar protein environment. Intriguingly, we find that the negatively charged carboxylate group is a good nucleophile for the oxocarbenium ion, yet an unactivated water molecule is not, and that the electric field catalysis strategy is used by the enzyme to enable its unique double-displacement reaction mechanism. A strong IEF, pointing toward 5' direction of the substrate sugar ring, greatly facilitates the second displacement reaction at the expense of elevating the barrier of the first one, thereby allowing both reactions to occur. These findings not only increase our understanding of the strategies used by DNA glycosylases to repair DNA lesions, but also have important implications for how internal/external electric field can be applied to modulate chemical reactions.
Collapse
Affiliation(s)
- Wenwen Diao
- Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325000, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - James D Farrell
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Fangfu Ye
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325000, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, Zhejiang 325000, China
| | - Zhanfeng Wang
- Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China
| |
Collapse
|
2
|
Diao W, Yan S, Farrell JD, Wang B, Ye F, Wang Z. Preorganized Internal Electric Field Powers Catalysis in the Active Site of Uracil-DNA Glycosylase. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wenwen Diao
- Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325000, China
| | - Shengheng Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - James D. Farrell
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Fangfu Ye
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang 325000, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, Zhejiang 325001, China
| | - Zhanfeng Wang
- Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China
| |
Collapse
|
3
|
Jiang Y, Xue Y, Zeng Y. Microsolvated Model for the Kinetics and Thermodynamics of Glycosidic Bond Dissociative Cleavage of Nucleoside D4G. J Phys Chem B 2018; 122:1816-1825. [PMID: 29316403 DOI: 10.1021/acs.jpcb.7b11331] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using the microsolvated model that involves explicit water molecules and implicit solvent in the optimization, two proposed dissociative hydrolysis mechanisms of 2',3'-didehydro-2',3'-dideoxyguanosine (d4G) have been first investigated by means of M06-2X(CPCM, water)/6-31++G(d,p) method. The glycosidic bond dissociation for the generation of the oxacarbenium ion intermediate is the rate-determining step (RDS). The subsequent nucleophilic water attack from different side of the oxacarbenium ion intermediate gives either the α-product [(2S,5S)-5-(hydroxymethyl)-2,5-dihydrofuran-2-ol] or β-product [(2R,5S)-5-(hydroxymethyl)-2,5-dihydrofuran-2-ol] and is thus referred to as α-path (inversion) and β-path (retention). Two to five explicit water molecules (n = 2-5) are considered in the microsolvated model, and n = 3 or 4 is the smallest model capable of minimizing the activation energy for α-path and β-path, respectively. Our theoretical results suggest that α-path (n = 3) is more kinetically favorable with lower free energy barrier (RDS) of 27.7 kcal mol-1, in contrast to that of 30.7 kcal mol-1 for the β-path (n = 4). The kinetic preference of the α-path is rationalized by NBO analysis. Whereas thte β-path is more thermodynamically favorable over the α-path, where the formation of β-product and α-product are exergonic and endergonic, respectively, providing theoretical support for the experimental observation that the β-cleavage product was the major one after sufficient reaction time. Comparisons of d4G with analogous cyclo-d4G and dG from kinetic free energy barriers and thermodynamic heterolytic dissociation energies were also carried out. Our kinetic and thermodynamic results manifest that the order of glycosidic bond stability should be d4G < cyclo-d4G < dG, which agrees well with the reported experimental stability order of d4G compounds and analogues and gives further understanding on the influence of 6-cyclopropylamino and unsaturated ribose to the glycosidic bond instability of d4G.
Collapse
Affiliation(s)
- Yang Jiang
- College of Pharmacy and Biological Engineering, Chengdu University , Chengdu 610106, China
| | - Ying Xue
- Key Laboratory of Green Chemistry and Technology in Ministry of Education, College of Chemistry, Sichuan University , Chengdu 610064, China
| | - Yi Zeng
- School of Science, Xihua University , Chengdu 610039, China
| |
Collapse
|
4
|
Fan F, Chen N, Wang Y, Wu R, Cao Z. QM/MM and MM MD Simulations on the Pyrimidine-Specific Nucleoside Hydrolase: A Comprehensive Understanding of Enzymatic Hydrolysis of Uridine. J Phys Chem B 2018; 122:1121-1131. [PMID: 29285933 DOI: 10.1021/acs.jpcb.7b10524] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The pyrimidine-specific nucleoside hydrolase Yeik (CU-NH) from Escherichia coli cleaves the N-glycosidic bond of uridine and cytidine with a 102-104-fold faster rate than that of purine nucleoside substrates, such as inosine. Such a remarkable substrate specificity and the plausible hydrolytic mechanisms of uridine have been explored by using QM/MM and MM MD simulations. The present calculations show that the relatively stronger hydrogen-bond interactions between uridine and the active-site residues Gln227 and Tyr231 in CU-NH play an important role in enhancing the substrate binding and thus promoting the N-glycosidic bond cleavage, in comparison with inosine. The estimated energy barrier of 30 kcal/mol for the hydrolysis of inosine is much higher than 22 kcal/mol for uridine. Extensive MM MD simulations on the transportation of substrates to the active site of CU-NH indicate that the uridine binding is exothermic by ∼23 kcal/mol, more remarkable than inosine (∼12 kcal/mol). All of these arise from the noncovalent interactions between the substrate and the active site featured in CU-NH, which account for the substrate specificity. Quite differing from other nucleoside hydrolases, here the enzymatic N-glycosidic bond cleavage of uridine is less influenced by its protonation.
Collapse
Affiliation(s)
- Fangfang Fan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 360015, China
| | - Nanhao Chen
- Department of Chemistry, University of California , Davis, California 95616, United States
| | - Yongheng Wang
- School of Pharmaceutical Sciences, Sun Yat-sen University , Guangzhou 510006, China
| | - Ruibo Wu
- School of Pharmaceutical Sciences, Sun Yat-sen University , Guangzhou 510006, China
| | - Zexing Cao
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 360015, China
| |
Collapse
|
5
|
Lenz SAP, Kohout JD, Wetmore SD. Hydrolytic Glycosidic Bond Cleavage in RNA Nucleosides: Effects of the 2'-Hydroxy Group and Acid-Base Catalysis. J Phys Chem B 2016; 120:12795-12806. [PMID: 27933981 DOI: 10.1021/acs.jpcb.6b09620] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Despite the inherent stability of glycosidic linkages in nucleic acids that connect the nucleobases to sugar-phosphate backbones, cleavage of these bonds is often essential for organism survival. The current study uses DFT (B3LYP) to provide a fundamental understanding of the hydrolytic deglycosylation of the natural RNA nucleosides (A, C, G, and U), offers a comparison to DNA hydrolysis, and examines the effects of acid, base, or simultaneous acid-base catalysis on RNA deglycosylation. By initially examining HCOO-···H2O mediated deglycosylation, the barriers for RNA hydrolysis were determined to be 30-38 kJ mol-1 higher than the corresponding DNA barriers, indicating that the 2'-OH group stabilizes the glycosidic bond. Although the presence of HCOO- as the base (i.e., to activate the water nucleophile) reduces the barrier for uncatalyzed RNA hydrolysis (i.e., unactivated H2O nucleophile) by ∼15-20 kJ mol-1, the extreme of base catalysis as modeled using a fully deprotonated water molecule (i.e., OH- nucleophile) decreases the uncatalyzed barriers by up to 65 kJ mol-1. Acid catalysis was subsequently examined by selectively protonating the hydrogen-bond acceptor sites of the RNA nucleobases, which results in an up to ∼80 kJ mol-1 barrier reduction relative to the corresponding uncatalyzed pathway. Interestingly, the nucleobase proton acceptor sites that result in the greatest barrier reductions match sites typically targeted in enzyme-catalyzed reactions. Nevertheless, simultaneous acid and base catalysis is the most beneficial way to enhance the reactivity of the glycosidic bonds in RNA, with the individual effects of each catalytic approach being weakened, additive, or synergistic depending on the strength of the base (i.e., degree of water nucleophile activation), the nucleobase, and the hydrogen-bonding acceptor site on the nucleobase. Together, the current contribution provides a greater understanding of the reactivity of the glycosidic bond in natural RNA nucleosides, and has fundamental implications for the function of RNA-targeting enzymes.
Collapse
Affiliation(s)
- Stefan A P Lenz
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Johnathan D Kohout
- 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
|
6
|
Wu RR, Chen Y, Rodgers MT. Mechanisms and energetics for N-glycosidic bond cleavage of protonated 2'-deoxyguanosine and guanosine. Phys Chem Chem Phys 2016; 18:2968-80. [PMID: 26740232 DOI: 10.1039/c5cp05738h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Experimental and theoretical investigations suggest that hydrolysis of N-glycosidic bonds generally involves a concerted SN2 or a stepwise SN1 mechanism. While theoretical investigations have provided estimates for the intrinsic activation energies associated with N-glycosidic bond cleavage reactions, experimental measurements to validate the theoretical studies remain elusive. Here we report experimental investigations for N-glycosidic bond cleavage of the protonated guanine nucleosides, [dGuo+H](+) and [Guo+H](+), using threshold collision-induced dissociation (TCID) techniques. Two major dissociation pathways involving N-glycosidic bond cleavage, resulting in production of protonated guanine or the elimination of neutral guanine are observed in competition for both [dGuo+H](+) and [Guo+H](+). The detailed mechanistic pathways for the N-glycosidic bond cleavage reactions observed are mapped via electronic structure calculations. Excellent agreement between the measured and B3LYP calculated activation energies and reaction enthalpies for N-glycosidic bond cleavage of [dGuo+H](+) and [Guo+H](+) in the gas phase is found indicating that these dissociation pathways involve stepwise E1 mechanisms in analogy to the SN1 mechanisms that occur in the condensed phase. In contrast, MP2 is found to significantly overestimate the activation energies and slightly overestimate the reaction enthalpies. The 2'-hydroxyl substituent is found to stabilize the N-glycosidic bond such that [Guo+H](+) requires ∼25 kJ mol(-1) more than [dGuo+H](+) to activate the glycosidic bond.
Collapse
Affiliation(s)
- R R Wu
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - Yu Chen
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| | - M T Rodgers
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
| |
Collapse
|
7
|
Lenz SAP, Kellie JL, Wetmore SD. Glycosidic Bond Cleavage in DNA Nucleosides: Effect of Nucleobase Damage and Activation on the Mechanism and Barrier. J Phys Chem B 2015; 119:15601-12. [PMID: 26618397 DOI: 10.1021/acs.jpcb.5b10337] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stefan A. P. Lenz
- Department of Chemistry and
Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Jennifer L. Kellie
- 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
|
8
|
Tian Y, Fu J, Zhang Y, Cao K, Bai C, Wang D, Li S, Xue Y, Ma L, Zheng C. Ligand-exchange mechanism: new insight into solid-phase extraction of uranium based on a combined experimental and theoretical study. Phys Chem Chem Phys 2015; 17:7214-23. [DOI: 10.1039/c4cp05508j] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The extraction mechanism is an exchange process between the ligands on Urea-GO and the coordinated water molecules of uranyl.
Collapse
Affiliation(s)
- Yin Tian
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
- College of Physical Science and Technology
| | - Jia Fu
- College of Physical Science and Technology
- Sichuan University
- Chengdu 610064
- People's Republic of China
| | - Yi Zhang
- College of Physical Science and Technology
- Sichuan University
- Chengdu 610064
- People's Republic of China
| | - Kecheng Cao
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
| | - Chiyao Bai
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
| | - Dongqi Wang
- CAS Key Laboratory of Nuclear Radiation and Nuclear Energy Techniques
- and Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing
- China
| | - Shoujian Li
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
| | - Ying Xue
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
| | - Lijian Ma
- College of Chemistry
- Sichuan University
- Chengdu
- People's Republic of China
| | - Chong Zheng
- Department of Chemistry and Biochemistry
- Northern Illinois University
- DeKalb
- USA
| |
Collapse
|
9
|
Chen Z, Zeng B, Tao J, Kang Y, Xue Y. A theoretical exploration of the photoinduced reductive repair mechanisms of thymidine glycol. J Photochem Photobiol A Chem 2014. [DOI: 10.1016/j.jphotochem.2014.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
10
|
The effect of intramolecular hydrogen bond on the N-glycosidic bond strength in 3-methyl-2′-deoxyadenosine: a quantum chemical study. Struct Chem 2014. [DOI: 10.1007/s11224-014-0493-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
11
|
Gökcan H, Konuklar FAS. Stereoelectronic explanations for the mechanistic details of transimination and HF elimination reactions. J Mol Graph Model 2014; 51:173-83. [PMID: 24929816 DOI: 10.1016/j.jmgm.2014.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 05/21/2014] [Accepted: 05/22/2014] [Indexed: 11/26/2022]
Abstract
The β-fluoroamines are commonly used as substrate analogs to determine the mechanistic details of enzymatic reactions. Presence of fluorine atom gives rise to the alterations in the electronic profile and the pKa of molecules which results in mechanistic deviations. The fluorine-substituted mechanism-based substrate analogs are widely used in the inactivation of pyridoxal 5'-phosphate (PLP)-dependent enzymes. The presence of fluorine atom also alters the sequence of reactions taking place in PLP-dependent enzymes where the HF elimination reaction appears in between the transimination and inactivation reactions. Despite the amount of the works on β-fluoroamines, the effect of stereoelectronic differences on the transimination and HF elimination reactions taking place in PLP-dependent enzymes has not been investigated yet. A density functional theory study is conducted to elucidate mechanistic details of the reactions occurring in PLP-dependent enzymes. In order to understand the mechanistic insights of different isomers and the effect of the fluorine atom, 4-amino-3-fluorobutanoic acid (3-F-GABA) enantiomers are chosen to be investigated besides 4-aminobutanoic acid (GABA), which is the natural substrate for γ-aminobutyric acid aminotransferase (GABA-AT). The investigated β-fluoroamines are the experimentally proposed potential inhibitors of PLP-dependent enzyme GABA-AT.
Collapse
Affiliation(s)
- Hatice Gökcan
- Istanbul Technical University, Informatics Institute, Computational Science and Engineering Division, Ayazağa Campus, 34496 Maslak, Istanbul, Turkey
| | - F Aylin Sungur Konuklar
- Istanbul Technical University, Informatics Institute, Computational Science and Engineering Division, Ayazağa Campus, 34496 Maslak, Istanbul, Turkey.
| |
Collapse
|
12
|
Stimulation of N--glycoside transfer in deoxythymidine glycol: mechanism of the initial step in base excision repair. J Mol Model 2014; 20:2168. [PMID: 24595719 DOI: 10.1007/s00894-014-2168-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 02/04/2014] [Indexed: 10/25/2022]
Abstract
Thymine glycol (Tg), a toxic oxidative DNA lesion, is preferentially removed by endonuclease III (Endo III). To investigate the glycosylase activity of Endo III, the N--glycoside transfer mechanism in deoxythymidine glycol (dTg) is examined in this theoretical study based on the BHandHLYP/6-311++G(d,p) level of theory. Two controversial mechanisms were characterized, i.e., the displacement and endocyclic mechanisms. For each mechanism, three types of reaction models were established, including the direct reaction, local microhydration and protonated models. The calculated results indicate that (i) all three reaction models favor the displacement mechanism more than the endocyclic mechanism; (ii) the local microhydration model allows for discrete proton transfer and contributes to the reduction of activation energies, nevertheless, large activation energies are still involved; (iii) the O4'-protonated endocyclic model can efficiently promote the nucleophilic attack of lysine residue and an amino acid residue other than the nucleophilic lysine should be responsible for the opening of the sugar ring; (iv) the O2-protonated displacement model facilitates the leaving group (Tg) stabilization and therefore is the preferred mechanism for the N--glycoside transfer of dTg, whose activation energy of 17.7 kcal mol⁻¹ is in good agreement with the experimental estimate of 19.0 kcal mol⁻¹. As a result, the protonation of nucleobase plays a significant role in predicting the preferred glycosylase mechanism. Our findings can propose appropriate mechanisms for future large-scale enzymatic modeling of Endo III and provide more fundamental information about the important residues that may be included in the enzyme-catalyzed reactions.
Collapse
|
13
|
Navarro-Whyte L, Kellie JL, Lenz SAP, Wetmore SD. Hydrolysis of the damaged deoxythymidine glycol nucleoside and comparison to canonical DNA. Phys Chem Chem Phys 2013; 15:19343-52. [DOI: 10.1039/c3cp53217h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
14
|
Lenz SAP, Kellie JL, Wetmore SD. Glycosidic bond cleavage in deoxynucleotides: effects of solvent and the DNA phosphate backbone in the computational model. J Phys Chem B 2012; 116:14275-84. [PMID: 23167947 DOI: 10.1021/jp3096677] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Density functional theory (B3LYP) was employed to examine the hydrolysis of the canonical 2'-deoxynucleotides in varied environments (gas phase or water) using different computational models for the sugar residue (methyl or phosphate group at C5') and nucleophile (water activated through full or partial proton abstraction). Regardless of the degree of nucleophile activation, our results show that key geometrical parameters along the reaction pathway are notably altered upon direct inclusion of solvent effects in the optimization routine, which leads to significant changes in the reaction energetics and better agreement with experiment. Therefore, despite the wide use of gas-phase calculations in the literature, small model computational work, as well as large-scale enzyme models, that strive to understand nucleotide deglycosylation must adequately describe the environment. Alternatively, although inclusion of the phosphate group at C5' also affects the geometries of important stationary points, the effects cancel to yield unchanged deglycosylation barriers, and therefore smaller computational models can be used to estimate the energy associated with nucleotide deglycosylation, with the 5' phosphate group included if full (geometric) details of the reaction are desired. Hydrogen-bonding interactions with the nucleobase can significantly reduce the barrier to deglycosylation, which supports suggestions that discrete hydrogen-bonding interactions with active-site amino acid residues can play a significant role in enzyme-catalyzed nucleobase excision. Taken together with previous studies, the present work provides vital clues about the components that must be included in future studies of the deglycosylation of isolated noncanonical nucleotides, as well as the corresponding enzyme-catalyzed reactions.
Collapse
Affiliation(s)
- Stefan A P Lenz
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive West, Lethbridge, Alberta, Canada T1K 3M4
| | | | | |
Collapse
|
15
|
Šebera J, Trantírek L, Tanaka Y, Sychrovský V. Pyramidalization of the glycosidic nitrogen provides the way for efficient cleavage of the N-glycosidic bond of 8-OxoG with the hOGG1 DNA repair protein. J Phys Chem B 2012; 116:12535-44. [PMID: 22989268 DOI: 10.1021/jp309098d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A mechanistic pathway for cleavage of the N-glycosidic bond of 8-oxo-2'-deoxyguanosine (oxoG) catalyzed with the human 8-oxoguanine glycosylase 1 DNA repair protein (hOGG1) is proposed in this theoretical study. The reaction scheme suggests direct proton addition to the glycosidic nitrogen N9 of oxoG from the Nε-ammonium of Lys249 residue of hOGG1 that is enabled owing to the N9 pyramidal geometry. The N9-pyramidalization of oxoG is induced within hOGG1 active site. The coordination of N9 nitrogen to the Nε-ammonium of Lys249 unveiled by available crystal structures enables concerted, synchronous substitution of the N9-C1' bond by the N9-H bond. The reaction is compared with other pathways already proposed by means of calculated activation energies. The ΔG(#) energy for the newly proposed reaction mechanism calculated with the B3LYP/6-31G(d,p) method 17.0 kcal mol(-1) is significantly lower than ΔG(#) energies for other reactions employing attack of the Nε-amino group to the anomeric carbon C1' of oxoG and attack of the Nε-ammonium to the N3 nitrogen of oxoG base. Moreover, activation energy for the oxoG cleavage proceeding via N9-pyramidalization is lower than energy calculated for normal G because the electronic state of the five-membered aromatic ring of oxoG is better suited for the reaction. The modification of aromatic character introduced by oxidation to the nucleobase thus seems to be the factor that is checked by hOGG1 to achieve base-specific cleavage.
Collapse
Affiliation(s)
- Jakub Šebera
- Institute of Organic Chemistry and Biochemistry AS CR, v.v.i., Flemingovo náměstí 2, CZ, 16610 Praha, Czech Republic
| | | | | | | |
Collapse
|
16
|
Kellie JL, Navarro-Whyte L, Carvey MT, Wetmore SD. Combined effects of π-π stacking and hydrogen bonding on the (N1) acidity of uracil and hydrolysis of 2'-deoxyuridine. J Phys Chem B 2012; 116:2622-32. [PMID: 22296509 DOI: 10.1021/jp2121627] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
M06-2X/6-31+G(d,p) is used to study the simultaneous effects of π-π stacking interactions with phenylalanine (modeled as benzene) and hydrogen bonding with small molecules (HF, H(2)O, and NH(3)) on the N1 acidity of uracil and the hydrolytic deglycosylation of 2'-deoxyuridine (dU) (facilitated by fully (OH(-)) or partially (HCOO(-)···H(2)O) activated water). When phenylalanine is complexed with isolated uracil, the proton affinity of all acceptor sites significantly increases (by up to 28 kJ mol(-1)), while the N1 acidity slightly decreases (by ~6 kJ mol(-1)). When small molecules are hydrogen bound to uracil, addition of the phenylalanine ring can increase or decrease the acidity of uracil depending on the number and nature (acidity) of the molecules bound. Furthermore, a strong correlation between the effects of π-π stacking on the acidity of U and the dU deglycosylation reaction energetics is found, where the hydrolysis barrier can increase or decrease depending on the nature and number of small molecules bound, the nucleophile considered (which dictates the negative charge on U in the transition state), and the polarity of the (bulk) environment. These findings emphasize that the catalytic (or anticatalytic) role of the active-site aromatic amino acid residues is highly dependent on the situation under consideration. In the case of uracil-DNA glycosylase (UNG), which catalyzes the hydrolytic excision of uracil from DNA, the type of discrete hydrogen-bonding interactions with U, the nature of the nucleophile, and the anticipated weak, nonpolar environment in the active site suggest that phenylalanine will be slightly anticatalytic in the chemical step, and therefore experimentally observed contributions to catalysis may entirely result from associated structural changes that occur prior to deglycosylation.
Collapse
Affiliation(s)
- Jennifer L Kellie
- Department of Chemistry & Biochemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta T1K 3M4, Canada
| | | | | | | |
Collapse
|
17
|
Wu R, Gong W, Liu T, Zhang Y, Cao Z. QM/MM Molecular Dynamics Study of Purine-Specific Nucleoside Hydrolase. J Phys Chem B 2012; 116:1984-91. [DOI: 10.1021/jp211403j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Ruibo Wu
- School of
Pharmaceutical Sciences,
East Campus, Sun Yat-sen University, Guangzhou
510006, China
- State Key
Laboratory of Physical
Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of
Theoretical and Computational Chemistry, College of Chemistry and
Chemical Engineering, Xiamen University, Xiamen 361005, China
- Department
of Chemistry, New York University, New
York, New York 10003, United
States
| | - Wengjin Gong
- Department
of Chemistry, New York University, New
York, New York 10003, United
States
| | - Ting, Liu
- State Key
Laboratory of Physical
Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of
Theoretical and Computational Chemistry, College of Chemistry and
Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yingkai Zhang
- Department
of Chemistry, New York University, New
York, New York 10003, United
States
| | - Zexing Cao
- State Key
Laboratory of Physical
Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of
Theoretical and Computational Chemistry, College of Chemistry and
Chemical Engineering, Xiamen University, Xiamen 361005, China
| |
Collapse
|
18
|
Zeng Y, Xue Y, Yan G. Substituent Effect on the Acid-Promoted Hydrolysis of 2-Aryloxazolin-5-one: Normal vs Reverse. J Phys Chem A 2011; 115:4995-5004. [DOI: 10.1021/jp200685g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yi Zeng
- School of Physics and Chemistry, Research Center for Advanced Computation, Xihua University, Chengdu 610039, People's Republic of China
| | - Ying Xue
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, People's Republic of China
| | - Guosen Yan
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, People's Republic of China
| |
Collapse
|
19
|
Chen ZQ, Zhang CH, Kim CK, Xue Y. Quantum mechanics study and Monte Carlo simulation on the hydrolytic deamination of 5-methylcytosine glycol. Phys Chem Chem Phys 2011; 13:6471-83. [PMID: 21380473 DOI: 10.1039/c0cp02783a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The efficient formation of 5-methylcytosine glycol (mCg) and its facile deamination to thymine glycol (Tg) may account for the prevalent C → T transition mutation found at methylated CpG site (mCpG) in human p53 gene, a hallmark for many types of human tumors. In this work, the hydrolytic deamination of mCg was investigated at the MP2 and B3LYP levels of theory using the 6-311G(d,p) basis set. In the gas phase, three pathways were explored, paths A-C, and it indicates that the direct deamination of mCg with H(2)O by either pathway is unlikely because of the high activation free energies involved in the rate-determining steps, the formation of the tetrahedral intermediate for paths A and B as well as the formation of the Tg tautomer for path C. In aqueous solution, the role of the water molecules in the deamination of mCg with H(2)O was analyzed in two separate parts: the direct participation of one water molecule in the reaction pathway, called the water-assisted mechanism; and the complementary participation of the aqueous solvation. The water-assisted mechanism was carried out for mCg and the cluster of two water molecules by quantum mechanical calculations in the gas phase. This indicates that the presence of the auxiliary water molecule significantly contributes to decreasing all the activation free energies. The bulk solution effect on the water-assisted mechanism was included by free energy perturbation implemented on Monte Carlo simulations, which is found to be substantial and decisive in the deamination mechanism of mCg. In this case, the water-assisted path A is the most plausible mechanism reported for the deamination of mCg, where the calculated activation free energy (22.6 kcal mol(-1) at B3LYP level of theory) agrees well with the experimentally determined activation free energy (24.8 kcal mol(-1)). The main striking results of the present DFT computational study which is in agreement with previous experimental data is the higher rate of deamination displayed by mCg residues with respect to 5-methylcytosine (mC) bases, which supports that the deamination of mCg contributes significantly to the C → T transition mutation at mCpG dinucleotide site.
Collapse
Affiliation(s)
- Ze Qin Chen
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, People's Republic of China
| | | | | | | |
Collapse
|
20
|
Ebrahimi A, Habibi-Khorassani M, Bazzi S. The impact of protonation and deprotonation of 3-methyl-2′-deoxyadenosine on N-glycosidic bond cleavage. Phys Chem Chem Phys 2011; 13:3334-43. [DOI: 10.1039/c0cp01279c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
21
|
Šponer JE, Šponer J, Fuentes-Cabrera M. Prebiotic Routes to Nucleosides: A Quantum Chemical Insight into the Energetics of the Multistep Reaction Pathways. Chemistry 2010; 17:847-54. [DOI: 10.1002/chem.201002057] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 09/02/2010] [Indexed: 11/11/2022]
|
22
|
On the mechanism of the N-glycosydic bond hydrolysis of 2′-deoxyguanosine: insights from first principles calculations. Theor Chem Acc 2010. [DOI: 10.1007/s00214-010-0826-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
23
|
Chen ZQ, Xue Y. Theoretical Investigations on the Thermal Decomposition Mechanism of 5-Hydroxy-6-hydroperoxy-5,6-dihydrothymidine in Water. J Phys Chem B 2010; 114:12641-54. [PMID: 20839840 DOI: 10.1021/jp100933d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Ze-qin Chen
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, P. R. China, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, P. R. China, and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, P. R. China
| | - Ying Xue
- College of Chemistry, Key Laboratory of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, P. R. China, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, P. R. China, and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, P. R. China
| |
Collapse
|
24
|
Shim EJ, Przybylski JL, Wetmore SD. Effects of nucleophile, oxidative damage, and nucleobase orientation on the glycosidic bond cleavage in deoxyguanosine. J Phys Chem B 2010; 114:2319-26. [PMID: 20095611 DOI: 10.1021/jp9113656] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deglycosylation of nucleotides occurs during many essential biological processes, including DNA repair, and is initiated by a variety of nucleophiles. In the present work, density functional theory (B3LYP) was used to investigate the thermodynamics and kinetics of the glycosidic bond cleavage reaction in the model nucleoside forms of guanine and its major oxidation product, 8-oxoguanine. Base excision facilitated by four different nucleophiles (hydroxyl anion (fully activated water), formate-water complex (partially activated water), lysine, and proline) was considered, which spans nucleophiles involved in a collection of spontaneous and enzyme-catalyzed processes. Because some enzymes that catalyze deglycosylation can accommodate more than one orientation of the base with respect to the sugar moiety, the effects of the (anti/syn) base orientation on the barrier height were also considered. We find that the nucleophile has a very large effect on the overall (gas-phase) reaction energetics. Although this effect decreases in different (polar) environments, the nucleophile has the greatest influence on the overall reaction as compared to whether the base is damaged or to the base orientation. Furthermore, the effects are significant in environments that most closely resemble (nonpolar) enzymatic active sites. Our results provide a greater understanding of the relative effects of the nucleophile, damage to the nucleobase, and the nucleobase orientation with respect to the sugar moiety on the deglycosylation pathway, which provide qualitative explanations for relative base excision rates observed in some biological systems.
Collapse
Affiliation(s)
- Eun Jung Shim
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta T1K 3M4, Canada
| | | | | |
Collapse
|
25
|
Przybylski JL, Wetmore SD. Modeling the dissociative hydrolysis of the natural DNA nucleosides. J Phys Chem B 2010; 114:1104-13. [PMID: 20039632 DOI: 10.1021/jp9098717] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two-dimensional PCM-B3LYP/6-31+G(d) potential energy surfaces for the hydrolysis of the four natural 2'-deoxyribonucleosides (2'-deoxyadenosine, 2'-deoxyguanosine, 2'-deoxycytidine, and thymidine) are characterized using a model that includes both implicit (bulk) solvent effects and (three or four) explicit water molecules in the optimization routine. For the first time, the experimentally predicted dissociative (S(N)1) mechanism is found to be favored over the synchronous (S(N)2) pathway for all nucleosides studied. Due to the success of our model in stabilizing the charge-separated intermediates along the S(N)1 pathway, it is proposed that the new model presented here is the smallest system capable of generating the experimentally predicted oxacarbenium cation intermediate. We therefore stress that dissociative mechanisms should be studied with methodologies that account for the (bulk) environment in the optimization routine, where these effects are often only included as a correction to the energy in the current literature. In addition to accounting for charge stabilization through implicit solvation, nucleophile activation and leaving group stabilization should also be explicitly introduced into the model to further stabilize the system. Our work also emphasizes the importance of studying the Gibbs surface, which in some cases provides a better description of chemically important regions of the reaction surface or changes the calculated trend in the magnitude of dissociative barriers. In addition, it is proposed that the methodology presented in this study can be used to calculate uncatalyzed deglycosylation barriers for a range of DNA nucleosides, which when compared to the corresponding enzyme-catalyzed reactions, will allow the prediction of the rate enhancement (barrier reduction) due to the enzyme.
Collapse
Affiliation(s)
- Jennifer L Przybylski
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta T1K 3M4, Canada
| | | |
Collapse
|
26
|
Millen AL, Manderville RA, Wetmore SD. Conformational Flexibility of C8-Phenoxyl-2′-deoxyguanosine Nucleotide Adducts. J Phys Chem B 2010; 114:4373-82. [DOI: 10.1021/jp911993f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Andrea L. Millen
- Department of Chemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta, Canada, T1K 3M4, Department of Chemistry, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| | - Richard A. Manderville
- Department of Chemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta, Canada, T1K 3M4, Department of Chemistry, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| | - Stacey D. Wetmore
- Department of Chemistry, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta, Canada, T1K 3M4, Department of Chemistry, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| |
Collapse
|