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Sharma AD, Grewal RK, Gorle S, Cuspoca AF, Kaushik V, Rajjak Shaikh A, Cavallo L, Chawla M. T cell epitope based vaccine design while targeting outer capsid proteins of rotavirus strains infecting neonates: an immunoinformatics approach. J Biomol Struct Dyn 2024; 42:4937-4955. [PMID: 37382214 DOI: 10.1080/07391102.2023.2226721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/05/2023] [Indexed: 06/30/2023]
Abstract
Gastrointestinal diarrhea is majorly caused by the rotavirus (RV) in the children who generally are under the age group of 5 years. WHO estimates that ∼95% of the children contract RV infection, by this age. The disease is highly contagious; notably in many cases, it is proven fatal with high mortality rates especially in the developing countries. In India alone, an estimated 145,000 yearly deaths occurs due to RV related gastrointestinal diarrhea. WHO pre-qualified vaccines that are available for RV are all live attenuated vaccines with modest efficacy range between 40 and 60%. Further, the risk of intussusceptions has been reported in some children on RV vaccination. Thus, in a quest to develop alternative candidate to overcome challenges associated with these oral vaccines, we chose immunoinformatics approach to design a multi-epitope vaccine (MEV) while targeting the outer capsid viral proteinsVP4 and VP7 of the neonatal strains of rotavirus. Interestingly, ten epitopes, that is, six CD8+T-cells and four CD4+T-cell epitopes were identified which were predicted to be antigenic, non-allergic, non-toxic and stable. These epitopes were then linked to adjuvants, linkers, and PADRE sequences to create a multi-epitope vaccine for RV. The in silico designed RV-MEV and human TLR5 complex displayed stable interactions during molecular dynamics simulations. Further, the immune simulation studies of RV-MEV corroborated that the vaccine candidate emerges as a promising immunogen. Future investigations while performing in vitro and in vivo analyses with designed RV-MEV construct are highly desirable to warrant the potential of this vaccine candidate in protective immunity against different strains of RVs infecting neonates.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Arijit Das Sharma
- School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Ravneet Kaur Grewal
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, Haryana, India
| | - Suresh Gorle
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, Haryana, India
| | - Andrés Felipe Cuspoca
- Grupo de Investigación Epidemiología Clínica de Colombia (GRECO), Universidad Pedagógica y Tecnológica de Colombia, Tunja, Colombia
- Centro de Atención e Investigación Médica - CAIMED, Chía, Colombia
| | - Vikas Kaushik
- School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Abdul Rajjak Shaikh
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, Haryana, India
| | - Luigi Cavallo
- Physical Sciences and Engineering Division, Kaust Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Mohit Chawla
- Physical Sciences and Engineering Division, Kaust Catalysis Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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Chawla M, Poater A, Oliva R, Cavallo L. Unveiling structural and energetic characterization of the emissive RNA alphabet anchored in the methylthieno[3,4- d]pyrimidine heterocycle core. Phys Chem Chem Phys 2024; 26:16358-16368. [PMID: 38805177 DOI: 10.1039/d3cp06136a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
This study presents a comprehensive theoretical exploration of the fluorescent non-natural emissive nucleobases- mthA, mthG, mthC, and mthU derived from the methylthieno[3,4-d]pyrimidine heterocycle. Our calculations, aligning with experimental findings, reveal that these non-natural bases exert minimal influence on the geometry of classical Watson-Crick base pairs within an RNA duplex, maintaining H-bonding akin to natural bases. In terms of energy, the impact of the modified bases, but for mthG, is also found to be little significant. We delved into an in-depth analysis of the photophysical properties of these non-natural bases. This investigation unveiled a correlation between their absorption/emission peaks and the substantial impact of the modification on the energy levels of the highest unoccupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbital (LUMO). Notably, this alteration in energy levels resulted in a significant reduction of the HOMO-LUMO gap, from approximately 5.4-5.5 eV in the natural bases, to roughly 3.9-4.7 eV in the modified bases. This shift led to a consequential change in absorption and emission spectra towards longer wavelengths, elucidating their bathochromic shift.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, KAUST Catalysis Center, Thuwal 23955-6900, Saudi Arabia.
| | - Albert Poater
- Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona, c/Ma Aurèlia Capmany 69, Girona 17003, Catalonia, Spain
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, Naples, I-80143, Italy
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, KAUST Catalysis Center, Thuwal 23955-6900, Saudi Arabia.
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Kumar S, Reddy G. Mechanism of Fluoride Ion Encapsulation by Magnesium Ions in a Bacterial Riboswitch. J Phys Chem B 2023; 127:9267-9281. [PMID: 37851949 DOI: 10.1021/acs.jpcb.3c03941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Riboswitches sense various ions in bacteria and activate gene expression to synthesize proteins that help maintain ion homeostasis. The crystal structure of the aptamer domain (AD) of the fluoride riboswitch shows that the F- ion is encapsulated by three Mg2+ ions bound to the ligand-binding domain (LBD) located at the core of the AD. The assembly mechanism of this intricate structure is unknown. To this end, we performed computer simulations using coarse-grained and all-atom RNA models to bridge multiple time scales involved in riboswitch folding and ion binding. We show that F- encapsulation by the Mg2+ ions bound to the riboswitch involves multiple sequential steps. Broadly, two Mg2+ ions initially interact with the phosphate groups of the LBD using water-mediated outer-shell coordination and transition to a direct inner-shell interaction through dehydration to strengthen their interaction with the LBD. We propose that the efficient binding mode of the third Mg2+ and F- is that they form a water-mediated ion pair and bind to the LBD simultaneously to minimize the electrostatic repulsion between three Mg2+ bound to the LBD. The tertiary stacking interactions among the LBD nucleobases alone are insufficient to stabilize the alignment of the phosphate groups to facilitate Mg2+ binding. We show that the stability of the whole assembly is an intricate balance of the interactions among the five phosphate groups, three Mg2+, and the encapsulated F- ion aided by the Mg2+ solvated water. These insights are helpful in the rational design of RNA-based ion sensors and fast-switching logic gates.
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Affiliation(s)
- Sunil Kumar
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru, Karnataka 560012, India
| | - Govardhan Reddy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru, Karnataka 560012, India
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Nguyen TL, Samuel Leon Magdaleno J, Rajjak Shaikh A, Choowongkomon K, Li V, Lee Y, Kim H. Designing a multi-epitope candidate vaccine by employing immunoinformatics approaches to control African swine fever spread. J Biomol Struct Dyn 2023; 41:10214-10229. [PMID: 36510707 DOI: 10.1080/07391102.2022.2153922] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 11/25/2022] [Indexed: 12/15/2022]
Abstract
The African swine fever virus has been circulating for decades and is highly infectious, often fatal to farmed and wild pigs. There is currently no approved vaccine or treatment for the disease, making prevention even more difficult. Therefore, vaccine development is necessary and urgent to limit the consequences of ASF and ensure the food chain and sustainability of the swine industry. This research study was conducted to design a multi-epitope vaccine for controlling veterinary diseases caused by the African swine fever virus. We employed the immunoinformatics approaches to reveal 37 epitopes from different viral proteins of ASFV. These epitopes were linked to adjuvants and linkers to form a full-fledged immunogenic vaccine construct. The tertiary structure of the final vaccine was predicted using a deep-learning approach. The molecular docking and molecular dynamics predicted stable interactions between the vaccine and immune receptor TLR5 of Sus scrofa (Pig). The MD simulation studies reflect that the calculated parameters like RMSD, RMSF, number of hydrogen bonds, and finally, the buried interface surface area for the complex remained stable throughout the simulation time. This analysis suggests the stability of interface interactions between the TLR5 and the multi-epitope vaccine construct. Further, the physiochemical analysis demonstrated that our designed vaccine construct was expected to have high stability and prolonged half-life time in mammalian cells. Traditional vaccine design experiments require significant time and financial input from the development stage to the final product. Studies like this can assist in accelerating vaccine development while minimizing the cost.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Truc Ly Nguyen
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
| | - Jorge Samuel Leon Magdaleno
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, Haryana, India
| | - Abdul Rajjak Shaikh
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, Haryana, India
- Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok, Thailand
| | | | - Vladimir Li
- Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul, Republic of Korea
| | - Youngho Lee
- Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul, Republic of Korea
| | - Heebal Kim
- Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Interdisciplinary Program in Bioinformatics, Seoul National University, Seoul, Republic of Korea
- eGnome, Inc., Seoul, Republic of Korea
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Hu G, Zhang Y, Yu Z, Cui T, Cui W. Dynamical characterization and multiple unbinding paths of two PreQ 1 ligands in one pocket. Phys Chem Chem Phys 2023; 25:24004-24015. [PMID: 37646322 DOI: 10.1039/d3cp03142j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Riboswitches naturally regulate gene expression in bacteria by binding to specific small molecules. Class 1 preQ1 riboswitch aptamer is an important model not only for RNA folding but also as a target for designing small molecule antibiotics due to its well-known minimal aptamer domain. Here, we ran a total of 62.4 μs conventional and enhanced-sampling molecular dynamics (MD) simulations to characterize the determinants underlying the binding of the preQ1-II riboswitch aptamer to two preQ1 ligands in one binding pocket. Decomposition of binding free energy suggested that preQ1 ligands at α and β sites interact with four nucleotides (G5, C17, C18, and A30) and two nucleotides (A12 and C31), respectively. Mg2+ ions play a crucial role in both stabilizing the binding pocket and facilitating ligand binding. The flexible preQ1 ligand at the β site leads to the top of the binding pocket loosening and thus pre-organizes the riboswitch for ligand entry. Enhanced sampling simulations further revealed that the preQ1 ligand at the α site unbinds through two orthogonal pathways, which are dependent on whether or not a β site preQ1 ligand is present. One of the two preQ1 ligands has been identified in the binding pocket, which will aid to identify the second preQ1 Ligand. Our work provides new information for designing robust ligands.
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Affiliation(s)
- Guodong Hu
- Shandong Key Laboratory of Biophysics, Dezhou University, Dezhou 253023, China.
- Laoling People's Hospital, Dezhou 253600, China
| | | | - Zhiping Yu
- Shandong Key Laboratory of Biophysics, Dezhou University, Dezhou 253023, China.
| | - Tiejun Cui
- Laoling People's Hospital, Dezhou 253600, China
| | - Wanling Cui
- Shandong Key Laboratory of Biophysics, Dezhou University, Dezhou 253023, China.
- Laoling People's Hospital, Dezhou 253600, China
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Chawla M, Kalra K, Cao Z, Cavallo L, Oliva R. Occurrence and stability of anion-π interactions between phosphate and nucleobases in functional RNA molecules. Nucleic Acids Res 2022; 50:11455-11469. [PMID: 36416268 PMCID: PMC9723503 DOI: 10.1093/nar/gkac1081] [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: 05/13/2022] [Revised: 10/19/2022] [Accepted: 10/26/2022] [Indexed: 11/24/2022] Open
Abstract
We present a systematic structural and energetic characterization of phosphate(OP)-nucleobase anion…π stacking interactions in RNAs. We observed OP-nucleobase stacking contacts in a variety of structural motifs other than regular helices and spanning broadly diverse sequence distances. Apart from the stacking between a phosphate and a guanine or a uracil two-residue upstream in specific U-turns, such interactions in RNA have been scarcely characterized to date. Our QM calculations showed an energy minimum at a distance between the OP atom and the nucleobase plane centroid slightly below 3 Å for all the nucleobases. By sliding the OP atom over the nucleobase plane we localized the optimal mutual positioning of the stacked moieties, corresponding to an energy minimum below -6 kcal•mol-1, for all the nucleobases, consistently with the projections of the OP atoms over the different π-rings we observed in experimental occurrences. We also found that the strength of the interaction clearly correlates with its electrostatic component, pointing to it as the most relevant contribution. Finally, as OP-uracil and OP-guanine interactions represent together 86% of the instances we detected, we also proved their stability under dynamic conditions in model systems simulated by state-of-the art DFT-MD calculations.
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Affiliation(s)
- Mohit Chawla
- Correspondence may also be addressed to Mohit Chawla. ;
| | - Kanav Kalra
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad 121002, Haryana, India
| | - Zhen Cao
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Luigi Cavallo
- Correspondence may also be addressed to Luigi Cavallo. Tel: +966 02 8027566; Fax: +966 02 8021347;
| | - Romina Oliva
- To whom correspondence should be addressed. Tel: +39 081 5476541; Fax: +39 081 5476514;
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Immunoinformatics-Aided Design of a Peptide Based Multiepitope Vaccine Targeting Glycoproteins and Membrane Proteins against Monkeypox Virus. Viruses 2022; 14:v14112374. [PMID: 36366472 PMCID: PMC9693848 DOI: 10.3390/v14112374] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 10/22/2022] [Accepted: 10/25/2022] [Indexed: 01/31/2023] Open
Abstract
Monkeypox is a self-limiting zoonotic viral disease and causes smallpox-like symptoms. The disease has a case fatality ratio of 3-6% and, recently, a multi-country outbreak of the disease has occurred. The currently available vaccines that have provided immunization against monkeypox are classified as live attenuated vaccinia virus-based vaccines, which pose challenges of safety and efficacy in chronic infections. In this study, we have used an immunoinformatics-aided design of a multi-epitope vaccine (MEV) candidate by targeting monkeypox virus (MPXV) glycoproteins and membrane proteins. From these proteins, seven epitopes (two T-helper cell epitopes, four T-cytotoxic cell epitopes and one linear B cell epitopes) were finally selected and predicted as antigenic, non-allergic, interferon-γ activating and non-toxic. These epitopes were linked to adjuvants to design a non-allergic and antigenic candidate MPXV-MEV. Further, molecular docking and molecular dynamics simulations predicted stable interactions between predicted MEV and human receptor TLR5. Finally, the immune-simulation analysis showed that the candidate MPXV-MEV could elicit a human immune response. The results obtained from these in silico experiments are promising but require further validation through additional in vivo experiments.
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Kaushik V, Jain P, Akhtar N, Joshi A, Gupta LR, Grewal RK, Oliva R, Shaikh AR, Cavallo L, Chawla M. Immunoinformatics-Aided Design and In Vivo Validation of a Peptide-Based Multiepitope Vaccine Targeting Canine Circovirus. ACS Pharmacol Transl Sci 2022. [DOI: 10.1021/acsptsci.2c00130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Vikas Kaushik
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Phagwara 144001, Punjab, India
| | - Pankaj Jain
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Phagwara 144001, Punjab, India
| | - Nahid Akhtar
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Phagwara 144001, Punjab, India
| | - Amit Joshi
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Phagwara 144001, Punjab, India
| | - Lovi Raj Gupta
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Phagwara 144001, Punjab, India
| | - Ravneet Kaur Grewal
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad 121002, Haryana, India
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143, Naples, Italy
| | - Abdul Rajjak Shaikh
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad 121002, Haryana, India
| | - Luigi Cavallo
- Physical Sciences and Engineering Division, Kaust Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Mohit Chawla
- Physical Sciences and Engineering Division, Kaust Catalysis Center, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
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Kaushik V, G SK, Gupta LR, Kalra U, Shaikh AR, Cavallo L, Chawla M. Immunoinformatics Aided Design and In-Vivo Validation of a Cross-Reactive Peptide Based Multi-Epitope Vaccine Targeting Multiple Serotypes of Dengue Virus. Front Immunol 2022; 13:865180. [PMID: 35799781 PMCID: PMC9254734 DOI: 10.3389/fimmu.2022.865180] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 05/05/2022] [Indexed: 02/03/2023] Open
Abstract
Dengue virus (DENV) is an arboviral disease affecting more than 400 million people annually. Only a single vaccine formulation is available commercially and many others are still under clinical trials. Despite all the efforts in vaccine designing, the improvement in vaccine formulation against DENV is very much needed. In this study, we used a roboust immunoinformatics approach, targeting all the four serotypes of DENV to design a multi-epitope vaccine. A total of 13501 MHC II binding CD4+ epitope peptides were predicted from polyprotein sequences of four dengue virus serotypes. Among them, ten conserved epitope peptides that were interferon-inducing were selected and found to be conserved among all the four dengue serotypes. The vaccine was formulated using antigenic, non-toxic and conserved multi epitopes discovered in the in-silico study. Further, the molecular docking and molecular dynamics predicted stable interactions between predicted vaccine and immune receptor, TLR-5. Finally, one of the mapped epitope peptides was synthesized for the validation of antigenicity and antibody production ability where the in-vivo tests on rabbit model was conducted. Our in-vivo analysis clearly indicate that the imunogen designed in this study could stimulate the production of antibodies which further suggest that the vaccine designed possesses good immunogenicity.
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Affiliation(s)
- Vikas Kaushik
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Sunil Krishnan G
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Lovi Raj Gupta
- Domain of Bioinformatics, School of Bio-Engineering and Bio-Sciences, Lovely Professional University, Punjab, India
| | - Utkarsh Kalra
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, India
- Department of Data Science, Innopolis University, Innopolis, Russia
| | - Abdul Rajjak Shaikh
- Department of Research and Innovation, STEMskills Research and Education Lab Private Limited, Faridabad, India
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
| | - Luigi Cavallo
- Kaust Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
| | - Mohit Chawla
- Kaust Catalysis Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- *Correspondence: Abdul Rajjak Shaikh, ; Luigi Cavallo, ; Mohit Chawla, ;
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Ma Y, Mou Q, Yan P, Yang Z, Xiong Y, Yan D, Zhang C, Zhu X, Lu Y. A highly sensitive and selective fluoride sensor based on a riboswitch-regulated transcription coupled with CRISPR-Cas13a tandem reaction. Chem Sci 2021; 12:11740-11747. [PMID: 34659710 PMCID: PMC8442723 DOI: 10.1039/d1sc03508h] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 07/20/2021] [Indexed: 12/26/2022] Open
Abstract
Nucleic acid sensors have realized much success in detecting positively charged and neutral molecules, but have rarely been applied for measuring negatively charged molecules, such as fluoride, even though an effective sensor is needed to promote dental health while preventing osteofluorosis and other diseases. To address this issue, we herein report a quantitative fluoride sensor with a portable fluorometer readout based on fluoride riboswitch-regulated transcription coupled with CRISPR-Cas13-based signal amplification. This tandem sensor utilizes the fluoride riboswitch to regulate in vitro transcription and generate full-length transcribed RNA that can be recognized by CRISPR-Cas13a, triggering the collateral cleavage of the fluorophore-quencher labeled RNA probe and generating a fluorescence signal output. This tandem sensor can quantitatively detect fluoride at ambient temperature in aqueous solution with high sensitivity (limit of detection (LOD) ≈ 1.7 μM), high selectivity against other common anions, a wide dynamic range (0-800 μM) and a short sample-to-answer time (30 min). This work expands the application of nucleic acid sensors to negatively charged targets and demonstrates their potential for the on-site and real-time detection of fluoride in environmental monitoring and point-of-care diagnostics.
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Affiliation(s)
- Yuan Ma
- Department of Chemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China
| | - Quanbing Mou
- Department of Chemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Peng Yan
- Department of Chemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University 710049 Xi'an PR China
| | - Zhenglin Yang
- Department of Biochemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Ying Xiong
- Department of Chemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
| | - Deyue Yan
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China
| | - Chuan Zhang
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China
| | - Xinyuan Zhu
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA
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Shaikh AR, Chawla M, Hassan AA, Abdulazeez I, Salawu OA, Siddiqui MN, Pervez S, Cavallo L. Adsorption of industrial dyes on functionalized and nonfunctionalized asphaltene: A combined molecular dynamics and quantum mechanics study. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116433] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Chen J, Li N, Wang X, Chen J, Zhang JZH, Zhu T. Molecular mechanism related to the binding of fluorophores to Mango-II revealed by multiple-replica molecular dynamics simulations. Phys Chem Chem Phys 2021; 23:10636-10649. [PMID: 33904542 DOI: 10.1039/d0cp06438f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Recently, RNA aptamers activating small-molecule fluorophores have been successfully applied to tag and track RNAs in vivo. It is of significance to investigate the molecular mechanism of the fluorophore-RNA aptamer bindings at the atomic level to seek a possible pathway to enhance the fluorescence efficiency of fluorophores. In this work, multiple replica molecular dynamics (MRMD) simulations, essential dynamics (ED) analysis, and hierarchical clustering analysis were coupled to probe the effect of A22U mutation on the binding of two fluorophores, TO1-Biotin (TO1) and TO3-Biotin (TO3), to the Mango-II RNA aptamer (Mango-II). ED analysis reveals that A22U induces alterations in the binding pocket and sites of TO1 and TO3 to the Mango-II, which in turn tunes the fluorophore-RNA interface and changes the interactions of TO1 and TO3 with separate nucleotides of Mango-II. Dynamics analyses also uncover that A22U exerts the opposite impact on the molecular surface areas of the Mango-II and sugar puckers of nucleotides 22 and 23 in Mango-II complexed with TO1 and TO3. Moreover, the calculations of binding free energies suggest that A22U strengthens the binding ability of TO1 to the mutated Mango-II but weakens TO3 to the mutated Mango-II when compared with WT. These findings imply that point mutation in nucleotides possibly tune the fluorescence of fluorophores binding to RNA aptamers, providing a possible scheme to enhance the fluorescence of fluorophores.
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Affiliation(s)
- Junxiao Chen
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, People's Republic of China. and School of Chemistry and Pharmaceutical Engineering, Qilu University of Technology, Jinan, 250353, People's Republic of China
| | - Na Li
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, People's Republic of China.
| | - Xingyu Wang
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai, People's Republic of China
| | - Jianzhong Chen
- School of Science, Shandong Jiaotong University, Jinan 250357, People's Republic of China.
| | - John Z H Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, People's Republic of China. and NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai, People's Republic of China
| | - Tong Zhu
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, People's Republic of China. and NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai, People's Republic of China and Shandong Key Laboratory of Biophysics, Institute of Biophysics, Dezhou University, Dezhou 253023, China
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13
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Chawla M, Gorle S, Shaikh AR, Oliva R, Cavallo L. Replacing thymine with a strongly pairing fifth Base: A combined quantum mechanics and molecular dynamics study. Comput Struct Biotechnol J 2021; 19:1312-1324. [PMID: 33738080 PMCID: PMC7940798 DOI: 10.1016/j.csbj.2021.02.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 02/06/2021] [Accepted: 02/09/2021] [Indexed: 01/14/2023] Open
Abstract
The non-natural ethynylmethylpyridone C-nucleoside (W), a thymidine (T) analogue that can be incorporated in oligonucleotides by automated synthesis, has recently been reported to form a high fidelity base pair with adenosine (A) and to be well accommodated in B-DNA duplexes. The enhanced binding affinity for A of W, as compared to T, makes it an ideal modification for biotechnological applications, such as efficient probe hybridization for the parallel detection of multiple DNA strands. In order to complement the experimental study and rationalize the impact of the non-natural W nucleoside on the structure, stability and dynamics of DNA structures, we performed quantum mechanics (QM) calculations along with molecular dynamics (MD) simulations. Consistently with the experimental study, our QM calculations show that the A:W base pair has an increased stability as compared to the natural A:T pair, due to an additional CH-π interaction. Furthermore, we show that mispairing between W and guanine (G) causes a distortion in the planarity of the base pair, thus explaining the destabilization of DNA duplexes featuring a G:W pair. MD simulations show that incorporation of single or multiple consecutive A:W pairs in DNA duplexes causes minor changes to the intra- and inter-base geometrical parameters, while a moderate widening/shrinking of the major/minor groove of the duplexes is observed. QM calculations applied to selected stacks from the MD simulations also show an increased stacking energy for W, over T, with the neighboring bases.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Suresh Gorle
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Abdul Rajjak Shaikh
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143 Naples, Italy
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
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14
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Calero P, Volke DC, Lowe PT, Gotfredsen CH, O'Hagan D, Nikel PI. A fluoride-responsive genetic circuit enables in vivo biofluorination in engineered Pseudomonas putida. Nat Commun 2020; 11:5045. [PMID: 33028813 PMCID: PMC7541441 DOI: 10.1038/s41467-020-18813-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/16/2020] [Indexed: 12/20/2022] Open
Abstract
Fluorine is a key element in the synthesis of molecules broadly used in medicine, agriculture and materials. Addition of fluorine to organic structures represents a unique strategy for tuning molecular properties, yet this atom is rarely found in Nature and approaches to integrate fluorometabolites into the biochemistry of living cells are scarce. In this work, synthetic gene circuits for organofluorine biosynthesis are implemented in the platform bacterium Pseudomonas putida. By harnessing fluoride-responsive riboswitches and the orthogonal T7 RNA polymerase, biochemical reactions needed for in vivo biofluorination are wired to the presence of fluoride (i.e. circumventing the need of feeding expensive additives). Biosynthesis of fluoronucleotides and fluorosugars in engineered P. putida is demonstrated with mineral fluoride both as only fluorine source (i.e. substrate of the pathway) and as inducer of the synthetic circuit. This approach expands the chemical landscape of cell factories by providing alternative biosynthetic strategies towards fluorinated building-blocks. Addition of fluorine to organic structures is a unique strategy for tuning molecular properties, but approaches to integrate fluorometabolites into the biochemistry of living cells are scarce. Here, the authors develop a fluoride-responsive genetic circuit to enable in vivo biofluorination in engineered Pseudomonas putida.
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Affiliation(s)
- Patricia Calero
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Daniel C Volke
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Phillip T Lowe
- School of Chemistry, University of St. Andrews, KY16 9ST St, Andrews, UK
| | | | - David O'Hagan
- School of Chemistry, University of St. Andrews, KY16 9ST St, Andrews, UK
| | - Pablo I Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark.
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15
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Kalra K, Gorle S, Cavallo L, Oliva R, Chawla M. Occurrence and stability of lone pair-π and OH-π interactions between water and nucleobases in functional RNAs. Nucleic Acids Res 2020; 48:5825-5838. [PMID: 32392301 PMCID: PMC7293021 DOI: 10.1093/nar/gkaa345] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 04/21/2020] [Accepted: 05/07/2020] [Indexed: 01/15/2023] Open
Abstract
We identified over 1000 instances of water-nucleobase stacking contacts in a variety of RNA molecules from a non-redundant set of crystal structures with resolution ≤3.0 Å. Such contacts may be of either the lone pair-π (lp-π) or the OH-π type, in nature. The distribution of the distances of the water oxygen from the nucleobase plane peaks at 3.5 Å for A, G and C, and approximately at 3.1-3.2 Å for U. Quantum mechanics (QM) calculations confirm, as expected, that the optimal energy is reached at a shorter distance for the lp-π interaction as compared to the OH-π one (3.0 versus 3.5 Å). The preference of each nucleobase for either type of interaction closely correlates with its electrostatic potential map. Furthermore, QM calculations show that for all the nucleobases a favorable interaction, of either the lp-π or the OH-π type, can be established at virtually any position of the water molecule above the nucleobase skeleton, which is consistent with the uniform projection of the OW atoms over the nucleobases ring we observed in the experimental occurrences. Finally, molecular dynamics simulations of a model system for the characterization of water-nucleobase stacking contacts confirm the stability of these interactions also under dynamic conditions.
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Affiliation(s)
- Kanav Kalra
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Suresh Gorle
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143 Naples, Italy
| | - Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
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16
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Abstract
Biocatalysis is dominated by protein enzymes, and only a few classes of ribozymes are known to contribute to the task of promoting biochemical transformations. The RNA World theory encompasses the notion that earlier forms of life made use of a much greater diversity of ribozymes and other functional RNAs to guide complex metabolic states long before proteins had emerged in evolution. In recent years, the discoveries of various classes of ribozymes, riboswitches, and other noncoding RNAs in bacteria have provided additional support for the hypothesis that RNA molecules indeed have the catalytic competence to promote diverse chemical reactions without the aid of protein enzymes. Herein, some of the most striking observations made from examinations of natural riboswitches that bind small ligands are highlighted and used as a basis to imagine the characteristics and functions of long-extinct ribozymes from the RNA World.
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Affiliation(s)
- Ronald R. Breaker
- Department of Molecular, Cellular and Developmental Biology, Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Department of Chemistry, Yale University, 260 Whitney Avenue, New Haven, Connecticut 06520, United States
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17
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Zhou T, Wang H, Song L, Zhao Y. Computational study of switching mechanism in add A-riboswitch. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2020. [DOI: 10.1142/s0219633620400015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Riboswitch can bind small molecules to regulate gene expression. Unlike other RNAs, riboswitch relies on its conformational switching for regulation. However, the understanding of the switching mechanism is still limited. Here, we focussed on the add A-riboswitch to illustrate the dynamical switching mechanism as an example. We performed molecular dynamics simulation, conservation and co-evolution calculations to infer the dynamical motions and evolutionary base pairings. The results suggest that the binding domain is stable for molecule recognition and binding, whereas the switching base pairings are co-evolutionary for translation. The understanding of the add A-riboswitch switching mechanism provides a potential solution for riboswitch drug design.
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Affiliation(s)
- Ting Zhou
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, P. R. China
| | - Huiwen Wang
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, P. R. China
| | - Linlu Song
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, P. R. China
| | - Yunjie Zhao
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan 430079, P. R. China
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18
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Cassone G, Kruse H, Sponer J. Interactions between cyclic nucleotides and common cations: an ab initio molecular dynamics study. Phys Chem Chem Phys 2019; 21:8121-8132. [PMID: 30932112 DOI: 10.1039/c8cp07492e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We present the first, to the best of our knowledge, ab initio molecular dynamics (AIMD) investigation on three aqueous solutions where an abasic cyclic nucleotide model is solvated in the presence of distinct cations (i.e., Na+, K+ and Mg2+). We elucidate the typical modalities of interaction between those ionic species and the nucleotide moiety by first-principles numerical simulations, starting from an inner-shell binding configuration on a time scale of 100 ps (total simulation time of ∼600 ps). Whereas the strong "structure-maker" Mg2+ is permanently bound to one of the two oxygen atoms of the phosphate group of the nucleotide model, Na+ and K+ show binding times τb of 65 ps and 10-15 ps, respectively, thus reflecting their chemical nature in aqueous solutions. Furthermore, we qualitatively relate these findings to approximate free-energy barriers of the cations' unbinding obtained by means of exploratory well-tempered metadynamics. With the aim of shedding light on the features of commonly employed force-fields (FFs), classical MD simulations (almost 200 trajectories with a total simulation time of ∼18 μs) using the biomolecular AMBER FF are also reported. By choosing several combinations of the parametrization for the water environment (i.e., TIP3P, SPC/E and OPC) and cations (i.e., Joung-Cheatham, Li-Merz 12-6 and Li-Merz 12-6-4), we found significant differences in the radial distribution functions and residence times compared to the ab initio results. The Na+ and K+ ions wrongly show quasi-identical radial distribution functions and the Li & Merz 12-6-4 Lennard-Jones parameters for Mg2+ were found to be essential in quickly reaching the binding state consistent with AIMD.
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Affiliation(s)
- Giuseppe Cassone
- Institute of Biophysics of the Czech Academy of Sciences, v.v.i, Královopolská 135, 61265 Brno, Czech Republic.
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19
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Krepl M, Vögele J, Kruse H, Duchardt-Ferner E, Wöhnert J, Sponer J. An intricate balance of hydrogen bonding, ion atmosphere and dynamics facilitates a seamless uracil to cytosine substitution in the U-turn of the neomycin-sensing riboswitch. Nucleic Acids Res 2018; 46:6528-6543. [PMID: 29893898 PMCID: PMC6061696 DOI: 10.1093/nar/gky490] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/23/2018] [Indexed: 01/04/2023] Open
Abstract
The neomycin sensing riboswitch is the smallest biologically functional RNA riboswitch, forming a hairpin capped with a U-turn loop-a well-known RNA motif containing a conserved uracil. It was shown previously that a U→C substitution of the eponymous conserved uracil does not alter the riboswitch structure due to C protonation at N3. Furthermore, cytosine is evolutionary permitted to replace uracil in other U-turns. Here, we use molecular dynamics simulations to study the molecular basis of this substitution in the neomycin sensing riboswitch and show that a structure-stabilizing monovalent cation-binding site in the wild-type RNA is the main reason for its negligible structural effect. We then use NMR spectroscopy to confirm the existence of this cation-binding site and to demonstrate its effects on RNA stability. Lastly, using quantum chemical calculations, we show that the cation-binding site is altering the electronic environment of the wild-type U-turn so that it is more similar to the cytosine mutant. The study reveals an amazingly complex and delicate interplay between various energy contributions shaping up the 3D structure and evolution of nucleic acids.
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Affiliation(s)
- Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Jennifer Vögele
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Holger Kruse
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
| | - Elke Duchardt-Ferner
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jens Wöhnert
- Institute of Molecular Biosciences and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Jiri Sponer
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65 Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic
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20
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Chawla M, Poater A, Besalú-Sala P, Kalra K, Oliva R, Cavallo L. Theoretical characterization of sulfur-to-selenium substitution in an emissive RNA alphabet: impact on H-bonding potential and photophysical properties. Phys Chem Chem Phys 2018; 20:7676-7685. [PMID: 29497733 DOI: 10.1039/c7cp07656h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We employ density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to investigate the structural, energetic and optical properties of a new computationally designed RNA alphabet, where the nucleobases, tsA, tsG, tsC, and tsU (ts-bases), have been derived by replacing sulfur with selenium in the previously reported tz-bases, based on the isothiazolo[4,3-d]pyrimidine heterocycle core. We find out that the modeled non-natural bases have minimal impact on the geometry and energetics of the classical Watson-Crick base pairs, thus potentially mimicking the natural bases in a RNA duplex in terms of H-bonding. In contrast, our calculations indicate that H-bonded base pairs involving the Hoogsteen edge of purines are destabilized as compared to their natural counterparts. We also focus on the photophysical properties of the non-natural bases and correlate their absorption/emission peaks to the strong impact of the modification on the energy of the lowest unoccupied molecular orbital. It is indeed stabilized by roughly 1.1-1.6 eV as compared to the natural analogues, resulting in a reduction of the gap between the highest occupied and the lowest unoccupied molecular orbital from 5.3-5.5 eV in the natural bases to 3.9-4.2 eV in the modified ones, with a consequent bathochromic shift in the absorption and emission spectra. Overall, our analysis clearly indicates that the newly modelled ts-bases are expected to exhibit better fluorescent properties as compared to the previously reported tz-bases, while retaining similar H-bonding properties. In addition, we show that a new RNA alphabet based on size-extended benzo-homologated ts-bases can also form stable Watson-Crick base pairs with the natural complementary nucleobases.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, KAUST Catalysis Center, Thuwal 23955-6900, Saudi Arabia.
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21
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Antunes D, Jorge NAN, Caffarena ER, Passetti F. Using RNA Sequence and Structure for the Prediction of Riboswitch Aptamer: A Comprehensive Review of Available Software and Tools. Front Genet 2018; 8:231. [PMID: 29403526 PMCID: PMC5780412 DOI: 10.3389/fgene.2017.00231] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/21/2017] [Indexed: 12/14/2022] Open
Abstract
RNA molecules are essential players in many fundamental biological processes. Prokaryotes and eukaryotes have distinct RNA classes with specific structural features and functional roles. Computational prediction of protein structures is a research field in which high confidence three-dimensional protein models can be proposed based on the sequence alignment between target and templates. However, to date, only a few approaches have been developed for the computational prediction of RNA structures. Similar to proteins, RNA structures may be altered due to the interaction with various ligands, including proteins, other RNAs, and metabolites. A riboswitch is a molecular mechanism, found in the three kingdoms of life, in which the RNA structure is modified by the binding of a metabolite. It can regulate multiple gene expression mechanisms, such as transcription, translation initiation, and mRNA splicing and processing. Due to their nature, these entities also act on the regulation of gene expression and detection of small metabolites and have the potential to helping in the discovery of new classes of antimicrobial agents. In this review, we describe software and web servers currently available for riboswitch aptamer identification and secondary and tertiary structure prediction, including applications.
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Affiliation(s)
- Deborah Antunes
- Scientific Computing Program (PROCC), Computational Biophysics and Molecular Modeling Group, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Natasha A N Jorge
- Laboratory of Functional Genomics and Bioinformatics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Laboratory of Gene Expression Regulation, Carlos Chagas Institute, Fundação Oswaldo Cruz, Curitiba, Brazil
| | - Ernesto R Caffarena
- Scientific Computing Program (PROCC), Computational Biophysics and Molecular Modeling Group, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Fabio Passetti
- Laboratory of Functional Genomics and Bioinformatics, Oswaldo Cruz Institute, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Laboratory of Gene Expression Regulation, Carlos Chagas Institute, Fundação Oswaldo Cruz, Curitiba, Brazil
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22
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Chawla M, Autiero I, Oliva R, Cavallo L. Energetics and dynamics of the non-natural fluorescent 4AP:DAP base pair. Phys Chem Chem Phys 2018; 20:3699-3709. [DOI: 10.1039/c7cp07400j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Quantum mechanics and molecular dynamics methods are used to compare the non-natural 4AP–DAP base pair to natural base pairs.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST)
- Physical Sciences and Engineering Division
- Thuwal 23955-6900
- Saudi Arabia
| | - Ida Autiero
- King Abdullah University of Science and Technology (KAUST)
- Physical Sciences and Engineering Division
- Thuwal 23955-6900
- Saudi Arabia
| | - Romina Oliva
- Department of Sciences and Technologies
- University Parthenope of Naples
- Centro Direzionale Isola C4
- Naples
- Italy
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST)
- Physical Sciences and Engineering Division
- Thuwal 23955-6900
- Saudi Arabia
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23
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Chawla M, Poater A, Oliva R, Cavallo L. Structural and energetic characterization of the emissive RNA alphabet based on the isothiazolo[4,3-d]pyrimidine heterocycle core. Phys Chem Chem Phys 2016; 18:18045-53. [PMID: 27328414 DOI: 10.1039/c6cp03268k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We present theoretical characterization of fluorescent non-natural nucleobases, (tz)A, (tz)G, (tz)C, and (tz)U, derived from the isothiazolo[4,3-d]pyrimidine heterocycle. Consistent with the experimental evidence, our calculations show that the non-natural bases have minimal impact on the geometry and stability of the classical Watson-Crick base pairs, allowing them to accurately mimic natural bases in a RNA duplex, in terms of H-bonding. In contrast, our calculations indicate that H-bonded base pairs involving the Hoogsteen edge are destabilized relative to their natural counterparts. Analysis of the photophysical properties of the non-natural bases allowed us to correlate their absorption/emission peaks to the strong impact of the modification on the energy of the lowest unoccupied molecular orbital, LUMO, which is stabilized by roughly 1.0-1.2 eV relative to the natural analogues, while the highest occupied molecular orbital, HOMO, is not substantially affected. As a result, the HOMO-LUMO gap is reduced from 5.3-5.5 eV in the natural bases to 4.0-4.4 eV in the modified ones, with a consequent bathochromic shift in the absorption and emission spectra.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, KAUST Catalysis Center, Thuwal 23955-6900, Saudi Arabia.
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24
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Chawla M, Credendino R, Chermak E, Oliva R, Cavallo L. Theoretical Characterization of the H-Bonding and Stacking Potential of Two Nonstandard Nucleobases Expanding the Genetic Alphabet. J Phys Chem B 2016; 120:2216-24. [DOI: 10.1021/acs.jpcb.6b00125] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Mohit Chawla
- Physical
Sciences and Engineering Division (PSE), Kaust Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Raffaele Credendino
- Physical
Sciences and Engineering Division (PSE), Kaust Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Edrisse Chermak
- Physical
Sciences and Engineering Division (PSE), Kaust Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Romina Oliva
- Department
of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143 Naples, Italy
| | - Luigi Cavallo
- Physical
Sciences and Engineering Division (PSE), Kaust Catalysis Center (KCC), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
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25
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Kopniczky MB, Moore SJ, Freemont PS. Multilevel Regulation and Translational Switches in Synthetic Biology. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2015; 9:485-496. [PMID: 26336145 DOI: 10.1109/tbcas.2015.2451707] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In contrast to the versatility of regulatory mechanisms in natural systems, synthetic genetic circuits have been so far predominantly composed of transcriptionally regulated modules. This is about to change as the repertoire of foundational tools for post-transcriptional regulation is quickly expanding. We provide an overview of the different types of translational regulators: protein, small molecule and ribonucleic acid (RNA) responsive and we describe the new emerging circuit designs utilizing these tools. There are several advantages of achieving multilevel regulation via translational switches and it is likely that such designs will have the greatest and earliest impact in mammalian synthetic biology for regenerative medicine and gene therapy applications.
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26
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Chawla M, Oliva R, Bujnicki JM, Cavallo L. An atlas of RNA base pairs involving modified nucleobases with optimal geometries and accurate energies. Nucleic Acids Res 2015; 43:6714-29. [PMID: 26117545 PMCID: PMC4538814 DOI: 10.1093/nar/gkv606] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/28/2015] [Indexed: 01/08/2023] Open
Abstract
Posttranscriptional modifications greatly enhance the chemical information of RNA molecules, contributing to explain the diversity of their structures and functions. A significant fraction of RNA experimental structures available to date present modified nucleobases, with half of them being involved in H-bonding interactions with other bases, i.e. ‘modified base pairs’. Herein we present a systematic investigation of modified base pairs, in the context of experimental RNA structures. To this end, we first compiled an atlas of experimentally observed modified base pairs, for which we recorded occurrences and structural context. Then, for each base pair, we selected a representative for subsequent quantum mechanics calculations, to find out its optimal geometry and interaction energy. Our structural analyses show that most of the modified base pairs are non Watson–Crick like and are involved in RNA tertiary structure motifs. In addition, quantum mechanics calculations quantify and provide a rationale for the impact of the different modifications on the geometry and stability of the base pairs they participate in.
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Affiliation(s)
- Mohit Chawla
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
| | - Romina Oliva
- Department of Sciences and Technologies, University Parthenope of Naples, Centro Direzionale Isola C4, I-80143, Naples, Italy
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. Ks. Trojdena 4, 02-109 Warsaw, Poland Laboratory of Bioinformatics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland
| | - Luigi Cavallo
- King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division, Kaust Catalysis Center, Thuwal 23955-6900, Saudi Arabia
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