1
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Deng Z, Liu C, Li Z, Zhang Y. An efficient method by combining different basis sets and SAPT levels. J Comput Chem 2024; 45:1936-1944. [PMID: 38703182 DOI: 10.1002/jcc.27386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 05/06/2024]
Abstract
In symmetry-adapted perturbation theory (SAPT), accurate calculations on non-covalent interaction (NCI) for large complexes with more than 50 atoms are time-consuming using large basis sets. More efficient ones with smaller basis sets usually result in poor prediction in terms of dispersion and overall energies. In this study, we propose two composite methods with baseline calculated at SAPT2/aug-cc-pVDZ and SAPT2/aug-cc-pVTZ with dispersion term corrected at SAPT2+ level using bond functions and smaller basis set with δ MP2 corrections respectively. Benchmark results on representative NCI data sets, such as S22, S66, and so forth, show significant improvements on the accuracy compared to the original SAPT Silver standard and comparable to SAPT Gold standard in some cases with much less computational cost.
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Affiliation(s)
- Zhihao Deng
- Beijing StoneWise Technology Co Ltd., Beijing, China
| | - Chang Liu
- Beijing StoneWise Technology Co Ltd., Beijing, China
| | - Zhongwei Li
- Yantai Gogetter Technology Co Ltd., Yantai, China
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2
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Scheiner S, Derewenda ZS. Differing Effects of Nonlinearity around the Proton Acceptor on CH··O and NH··O H-Bond Strength within Proteins. J Phys Chem B 2024; 128:7376-7384. [PMID: 39024061 DOI: 10.1021/acs.jpcb.4c03102] [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: 07/20/2024]
Abstract
The effects of deviations from nonlinearity around the carbonyl proton acceptor of an amide group are assessed by DFT quantum chemical calculations for both CH··O and NH··O H-bonds. The proton donors are the imidazole functional group of His and the indole of Trp, which are paired respectively with N-methylacetamide and acetamide. The displacement of either CH or NH group toward the carbonyl O sp2 lone pairs stabilizes the system and strengthens the H-bond. But the two donor groups differ in their response to a shift out of the amide plane. While the NH··O H-bond is weakened by this displacement, a substantial strengthening is observed when the CH donor is moved out of this plane, in one direction versus the other. This pattern is explained on the basis of simple Coulombic considerations.
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Affiliation(s)
- Steve Scheiner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah 84322-0300, United States
| | - Zygmunt S Derewenda
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, Virginia 22908-0736, United States
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3
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Fiedler J, Trottmann F, Ishida K, Ishida-Ito M, Hertweck C. Direct α-Hydroxy Acid Loading onto a Bacterial Thiotemplate Assembly Line via a Multienzyme Gateway. Angew Chem Int Ed Engl 2024; 63:e202405165. [PMID: 38728443 DOI: 10.1002/anie.202405165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/12/2024]
Abstract
Various nonribosomal peptide synthetases (NRPSs) create structural and functional diversity by incorporating α-hydroxy acids into peptide backbones. Trigonic acid, an unusual cyclopropanol-substituted hydroxy acid, is the source of the molecular warhead of malleicyprol, a critical virulence factor of human and animal pathogens of the Burkholderia pseudomallei (BP) group. The process of selecting and loading this building block remained enigmatic as the NRPS module designated for this task is incomplete. Using a combination of bioinformatics, mutational analyses, targeted metabolomics, and in vitro biochemical assays, we show that two trans-acting enzymes are required to load this central building block onto the modular assembly line. An adenylation-thiolation didomain enzyme (BurJ) activates trigonic acid, followed by the translocation of the enzyme-bound α-hydroxy acid thioester by an FkbH-like protein with a mutated phosphatase domain (BurH). This specialized gateway is the first reported direct loading of an α-hydroxy acid onto a bona fide NRPS module in bacteria and expands the synthetic biology toolbox for the site-specific incorporation of non-canonical building blocks. Moreover, insight into the biochemical basis of virulence factor biosynthesis can provide a foundation for developing enzyme inhibitors as anti-virulence therapeutics against BP pathogen infections.
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Affiliation(s)
- Jonas Fiedler
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Felix Trottmann
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Keishi Ishida
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Mie Ishida-Ito
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
| | - Christian Hertweck
- Department of Biomolecular Chemistry, Leibniz Institute for Natural Product, Research and Infection Biology (HKI), Beutenbergstraße 11a, 07745, Jena, Germany
- Natural Product Chemistry, Faculty of Biological Sciences, Friedrich Schiller University Jena, 07743, Jena, Germany
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4
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Zhang X, Zhang X, Shi H, Zhang H, Zhang J, Yue C, Li D, Yao L, Tang C. Combining Flexible Region Design and Automatic Design to Enhance the Thermal Stability and Catalytic Efficiency of Leucine Dehydrogenase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024. [PMID: 38838197 DOI: 10.1021/acs.jafc.4c02152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Leucine dehydrogenase (LeuDH, EC 1.4.1.9) can reversibly catalyze the oxidative deamination of l-leucine and some other specific α-amino acids to form the corresponding α-ketoacids. This reaction has great significance in the field of food additives and the pharmaceutical industry. The LeuDH from Exiguobacterium sibiricum (EsLeuDH) has high catalytic efficiency but limited thermal stability, hindering its widespread industrial application. In this study, a mutant N5F/I12L/A352Y of EsLeuDH (referred to as M2) was developed with enhanced thermal stability and catalytic activity through rational modification. The M2 mutant exhibits a half-life at 60 °C (t1/2(60 °C)) of 975.7 min and a specific activity of 69.6 U mg-1, which is 5.4 and 2.1 times higher than those of EsLeuDH, respectively. This research may facilitate the utilization of EsLeuDH at elevated temperatures, enhancing its potential for industrial applications. The findings offer a practical and efficient approach for optimizing LeuDH and other industrial enzymes.
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Affiliation(s)
- Xiang Zhang
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Xichuan Zhang
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Hongling Shi
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Huimin Zhang
- College of Animal Science and Technology, Yangzhou University, 88 South Daxue Road, Yangzhou, Jiangsu 225009, People's Republic of China
| | - Jianhui Zhang
- Postdoctoral Innovation Training Base, She Dian Lao Jiu Co. Ltd., 2 Liquor Avenue, Nanyang, Henan 473300, People's Republic of China
| | - Chao Yue
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Dandan Li
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Lunguang Yao
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
| | - Cunduo Tang
- College of Life Science, Nanyang Normal University, 1638 Wolong Road, Nanyang, Henan 473061, People's Republic of China
- Postdoctoral Innovation Training Base, She Dian Lao Jiu Co. Ltd., 2 Liquor Avenue, Nanyang, Henan 473300, People's Republic of China
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5
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Nguyen TTD, Zayed M, Kim YC, Jeong BH. The First Genetic Characterization of the SPRN Gene in Pekin Ducks ( Anas platyrhynchos domesticus). Animals (Basel) 2024; 14:1588. [PMID: 38891635 PMCID: PMC11171214 DOI: 10.3390/ani14111588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 05/24/2024] [Accepted: 05/24/2024] [Indexed: 06/21/2024] Open
Abstract
Prion diseases are fatal neurodegenerative disorders characterized by an accumulation of misfolded prion protein (PrPSc) in brain tissues. The shadow of prion protein (Sho) encoded by the shadow of prion protein gene (SPRN) is involved in prion disease progress. The interaction between Sho and PrP accelerates the PrPSc conversion rate while the SPRN gene polymorphisms have been associated with prion disease susceptibility in several species. Until now, the SPRN gene has not been investigated in ducks. We identified the duck SPRN gene sequence and investigated the genetic polymorphisms of 184 Pekin ducks. We compared the duck SPRN nucleotide sequence and the duck Sho protein amino acid sequence with those of several other species. Finally, we predicted the duck Sho protein structure and the effects of non-synonymous single nucleotide polymorphisms (SNPs) using computational programs. We were the first to report the Pekin duck SPRN gene sequence. The duck Sho protein sequence showed 100% identity compared with the chicken Sho protein sequence. We found 27 novel SNPs in the duck SPRN gene. Four amino acid substitutions were predicted to affect the hydrogen bond distribution in the duck Sho protein structure. Although MutPred2 and SNPs&GO predicted that all non-synonymous polymorphisms were neutral or benign, SIFT predicted that four variants, A22T, G49D, A68T, and M105I, were deleterious. To the best of our knowledge, this is the first report about the genetic and structural characteristics of the duck SPRN gene.
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Affiliation(s)
- Thi-Thuy-Duong Nguyen
- Korea Zoonosis Research Institute, Jeonbuk National University, 820-120, Hana-ro, Iksan 54531, Republic of Korea (M.Z.)
- Department of Bioactive Material Sciences, Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea
| | - Mohammed Zayed
- Korea Zoonosis Research Institute, Jeonbuk National University, 820-120, Hana-ro, Iksan 54531, Republic of Korea (M.Z.)
- Department of Bioactive Material Sciences, Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea
- Department of Surgery, College of Veterinary Medicine, South Valley University, Qena 83523, Egypt
| | - Yong-Chan Kim
- Department of Biological Sciences, Andong National University, Andong 36729, Republic of Korea
| | - Byung-Hoon Jeong
- Korea Zoonosis Research Institute, Jeonbuk National University, 820-120, Hana-ro, Iksan 54531, Republic of Korea (M.Z.)
- Department of Bioactive Material Sciences, Institute for Molecular Biology and Genetics, Jeonbuk National University, Jeonju 54896, Republic of Korea
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6
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Byerly-Duke J, O'Brien EA, Wall BJ, VanVeller B. Thioimidates provide general access to thioamide, amidine, and imidazolone peptide-bond isosteres. Methods Enzymol 2024; 698:27-55. [PMID: 38886036 DOI: 10.1016/bs.mie.2024.04.012] [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] [Indexed: 06/20/2024]
Abstract
Thioamides, amidines, and heterocycles are three classes of modifications that can act as peptide-bond isosteres to alter the peptide backbone. Thioimidate protecting groups can address many of the problematic synthetic issues surrounding installation of these groups. Historically, amidines have received little attention in peptides due to limitations in methods to access them. The first robust and general procedure for the introduction of amidines into peptide backbones exploits the utility of thioimidate protecting groups as a means to side-step reactivity that ultimately renders existing methods unsuitable for the installation of amidines along the main-chain of peptides. Further, amidines formed on-resin can be reacted to form (4H)-imidazolone heteorcycles which have recently been shown to act as cis-amide isosteres. General methods for heterocyclic installation capable of geometrically restricting peptide conformation are also under-developed. This work is significant because it describes a generally applicable and divergent approach to access unexplored peptide designs and architectures.
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Affiliation(s)
- Jacob Byerly-Duke
- Department of Chemistry, Iowa State University, Ames, IA, United States
| | - Emily A O'Brien
- Department of Chemistry, Iowa State University, Ames, IA, United States
| | - Brendan J Wall
- Department of Chemistry, Iowa State University, Ames, IA, United States
| | - Brett VanVeller
- Department of Chemistry, Iowa State University, Ames, IA, United States.
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7
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Byerly-Duke J, VanVeller B. Thioimidate Solutions to Thioamide Problems during Thionopeptide Deprotection. Org Lett 2024; 26:1452-1457. [PMID: 38341867 PMCID: PMC11031844 DOI: 10.1021/acs.orglett.4c00035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2024]
Abstract
Thioamides have structural and chemical similarity to peptide bonds, offering valuable insights when probing peptide backbone interactions, but are prone to side reactions during solid-phase peptide synthesis (SPPS). Thioimidates have been demonstrated to be effective protecting groups for thioamides during peptide elongation. We further demonstrate how thioimidates can assist thioamides through the most yield-crippling step of thionopeptide deprotection, allowing for the first isolation of an important benchmark α-helical peptide that had previously eluded synthesis and isolation.
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Affiliation(s)
- Jacob Byerly-Duke
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Brett VanVeller
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
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8
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Nastasi MR, Borisov VB, Forte E. Membrane-Bound Redox Enzyme Cytochrome bd-I Promotes Carbon Monoxide-Resistant Escherichia coli Growth and Respiration. Int J Mol Sci 2024; 25:1277. [PMID: 38279276 PMCID: PMC10815991 DOI: 10.3390/ijms25021277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/23/2023] [Accepted: 01/18/2024] [Indexed: 01/28/2024] Open
Abstract
The terminal oxidases of bacterial aerobic respiratory chains are redox-active electrogenic enzymes that catalyze the four-electron reduction of O2 to 2H2O taking out electrons from quinol or cytochrome c. Living bacteria often deal with carbon monoxide (CO) which can act as both a signaling molecule and a poison. Bacterial terminal oxidases contain hemes; therefore, they are potential targets for CO. However, our knowledge of this issue is limited and contradictory. Here, we investigated the effect of CO on the cell growth and aerobic respiration of three different Escherichia coli mutants, each expressing only one terminal quinol oxidase: cytochrome bd-I, cytochrome bd-II, or cytochrome bo3. We found that following the addition of CO to bd-I-only cells, a minimal effect on growth was observed, whereas the growth of both bd-II-only and bo3-only strains was severely impaired. Consistently, the degree of resistance of aerobic respiration of bd-I-only cells to CO is high, as opposed to high CO sensitivity displayed by bd-II-only and bo3-only cells consuming O2. Such a difference between the oxidases in sensitivity to CO was also observed with isolated membranes of the mutants. Accordingly, O2 consumption of wild-type cells showed relatively low CO sensitivity under conditions favoring the expression of a bd-type oxidase.
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Affiliation(s)
- Martina R. Nastasi
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy;
| | - Vitaliy B. Borisov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Elena Forte
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy;
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9
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Wang H, Caminati W, Li M, Chen J, Tian X, Grabow JU, Gou Q. n → π* Interaction Enabling Transient Inversion of Chirality. J Phys Chem Lett 2023; 14:8874-8879. [PMID: 37756497 DOI: 10.1021/acs.jpclett.3c02264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
This study reports the observation and characterization of two isomers of the acrolein dimer by using high-resolution rotational spectroscopy in pulsed jets. The first isomer is stabilized by two hydrogen bonds, adopting a planar configuration, and is energetically favored over the second isomer, which exhibits a dominant n → π* interaction in a nearly orthogonal arrangement. Surprisingly, the n → π* interaction was revealed to enable a concerted tunneling motion of two moieties along the carbonyl group. This motion leads to the inversion of transient chirality associated with the exchange of donor-acceptor roles, as revealed by the spectral feature of quadruplets. Inversion of transient chirality is a fundamental phenomenon in quantum mechanics and commonly observed for only inversional motions of protons. It is the first discovery, to the best of our knowledge, that such heavy moieties can also undergo chirality inversion.
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Affiliation(s)
- Hao Wang
- Department of Chemistry School of Chemistry and Chemical Engineering, Chongqing University, No. 55 Daxuecheng South Road Shapingba, Chongqing 401331, China
| | - Walther Caminati
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, Bologna I-40126, Italy
| | - Meng Li
- Institut für Physikalische Chemie & Elektrochemie, Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Junhua Chen
- School of Pharmacy, Guizhou Medical University, Guiyang 550025, Guizhou, China
| | - Xiao Tian
- Department of Chemistry School of Chemistry and Chemical Engineering, Chongqing University, No. 55 Daxuecheng South Road Shapingba, Chongqing 401331, China
| | - Jens-Uwe Grabow
- Institut für Physikalische Chemie & Elektrochemie, Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Qian Gou
- Department of Chemistry School of Chemistry and Chemical Engineering, Chongqing University, No. 55 Daxuecheng South Road Shapingba, Chongqing 401331, China
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10
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Zytkiewicz E, Shkel IA, Cheng X, Rupanya A, McClure K, Karim R, Yang S, Yang F, Record MT. Quantifying Amide-Aromatic Interactions at Molecular and Atomic Levels: Experimentally Determined Enthalpic and Entropic Contributions to Interactions of Amide sp 2O, N, C and sp 3C Unified Atoms with Naphthalene sp 2C Atoms in Water. Biochemistry 2023; 62:2841-2853. [PMID: 37695675 DOI: 10.1021/acs.biochem.3c00367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
In addition to amide hydrogen bonds and the hydrophobic effect, interactions involving π-bonded sp2 atoms of amides, aromatics, and other groups occur in protein self-assembly processes including folding, oligomerization, and condensate formation. These interactions also occur in aqueous solutions of amide and aromatic compounds, where they can be quantified. Previous analysis of thermodynamic coefficients quantifying net-favorable interactions of amide compounds with other amides and aromatics revealed that interactions of amide sp2O with amide sp2N unified atoms (presumably C═O···H-N hydrogen bonds) and amide/aromatic sp2C (lone pair π, n-π*) are particularly favorable. Sp3C-sp3C (hydrophobic), sp3C-sp2C (hydrophobic, CH-π), sp2C-sp2C (hydrophobic, π-π), and sp3C-sp2N interactions are favorable, sp2C-sp2N interactions are neutral, while sp2O-sp2O and sp2N-sp2N self-interactions and sp2O-sp3C interactions are unfavorable. Here, from determinations of favorable effects of 14 amides on naphthalene solubility at 10, 25, and 45 °C, we dissect amide-aromatic interaction free energies into enthalpic and entropic contributions and find these vary systematically with amide composition. Analysis of these results yields enthalpic and entropic contributions to intrinsic strengths of interactions of amide sp2O, sp2N, sp2C, and sp3C unified atoms with aromatic sp2C atoms. For each interaction, enthalpic and entropic contributions have the same sign and are much larger in magnitude than the interaction free energy itself. The amide sp2O-aromatic sp2C interaction is enthalpy-driven and entropically unfavorable, consistent with direct chemical interaction (e.g., lone pair-π), while amide sp3C- and sp2C-aromatic sp2C interactions are entropy-driven and enthalpically unfavorable, consistent with hydrophobic effects. These findings are relevant for interactions involving π-bonded sp2 atoms in protein processes.
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Affiliation(s)
- Emily Zytkiewicz
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Irina A Shkel
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Xian Cheng
- Biophysics Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Anuchit Rupanya
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Kate McClure
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Rezwana Karim
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Sumin Yang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Felix Yang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - M Thomas Record
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Biophysics Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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11
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Zytkiewicz E, Shkel IA, Cheng X, Rupanya A, McClure K, Karim R, Yang S, Yang F, Record MT. Quantifying Amide-Aromatic Interactions at Molecular and Atomic Levels: Experimentally-determined Enthalpic and Entropic Contributions to Interactions of Amide sp 2 O, N, C and sp 3 C Unified Atoms with Naphthalene sp 2 C Atoms in Water. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.12.548600. [PMID: 37503153 PMCID: PMC10370101 DOI: 10.1101/2023.07.12.548600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
In addition to amide hydrogen bonds and the hydrophobic effect, interactions involving π-bonded sp 2 atoms of amides, aromatics and other groups occur in protein self-assembly processes including folding, oligomerization and condensate formation. These interactions also occur in aqueous solutions of amide and aromatic compounds, where they can be quantified. Previous analysis of thermodynamic coefficients quantifying net-favorable interactions of amide compounds with other amides and aromatics revealed that interactions of amide sp 2 O with amide sp 2 N unified atoms (presumably C=O···H-N hydrogen bonds) and amide/aromatic sp 2 C (lone pair-π, n-π * ) are particularly favorable. Sp 3 C-sp 3 C (hydrophobic), sp 3 C-sp 2 C (hydrophobic, CH-π), sp 2 C-sp 2 C (hydrophobic, π-π) and sp 3 C-sp 2 N interactions are favorable, sp 2 C-sp 2 N interactions are neutral, while sp 2 O-sp 2 O and sp 2 N-sp 2 N self-interactions and sp 2 O-sp 3 C interactions are unfavorable. Here, from determinations of favorable effects of fourteen amides on naphthalene solubility at 10, 25 and 45 °C, we dissect amide-aromatic interaction free energies into enthalpic and entropic contributions and find these vary systematically with amide composition. Analysis of these results yields enthalpic and entropic contributions to intrinsic strengths of interactions of amide sp 2 O, sp 2 N, sp 2 C and sp 3 C unified atoms with aromatic sp 2 C atoms. For each interaction, enthalpic and entropic contributions have the same sign and are much larger in magnitude than the interaction free energy itself. The amide sp 2 O-aromatic sp 2 C interaction is enthalpy-driven and entropically unfavorable, consistent with direct chemical interaction (e.g. lone pair-π) while amide sp 3 C- and sp 2 C-aromatic sp 2 C interactions are entropy-driven and enthalpically unfavorable, consistent with hydrophobic effects. These findings are relevant for interactions involving π-bonded sp 2 atoms in protein processes. Table of Contents Graphic
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Affiliation(s)
- Emily Zytkiewicz
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Irina A. Shkel
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Xian Cheng
- Biophysics Program, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Anuchit Rupanya
- Department of Chemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Kate McClure
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Rezwana Karim
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Sumin Yang
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Felix Yang
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - M. Thomas Record
- Department of Biochemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
- Biophysics Program, University of Wisconsin – Madison, Madison, Wisconsin 53706
- Department of Chemistry, University of Wisconsin – Madison, Madison, Wisconsin 53706
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12
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Deka JKR, Borah D, Das P, Sahariah B, Vishnoi P, Sarma BK. Synergistic n → π* and n N → π* Ar interactions in C-terminal modified prolines: effect on Xaa-Pro cis/ trans equilibrium. Chem Commun (Camb) 2023; 59:6080-6083. [PMID: 37128689 DOI: 10.1039/d3cc01494k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Carbonyl-carbonyl (CO⋯CO) n → π* interaction often coexists with a hydrogen bond (HB) or another n → π* interaction. Although the interplay between HB and n → π* interaction was previously studied, there is no systematic investigation that shows a synergistic relationship of n → π* with another noncovalent interaction. Herein, we have studied a set of proline-diacylhydrazine (Pro-DAH) molecules and observed that increase in the strength of the nN → π*Ar interaction on their DAH side strengthened the n → π* interaction on the Pro side, which was experimentally determined by measuring the Ktrans/cis of the Xaa-Pro amide bond. Overall, we describe a simple C-terminal modification strategy to stabilize the trans-Pro geometry that could be useful to stabilize PPII helices and collagen triple helices that require Pro to adopt the trans amide geometry.
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Affiliation(s)
- Jugal Kishore Rai Deka
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
| | - Debashree Borah
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
| | - Paramesh Das
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
| | - Biswajit Sahariah
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
| | - Pratap Vishnoi
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
| | - Bani Kanta Sarma
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
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13
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Panwaria P, Das A. Effect of Substituents on the Intramolecular n→π* Interaction in 3-[2-(Dimethylamino) phenyl] propanal: A Computational Study. J Phys Chem A 2023; 127:3339-3346. [PMID: 37036493 DOI: 10.1021/acs.jpca.2c08641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
n→π* non-covalent interaction (NCI) and hydrogen bond have similarity in terms of delocalization of the electron density between the two orbitals involved in the interaction. Hydrogen bond (X-H···Y) involves delocalization of the lone pair electrons (n) on the Y atom into the σ* orbital of the X-H bond. In contrast, the n→π* interaction deals with delocalizing the lone pair electrons (n) on the N, O, or S atom into the π* orbital of a C═O group or aromatic ring. Herein, we have shown a resemblance of this weak n→π* interaction with the relatively stronger hydrogen bond in terms of folding the side chains in flexible molecules. This work reports the study of folding of the flexible side-chain in 3-[2-(dimethylamino) phenyl] propanal (DMAPhP) through a N···C═O n→π* interaction using various computational approaches such as NBO, QTAIM, and NCI analyses. The folding of the molecule by the n→π* interaction observed in this study is found to be similar to that present in the secondary structures of peptides or proteins through hydrogen bonding interactions. Interestingly, the stabilization of the global minimum conformer of DMAPhP by the n→π* interaction demonstrates the importance of this NCI in providing conformational preferences in molecular systems. Another important finding of this study is that the theoretical redshift obtained in the C═O stretching frequency of the most stable conformer of the DMAPhP is contributed mostly by the n→π* interaction as the C═O group is not involved in hyperconjugation with any neighboring heteroatom, which is a common phenomenon in any ester or amide. We have also demonstrated here that the strength of the intramolecular n→π* interaction can be modulated by varying the electronic substituents at the para position of the donor group involved in the interaction.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
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14
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Kojasoy V, Tantillo DJ. Importance of Noncovalent Interactions Involving Sulfur Atoms in Thiopeptide Antibiotics─Glycothiohexide α and Nocathiacin I. J Phys Chem A 2023; 127:2081-2090. [PMID: 36855831 DOI: 10.1021/acs.jpca.2c07600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Noncovalent interactions involving sulfur atoms play essential roles in protein structure and function by significantly contributing to protein stability, folding, and biological activity. Sulfur is a highly polarizable atom that can participate in many types of noncovalent interactions including hydrogen bonding, sulfur-π interactions, and S-lone pair interactions, but the impact of these sulfur-based interactions on molecular recognition and drug design is still often underappreciated. Here, we examine, using quantum chemical calculations, the roles of sulfur-based noncovalent interactions in complex naturally occurring molecules representative of thiopeptide antibiotics: glycothiohexide α and its close structural analogue nocathiacin I. While donor-acceptor orbital interactions make only very small contributions, electrostatic and dispersion contributions are predicted to be significant in many cases. In pursuit of understanding the magnitudes and nature of these noncovalent interactions, we made potential structural modifications that could significantly expand the chemical space of effective thiopeptide antibiotics.
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Affiliation(s)
- Volga Kojasoy
- Department of Chemistry, University of California─Davis, Davis, California 95616, United States
| | - Dean J Tantillo
- Department of Chemistry, University of California─Davis, Davis, California 95616, United States
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15
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de la Cruz-Martínez F, Bresolí-Obach R, Bravo I, Alonso-Moreno C, Hermida-Merino D, Hofkens J, Lara-Sánchez A, Castro-Osma JA, Martín C. Unexpected luminescence of non-conjugated biomass-based polymers: new approach in photothermal imaging. J Mater Chem B 2023; 11:316-324. [PMID: 36353924 DOI: 10.1039/d2tb02033e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Population growth, depletion of world resources and persistent toxic chemical production underline the need to seek new smart materials from inexpensive, biodegradable, and renewable feedstocks. Hence, "metal-free" ring-opening copolymerization to convert biomass carvone-based monomers into non-conventional luminescent biopolymers is considered a sustainable approach to achieve these goals. The non-conventional emission was studied in terms of steady-state and time-resolved spectroscopy in order to unravel the structure-properties for different carvone-based copolymers. The results highlighted the importance of the final copolymer folding structure as well as its environment in luminescent behavior (cluster-triggered emission). In all cases, their luminescent behavior is sensitive to small temperature fluctuations (where the minimum detected temperature is Tm ∼ 2 °C and relative sensitivity is Sr ∼ 6% °C) even at the microscopic scale, which endows these materials a great potential as thermosensitive smart polymers for photothermal imaging.
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Affiliation(s)
- Felipe de la Cruz-Martínez
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-la Mancha, Avda. Camilo José Cela, 10, Ciudad Real 13071, Spain.
| | - Roger Bresolí-Obach
- Chem&Tech - Molecular Imaging and Photonics, KU Leuven, C/Celestijnenlaan 200F, Leuven 3001, Belgium.,AppLightChem, Institut Quimic de Sarria, Universitat Ramon Lull, Via Augusta 390, Barcelona 08007, Catalunya, Spain
| | - Iván Bravo
- Departamento de Química Física, Facultad de Farmacia, Universidad de Castilla-la Mancha, Avda. Dr. José María Sánchez Ibáñez, s/n, Albacete 02071, Spain.
| | - Carlos Alonso-Moreno
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Farmacia, Universidad de Castilla-la Mancha, Avda. Dr. José María Sánchez Ibáñez, s/n, Albacete 02071, Spain.
| | - Daniel Hermida-Merino
- CINBIO, Departamento de Física Aplicada, Universidade de Vigo, Campus Lagoas-Marcosende, Vigo 36310, Spain
| | - Johan Hofkens
- Chem&Tech - Molecular Imaging and Photonics, KU Leuven, C/Celestijnenlaan 200F, Leuven 3001, Belgium
| | - Agustín Lara-Sánchez
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-la Mancha, Avda. Camilo José Cela, 10, Ciudad Real 13071, Spain.
| | - José A Castro-Osma
- Departamento de Química Inorgánica, Orgánica y Bioquímica-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Farmacia, Universidad de Castilla-la Mancha, Avda. Dr. José María Sánchez Ibáñez, s/n, Albacete 02071, Spain.
| | - Cristina Martín
- Chem&Tech - Molecular Imaging and Photonics, KU Leuven, C/Celestijnenlaan 200F, Leuven 3001, Belgium.,Departamento de Química Física, Facultad de Farmacia, Universidad de Castilla-la Mancha, Avda. Dr. José María Sánchez Ibáñez, s/n, Albacete 02071, Spain.
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16
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Kojasoy V, Tantillo DJ. Impacts of noncovalent interactions involving sulfur atoms on protein stability, structure, folding, and bioactivity. Org Biomol Chem 2022; 21:11-23. [PMID: 36345987 DOI: 10.1039/d2ob01602h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This review discusses the various types of noncovalent interactions in which sulfur atoms participate and their effects on protein stability, structure, folding and bioactivity. Current approaches and recommendations for modelling these noncovalent interactions (in terms of both geometries and interaction energies) are highlighted.
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Affiliation(s)
- Volga Kojasoy
- Department of Chemistry, University of California, Davis, 1 Shields Avenue, Davis, CA, 95616, USA.
| | - Dean J Tantillo
- Department of Chemistry, University of California, Davis, 1 Shields Avenue, Davis, CA, 95616, USA.
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17
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Yabukarski F, Doukov T, Mokhtari DA, Du S, Herschlag D. Evaluating the impact of X-ray damage on conformational heterogeneity in room-temperature (277 K) and cryo-cooled protein crystals. Acta Crystallogr D Struct Biol 2022; 78:945-963. [PMID: 35916220 PMCID: PMC9344472 DOI: 10.1107/s2059798322005939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 06/02/2022] [Indexed: 11/10/2022] Open
Abstract
Cryo-cooling has been nearly universally adopted to mitigate X-ray damage and facilitate crystal handling in protein X-ray crystallography. However, cryo X-ray crystallographic data provide an incomplete window into the ensemble of conformations that is at the heart of protein function and energetics. Room-temperature (RT) X-ray crystallography provides accurate ensemble information, and recent developments allow conformational heterogeneity (the experimental manifestation of ensembles) to be extracted from single-crystal data. Nevertheless, high sensitivity to X-ray damage at RT raises concerns about data reliability. To systematically address this critical issue, increasingly X-ray-damaged high-resolution data sets (1.02–1.52 Å resolution) were obtained from single proteinase K, thaumatin and lysozyme crystals at RT (277 K). In each case a modest increase in conformational heterogeneity with X-ray damage was observed. Merging data with different extents of damage (as is typically carried out) had negligible effects on conformational heterogeneity until the overall diffraction intensity decayed to ∼70% of its initial value. These effects were compared with X-ray damage effects in cryo-cooled crystals by carrying out an analogous analysis of increasingly damaged proteinase K cryo data sets (0.9–1.16 Å resolution). X-ray damage-associated heterogeneity changes were found that were not observed at RT. This property renders it difficult to distinguish real from artefactual conformations and to determine the conformational response to changes in temperature. The ability to acquire reliable heterogeneity information from single crystals at RT, together with recent advances in RT data collection at accessible synchrotron beamlines, provides a strong motivation for the widespread adoption of RT X-ray crystallography to obtain conformational ensemble information.
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18
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Mohamed Yusof NIS, Abdullah ZL, Othman N, Mohd Fauzi F. Structure–Activity Relationship Analysis of Flavonoids and Its Inhibitory Activity Against BACE1 Enzyme Toward a Better Therapy for Alzheimer’s Disease. Front Chem 2022; 10:874615. [PMID: 35832462 PMCID: PMC9271896 DOI: 10.3389/fchem.2022.874615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 05/16/2022] [Indexed: 11/18/2022] Open
Abstract
Drug development in Alzheimer’s disease (AD) suffers from a high attrition rate. In 2021, 117 agents tested in phases I and II and 36 agents tested in phase III were discontinued. Natural product compounds may be good lead compounds for AD as they contain functional groups that are important for binding against key AD targets such as β-secretase enzyme (BACE1). Hence, in this study, 64 flavonoids collected from rigorous literature search and screening that have been tested from 2010 to 2022 against BACE1, which interferes in the formation of amyloid plaque, were analyzed. The 64 unique flavonoids can be further classified into five core fragments. The flavonoids were subjected to clustering analysis based on its structure, and each representative of the clusters was subjected to molecular docking. There were 12 clusters formed, where only 1 cluster contained compounds from two different core fragments. Several observations can be made where 1) flavanones with sugar moieties showed higher inhibitory activity compared to flavanones without sugar moieties. The number of sugar moieties and position of glycosidic linkage may also affect the inhibitory activity. 2) Non-piperazine-substituted chalcones when substituted with functional groups with decreasing electronegativity at the para position of both rings result in a decrease in inhibitory activity. Molecular docking indicates that ring A is involved in hydrogen bond, whereas ring B is involved in van der Waals interaction with BACE1. 3) Hydrogen bond is an important interaction with the catalytic sites of BACE1, which are Asp32 and Asp228. As flavonoids contain favorable structures and properties, this makes them an interesting lead compound for BACE1. However, to date, no flavonoids have made it through clinical trials. Hence, these findings may aid in the design of highly potent and specific BACE1 inhibitors, which could delay the progression of AD.
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Affiliation(s)
| | | | - Norodiyah Othman
- Faculty of Pharmacy, Universiti Teknologi MARA Selangor, Selangor, Malaysia
- Haematology Unit, Cancer Research Centre, Institute for Medical Research, National Institutes of Health Complex, Selangor, Malaysia
| | - Fazlin Mohd Fauzi
- Faculty of Pharmacy, Universiti Teknologi MARA Selangor, Selangor, Malaysia
- Collaborative Drug Discovery Research, Faculty of Pharmacy, Universiti Teknologi MARA Selangor, Selangor, Malaysia
- *Correspondence: Fazlin Mohd Fauzi,
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19
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Zondlo NJ. Solvation stabilizes intercarbonyl n→π* interactions and polyproline II helix. Phys Chem Chem Phys 2022; 24:13571-13586. [PMID: 35635541 DOI: 10.1039/d2cp00857b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
n→π* interactions between consecutive carbonyls stabilize the α-helix and polyproline II helix (PPII) conformations in proteins. n→π* interactions have been suggested to provide significant conformational biases to the disordered states of proteins. To understand the roles of solvation on the strength of n→π* interactions, computational investigations were conducted on a model n→π* interaction, the twisted-parallel-offset formaldehyde dimer, as a function of explicit solvation of the donor and acceptor carbonyls, using water and HF. In addition, the effects of urea, thiourea, guanidinium, and monovalent cations on n→π* interaction strength were examined. Solvation of the acceptor carbonyl significantly strengthens the n→π* interaction, while solvation of the donor carbonyl only modestly weakens the n→π* interaction. The n→π* interaction strength was maximized with two solvent molecules on the acceptor carbonyl. Urea stabilized the n→π* interaction via simultaneous engagement of both oxygen lone pairs on the acceptor carbonyl. Solvent effects were further investigated in the model peptides Ac-Pro-NMe2, Ac-Ala-NMe2, and Ac-Pro2-NMe2. Solvent effects in peptides were similar to those in the formaldehyde dimer, with solvation of the acceptor carbonyl increasing n→π* interaction strength and resulting in more compact conformations, in both the proline endo and exo ring puckers, as well as a reduction in the energy difference between these ring puckers. Carbonyl solvation leads to an energetic preference for PPII over both the α-helix and β/extended conformations, consistent with experimental data that protic solvents and protein denaturants both promote PPII. Solvation of the acceptor carbonyl weakens the intraresidue C5 hydrogen bond that stabilizes the β conformation.
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Affiliation(s)
- Neal J Zondlo
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA.
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20
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Patarroyo MA, Patarroyo ME, Pabón L, Alba MP, Bermudez A, Rugeles MT, Díaz-Arevalo D, Zapata-Builes W, Zapata MI, Reyes C, Suarez CF, Agudelo W, López C, Aza-Conde J, Melo M, Escamilla L, Oviedo J, Guzmán F, Silva Y, Forero M, Flórez-Álvarez L, Aguilar-Jimenez W, Moreno-Vranich A, Garry J, Avendaño C. SM-COLSARSPROT: Highly Immunogenic Supramutational Synthetic Peptides Covering the World's Population. Front Immunol 2022; 13:859905. [PMID: 35693819 PMCID: PMC9175637 DOI: 10.3389/fimmu.2022.859905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/19/2022] [Indexed: 12/02/2022] Open
Abstract
Fifty ~20-amino acid (aa)-long peptides were selected from functionally relevant SARS-CoV-2 S, M, and E proteins for trial B-21 and another 53 common ones, plus some new ones derived from the virus' main genetic variants for complementary trial C-21. Peptide selection was based on tremendous SARS-CoV-2 genetic variability for analysing them concerning vast human immunogenetic polymorphism for developing the first supramutational, Colombian SARS-protection (SM-COLSARSPROT), peptide mixture. Specific physicochemical rules were followed, i.e., aa predilection for polyproline type II left-handed (PPIIL) formation, replacing β-branched, aromatic aa, short-chain backbone H-bond-forming residues, π-π interactions (n→π* and π-CH), aa interaction with π systems, and molecular fragments able to interact with them, disrupting PPIIL propensity formation. All these modified structures had PPIIL formation propensity to enable target peptide interaction with human leukocyte antigen-DRβ1* (HLA-DRβ1*) molecules to mediate antigen presentation and induce an appropriate immune response. Such modified peptides were designed for human use; however, they induced high antibody titres against S, M, and E parental mutant peptides and neutralising antibodies when suitably modified and chemically synthesised for immunising 61 major histocompatibility complex class II (MHCII) DNA genotyped Aotus monkeys (matched with their corresponding HLA-DRβ1* molecules), predicted to cover 77.5% to 83.1% of the world's population. Such chemically synthesised peptide mixture represents an extremely pure, stable, reliable, and cheap vaccine for COVID-19 pandemic control, providing a new approach for a logical, rational, and soundly established methodology for other vaccine development.
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Affiliation(s)
- Manuel A. Patarroyo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Manuel E. Patarroyo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Laura Pabón
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Martha P. Alba
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Adriana Bermudez
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - María Teresa Rugeles
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
| | - Diana Díaz-Arevalo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Wildeman Zapata-Builes
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
| | - María Isabel Zapata
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
| | - César Reyes
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Carlos F. Suarez
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - William Agudelo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Carolina López
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Jorge Aza-Conde
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Miguel Melo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Luis Escamilla
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Jairo Oviedo
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Fanny Guzmán
- Núcleo de Biotecnología, Pontificia U. Católica de Valparaíso, Valparaíso, Chile
| | - Yolanda Silva
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Martha Forero
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Lizdany Flórez-Álvarez
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
| | - Wbeimar Aguilar-Jimenez
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
| | - Armando Moreno-Vranich
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Jason Garry
- Grupos: Síntesis Química, Resonancia Magnética Nuclear y Cálculo Estructural, Biología Molecular e Inmunología e Inmuno-Química, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
| | - Catalina Avendaño
- Facultad de Ciencias Agropecualrias, Universidad de Ciencias Aplicadas y Ambientales (UDCA), Bogotá, Colombia
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21
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Chen J, Wang H, Zheng Y, Zhang X, Xu X, Gou Q. Sp 2- and sp 3-C⋯O tetrel bonds in the 3-oxetanone homodimer. Phys Chem Chem Phys 2022; 24:8992-8998. [PMID: 35380142 DOI: 10.1039/d2cp00703g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The structures and non-covalent interactions at play in the 3-oxetanone homodimer have been investigated using a pulsed jet Fourier transform microwave spectrometer supplemented with quantum chemical calculations. Two isomers were identified in the pulsed jet. With the analyses of non-covalent intermolecular interactions including the quantum theory of atoms, Johnson's non-covalent interactions and natural bond orbital, the observed global minimum is stabilized by a combination of one sp2-C⋯O tetrel bond and a network of multiple C-H⋯O weak hydrogen bonds. The second isomer is characterized by carbonyl-carbonyl interactions, with the formation of one sp2- and one sp3-C⋯O tetrel bond. The conformational population of the two observed isomers in the supersonic expansion was estimated to be NCE1/NCC1 ≈ 7/5.
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Affiliation(s)
- Junhua Chen
- School of Pharmacy, Guizhou Medical University, Guiyang 550000, Guizhou, China.,Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
| | - Hao Wang
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
| | - Yang Zheng
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
| | - Xinyue Zhang
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
| | - Xuefang Xu
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
| | - Qian Gou
- Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China. .,Chongqing Key Laboratory of Theoretical and Computational Chemistry, Daxuecheng South Rd. 55, 401331, Chongqing, China
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22
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Ethyl 5-Formyl-1-(pyridin-3-yl)-1H-1,2,3-triazole-4-carboxylate: Synthesis, Crystal Structure, Hirshfeld Surface Analysis, and DFT Calculation. MOLBANK 2022. [DOI: 10.3390/m1340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
For the first time, 5-formyl-1-(pyridin-3-yl)-1H-1,2,3-triazole-4-carboxylate was synthesized via a two-step scheme. The molecular structure of the compound was determined by a single-crystal X-ray diffraction analysis. The Hirshfeld surface analysis was used to study various intermolecular interactions. The crystalline structure is marked by the presence of three types of π-interactions (n→π*, lp···π, and π···π) between the -C(H)=O group and triazole rings. The compound is a versatile polyfunctional building block for construction of annulated 1,2,3-triazoles.
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23
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Chalana A, Kumar Rai R, Karri R, Kumar Jha K, Kumar B, Roy G. Interplay of the intermolecular and intramolecular interactions in stabilizing the thione-based copper(I) complexes and their significance in protecting the biomolecules against metal-mediated oxidative damage. Polyhedron 2022. [DOI: 10.1016/j.poly.2021.115647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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24
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Vik EC, Li P, Madukwe DO, Karki I, Tibbetts GS, Shimizu KD. Analysis of the Orbital and Electrostatic Contributions to the Lone Pair-Aromatic Interaction Using Molecular Rotors. Org Lett 2021; 23:8179-8182. [PMID: 34670094 DOI: 10.1021/acs.orglett.1c02878] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The attractive interaction between carbonyl oxygens and the π-face of aromatic surfaces was studied using N-phenylimide molecular rotors. The C═O···Ar interactions could stabilize the transition states but were half the strength of comparable C═O···C═O interactions. The C═O···Ar interaction had a significant electrostatic component but only a small orbital delocalization component.
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Affiliation(s)
- Erik C Vik
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Ping Li
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Daniel O Madukwe
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Ishwor Karki
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Gabriel S Tibbetts
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
| | - Ken D Shimizu
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, United States
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25
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Henderson WR, Liu G, Abboud KA, Castellano RK. Tuning Supramolecular Polymer Assembly through Stereoelectronic Interactions. J Am Chem Soc 2021; 143:12688-12698. [PMID: 34346675 DOI: 10.1021/jacs.1c05522] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The supramolecular polymerization of 2,11-dithia[3.3]paracyclophanes through self-complementary intermolecular and transannular amide hydrogen bonding is presented. An n → π* interaction between the amide hydrogen bonding units and the central bridging atom results from the single-point exchange of a carbon atom for a sulfur atom. This orbital donor-acceptor interaction can be strengthened by oxidizing the sulfide to a sulfone which acts to shorten the donor···acceptor distance and increase orbital overlap. Experimental signatures of the increased n → π* interaction include larger isodesmic polymerization elongation constants in solution, changes in characteristic bond stretching frequencies, and geometric/structural changes evaluated by X-ray crystallography. The experimental data are supported by extensive computational investigations of both assembling and nonassembling 2,11-dithia[3.3]paracyclophanes as well as a rationally designed model system to confirm the role of stereoelectronic effects on supramolecular polymer assembly.
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Affiliation(s)
- Will R Henderson
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Guancen Liu
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Khalil A Abboud
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
| | - Ronald K Castellano
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States
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26
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Dongre AV, Das S, Bellur A, Kumar S, Chandrashekarmath A, Karmakar T, Balaram P, Balasubramanian S, Balaram H. Structural basis for the hyperthermostability of an archaeal enzyme induced by succinimide formation. Biophys J 2021; 120:3732-3746. [PMID: 34302792 DOI: 10.1016/j.bpj.2021.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 06/18/2021] [Accepted: 07/19/2021] [Indexed: 10/20/2022] Open
Abstract
Stability of proteins from hyperthermophiles (organisms existing under boiling water conditions) enabled by a reduction of conformational flexibility is realized through various mechanisms. A succinimide (SNN) arising from the post-translational cyclization of the side chains of aspartyl/asparaginyl residues with the backbone amide -NH of the succeeding residue would restrain the torsion angle Ψ and can serve as a new route for hyperthermostability. However, such a succinimide is typically prone to hydrolysis, transforming to either an aspartyl or β-isoaspartyl residue. Here, we present the crystal structure of Methanocaldococcus jannaschii glutamine amidotransferase and, using enhanced sampling molecular dynamics simulations, address the mechanism of its increased thermostability, up to 100°C, imparted by an unexpectedly stable succinimidyl residue at position 109. The stability of SNN109 to hydrolysis is seen to arise from its electrostatic shielding by the side-chain carboxylate group of its succeeding residue Asp110, as well as through n → π∗ interactions between SNN109 and its preceding residue Glu108, both of which prevent water access to SNN. The stable succinimidyl residue induces the formation of an α-turn structure involving 13-atom hydrogen bonding, which locks the local conformation, reducing protein flexibility. The destabilization of the protein upon replacement of SNN with a Φ-restricted prolyl residue highlights the specificity of the succinimidyl residue in imparting hyperthermostability to the enzyme. The conservation of the succinimide-forming tripeptide sequence (E(N/D)(E/D)) in several archaeal GATases strongly suggests an adaptation of this otherwise detrimental post-translational modification as a harbinger of thermostability.
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Affiliation(s)
- Aparna Vilas Dongre
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sudip Das
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Asutosh Bellur
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Sanjeev Kumar
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India; National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| | - Anusha Chandrashekarmath
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India
| | - Tarak Karmakar
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India; Department of Chemistry and Applied Biosciences, ETH Zurich, Lugano, Ticino, Switzerland; Facoltà di Informatica, Istituto di Scienze Computationali, Università della Svizzera Italiana, Lugano, Ticino, Switzerland
| | - Padmanabhan Balaram
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India; Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
| | - Sundaram Balasubramanian
- Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India.
| | - Hemalatha Balaram
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, India.
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27
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Nagesh J. Cross-Talk between Overlap Interactions in Biomolecules: A Case Study of the β-Turn Motif. Molecules 2021; 26:1533. [PMID: 33799657 PMCID: PMC7998147 DOI: 10.3390/molecules26061533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 11/30/2022] Open
Abstract
Noncovalent interactions play a pivotal role in regulating protein conformation, stability and dynamics. Among the quantum mechanical (QM) overlap-based noncovalent interactions, n→π* is the best understood with studies ranging from small molecules to β-turns of model proteins such as GB1. However, these investigations do not explore the interplay between multiple overlap interactions in contributing to local structure and stability. In this work, we identify and characterize all noncovalent overlap interactions in the β-turn, an important secondary structural element that facilitates the folding of a polypeptide chain. Invoking a QM framework of natural bond orbitals, we demonstrate the role of several additional interactions such as n→σ* and π→π* that are energetically comparable to or larger than n→π*. We find that these interactions are sensitive to changes in the side chain of the residues in the β-turn of GB1, suggesting that the n→π* may not be the only component in dictating β-turn conformation and stability. Furthermore, a database search of n→σ* and π→π* in the PDB reveals that they are prevalent in most proteins and have significant interaction energies (∼1 kcal/mol). This indicates that all overlap interactions must be taken into account to obtain a comprehensive picture of their contributions to protein structure and energetics. Lastly, based on the extent of QM overlaps and interaction energies, we propose geometric criteria using which these additional interactions can be efficiently tracked in broad database searches.
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Affiliation(s)
- Jayashree Nagesh
- Solid State and Structural Chemistry Unit, Indian Institute of Science Bangalore, Bengaluru 560012, Karnataka, India
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28
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Guclu TF, Atilgan AR, Atilgan C. Dynamic Community Composition Unravels Allosteric Communication in PDZ3. J Phys Chem B 2021; 125:2266-2276. [PMID: 33631929 DOI: 10.1021/acs.jpcb.0c11604] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The third domain of PSD-95 (PDZ3) is a model for investigating allosteric communication in protein and ligand interactions. While motifs contributing to its binding specificity have been scrutinized, a conformational dynamical basis is yet to be established. Despite the miniscule structural changes due to point mutants, the observed significant binding affinity differences have previously been assessed with a focus on two α-helices located at the binding groove (α2) and the C-terminus (α3). Here, we employ a new computational approach to develop a generalized view on the molecular basis of PDZ3 binding selectivity and interaction communication for a set of point mutants of the protein (G330T, H372A, G330T-H372A) and its ligand (CRIPT, named L1, and its T-2F variant, L2) along with the wild type (WT). To analyze the dynamical aspects hidden in the conformations that are produced by molecular dynamics simulations, we utilize variations in community composition calculated based on the betweenness centrality measure from graph theory. We find that the highly charged N-terminus, which is located far from the ligand, has the propensity to share the same community with the ligand in the biologically functional complexes, indicating a distal segment might mediate the binding dynamics. N- and C-termini of PDZ3 share communities, and α3 acts as a hub for the whole protein by sustaining the communication with all structural segments, albeit being a trait not unique to the functional complexes. Moreover, α2 which lines the binding cavity frequently parts communities with the ligand and is not a controller of the binding but is rather a slave to the overall dynamics coordinated by the N-terminus. Thus, ligand binding fate in PDZ3 is traced to the population of community compositions extracted from dynamics despite the lack of significant conformational changes.
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Affiliation(s)
- Tandac F Guclu
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
| | - Ali Rana Atilgan
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
| | - Canan Atilgan
- Faculty of Engineering and Natural Sciences, Sabanci University, 34956, Istanbul, Turkey
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29
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Verma N, Tao Y, Kraka E. Systematic Detection and Characterization of Hydrogen Bonding in Proteins via Local Vibrational Modes. J Phys Chem B 2021; 125:2551-2565. [DOI: 10.1021/acs.jpcb.0c11392] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Niraj Verma
- Department of Chemistry, Southern Methodist University, Dallas Texas United States
| | - Yunwen Tao
- Department of Chemistry, Southern Methodist University, Dallas Texas United States
| | - Elfi Kraka
- Department of Chemistry, Southern Methodist University, Dallas Texas United States
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30
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Sahariah B, Sarma BK. Spectroscopic evidence of n → π* interactions involving carbonyl groups. Phys Chem Chem Phys 2021; 22:26669-26681. [PMID: 33226050 DOI: 10.1039/d0cp03557b] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
n → π* has emerged as an important noncovalent interaction that can affect the conformations of both small- and macromolecules including peptides and proteins. Carbonyl-carbonyl (COCO) n → π* interactions involving CO groups are well studied. Recent studies have shown that the COCO n → π* interactions are the most abundant secondary interactions in proteins with a frequency of 33 interactions per 100 residues and, among the various secondary interactions, n → π* interactions are expected to provide the highest enthalpic contributions to the conformational stability of globular proteins. However, n → π* interactions are relatively weak and provide an average stabilization of about 0.25 kcal mol-1 per interaction in proteins. The strongest n → π* interaction could be as strong as a moderate hydrogen bond. Therefore, it is challenging to detect and quantify these weak interactions, especially in solution in the presence of perturbation from other intermolecular interactions. Accordingly, spectroscopic investigations that can provide direct evidence of n → π* interaction are limited, and the majority of papers published in this area have relied on X-ray crystallography and/or theoretical calculations to establish the presence of this interaction. The aim of this perspective is to discuss the studies where a spectroscopic signature in support of n → π* interaction was observed. As the "n → π* interaction" is a relatively new terminology, there remains the possibility of there being earlier studies where spectroscopic evidence for n → π* interactions was obtained but it was not discussed in light of the n → π* terminology. We noticed several such studies and, as can be expected, these studies were often overlooked in the discussion of n → π* interactions in the recent literature. In this perspective, we have also discussed these studies and provided computational support for the presence of n → π* interaction.
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Affiliation(s)
- Biswajit Sahariah
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
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31
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Tang WK, Mu X, Li M, Martens J, Berden G, Oomens J, Chu IK, Siu CK. Formation of n → π + interaction facilitating dissociative electron transfer in isolated tyrosine-containing molecular peptide radical cations. Phys Chem Chem Phys 2021; 22:21393-21402. [PMID: 32940309 DOI: 10.1039/d0cp00533a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Long-range electron transfer in proteins can be rationalized as a sequential short-distance electron-hopping processes via amino acid residues having low ionization energy as relay stations. Tyrosine residues can serve as such redox-active intermediates through one-electron oxidation to form a π-radical cation at its phenol side chain. An electron transfer from a vicinal functional group to this π-electron hole completes an elementary step of charge migration. However, transient oxidized/reduced intermediates formed at those relay stations during electron transfer processes have not been observed. In this study, formation of analog reactive intermediates via electron donor-acceptor coupling is observed by using IRMPD action spectroscopy. An elementary charge migration at the molecular level in model tyrosine-containing peptide radical cations [M]˙+ in the gas phase is revealed with its unusual Cα-Cβ bond cleavage at the side chain of the N-terminal residue. This reaction is induced by the radical character of the N-terminal amino group (-NH2˙+) resulting from an n → π+ interaction between the nonbonding electron pair of NH2 (n) and the π-electron hole at the Tyr side chain (π+). The formation of -NH2˙+ is supported by the IRMPD spectrum showing a characteristic NH2 scissor vibration coupled with Tyr side-chain stretches at 1577 cm-1. This n → π+ interaction facilitates a dissociative electron transfer with NH2 as the relay station. The occurrence of this side-chain cleavage may be an indicator of the formation of reactive conformers featuring the n → π+ interaction.
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Affiliation(s)
- Wai Kit Tang
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China.
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32
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Vennelakanti V, Qi HW, Mehmood R, Kulik HJ. When are two hydrogen bonds better than one? Accurate first-principles models explain the balance of hydrogen bond donors and acceptors found in proteins. Chem Sci 2021; 12:1147-1162. [PMID: 35382134 PMCID: PMC8908278 DOI: 10.1039/d0sc05084a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/18/2020] [Indexed: 01/02/2023] Open
Abstract
Hydrogen bonds (HBs) play an essential role in the structure and catalytic action of enzymes, but a complete understanding of HBs in proteins challenges the resolution of modern structural (i.e., X-ray diffraction) techniques and mandates computationally demanding electronic structure methods from correlated wavefunction theory for predictive accuracy. Numerous amino acid sidechains contain functional groups (e.g., hydroxyls in Ser/Thr or Tyr and amides in Asn/Gln) that can act as either HB acceptors or donors (HBA/HBD) and even form simultaneous, ambifunctional HB interactions. To understand the relative energetic benefit of each interaction, we characterize the potential energy surfaces of representative model systems with accurate coupled cluster theory calculations. To reveal the relationship of these energetics to the balance of these interactions in proteins, we curate a set of 4000 HBs, of which >500 are ambifunctional HBs, in high-resolution protein structures. We show that our model systems accurately predict the favored HB structural properties. Differences are apparent in HBA/HBD preference for aromatic Tyr versus aliphatic Ser/Thr hydroxyls because Tyr forms significantly stronger O–H⋯O HBs than N–H⋯O HBs in contrast to comparable strengths of the two for Ser/Thr. Despite this residue-specific distinction, all models of residue pairs indicate an energetic benefit for simultaneous HBA and HBD interactions in an ambifunctional HB. Although the stabilization is less than the additive maximum due both to geometric constraints and many-body electronic effects, a wide range of ambifunctional HB geometries are more favorable than any single HB interaction. Correlated wavefunction theory predicts and high-resolution crystal structure analysis confirms the important, stabilizing effect of simultaneous hydrogen bond donor and acceptor interactions in proteins.![]()
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Affiliation(s)
- Vyshnavi Vennelakanti
- Department of Chemical Engineering
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Chemistry
| | - Helena W. Qi
- Department of Chemical Engineering
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Chemistry
| | - Rimsha Mehmood
- Department of Chemical Engineering
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Chemistry
| | - Heather J. Kulik
- Department of Chemical Engineering
- Massachusetts Institute of Technology
- Cambridge
- USA
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33
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Chatterjee D, Pakhira M, Nandi AK. Fluorescence in "Nonfluorescent" Polymers. ACS OMEGA 2020; 5:30747-30766. [PMID: 33324785 PMCID: PMC7726791 DOI: 10.1021/acsomega.0c04700] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 11/16/2020] [Indexed: 05/04/2023]
Abstract
Recently, a great deal of research has been started on generating fairly strong photoluminescence from organic molecules without having any conjugated π-system or fluorophore. Discrete chromophores or auxochromophores termed as "subfluorophores" may undergo "space conjugation" via co-operative intramolecular conformation followed by intermolecular aggregation to generate fluorescence or sometimes phosphorescence emission. Polymeric materials are important in this regard as nonconjugated polymers self-assemble/aggregate in a moderately concentrated solution and also in the solid state, producing membranes, films, and so forth with good physical and mechanical properties. Therefore, promoting fluorescence in these commodity polymers is very much useful for sensing, organic light emitting diodes (OLED), and biological applications. In this perspective, we have discussed the aggregation-induced emission from four different types of architectures, for example, (i) dendrimers or hyperbranched polymers, (ii) entrapped polymeric micellar self-assembly, (iii) cluster formation, and (iv) stretching-induced aggregation, begining with the genesis of fluorescence from aggregation of propeller-shaped small organic molecules. The mechanism of induced fluorescence of polymers with subfluorophoric groups is also discussed from the theoretical calculations of the energy bands in the aggregated state. Also, an attempt has been made to highlight some useful applications in the sensing of surfactants, bacteria, cell imaging, drug delivery, gene delivery, OLED, and so forth.
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Affiliation(s)
- Dhruba
P. Chatterjee
- Department
of Chemistry, Presidency University, 86/1 College Street, Kolkata 700 073, India
| | - Mahuya Pakhira
- Polymer Science
Unit, School of Materials Science, Indian
Association for the Cultivation of Science, Jadavpur, Kolkata 700
032, India
| | - Arun K. Nandi
- Polymer Science
Unit, School of Materials Science, Indian
Association for the Cultivation of Science, Jadavpur, Kolkata 700
032, India
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34
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Cheng X, Shkel IA, O'Connor K, Record MT. Experimentally determined strengths of favorable and unfavorable interactions of amide atoms involved in protein self-assembly in water. Proc Natl Acad Sci U S A 2020; 117:27339-27345. [PMID: 33087561 PMCID: PMC7959557 DOI: 10.1073/pnas.2012481117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Folding and other protein self-assembly processes are driven by favorable interactions between O, N, and C unified atoms of the polypeptide backbone and side chains. These processes are perturbed by solutes that interact with these atoms differently than water does. Amide NH···O=C hydrogen bonding and various π-system interactions have been better characterized structurally or by simulations than experimentally in water, and unfavorable interactions are relatively uncharacterized. To address this situation, we previously quantified interactions of alkyl ureas with amide and aromatic compounds, relative to interactions with water. Analysis yielded strengths of interaction of each alkylurea with unit areas of different hybridization states of unified O, N, and C atoms of amide and aromatic compounds. Here, by osmometry, we quantify interactions of 10 pairs of amides selected to complete this dataset. An analysis yields intrinsic strengths of six favorable and four unfavorable atom-atom interactions, expressed per unit area of each atom and relative to interactions with water. The most favorable interactions are sp2O-sp2C (lone pair-π, presumably n-π*), sp2C-sp2C (π-π and/or hydrophobic), sp2O-sp2N (hydrogen bonding) and sp3C-sp2C (CH-π and/or hydrophobic). Interactions of sp3C with itself (hydrophobic) and with sp2N are modestly favorable, while sp2N interactions with sp2N and with amide/aromatic sp2C are modestly unfavorable. Amide sp2O-sp2O interactions and sp2O-sp3C interactions are more unfavorable, indicating the preference of amide sp2O to interact with water. These intrinsic interaction strengths are used to predict interactions of amides with proteins and chemical effects of amides (including urea, N-ethylpyrrolidone [NEP], and polyvinylpyrrolidone [PVP]) on protein stability.
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Affiliation(s)
- Xian Cheng
- Program in Biophysics, University of Wisconsin-Madison, Madison, WI 53706
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Irina A Shkel
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Kevin O'Connor
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - M Thomas Record
- Program in Biophysics, University of Wisconsin-Madison, Madison, WI 53706;
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706
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35
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Kilgore HR, Olsson CR, D’Angelo KA, Movassaghi M, Raines RT. n→π* Interactions Modulate the Disulfide Reduction Potential of Epidithiodiketopiperazines. J Am Chem Soc 2020; 142:15107-15115. [PMID: 32701272 PMCID: PMC7484275 DOI: 10.1021/jacs.0c06477] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Epithiodiketopiperazines (ETPs) are a structurally complex class of fungal natural products with potent anticancer activity. In ETPs, the diketopiperazine ring is spanned by a disulfide bond that is constrained in a high-energy eclipsed conformation. We employed computational, synthetic, and spectroscopic methods to investigate the physicochemical attributes of this atypical disulfide bond. We find that the disulfide bond is stabilized by two n→π* interactions, each with large energies (3-5 kcal/mol). The n→π* interactions in ETPs make disulfide reduction much more difficult, endowing stability in physiological environments in a manner that could impact their biological activity. These data reveal a previously unappreciated means to stabilize a disulfide bond and highlight the utility of the n→π* interaction in molecular design.
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Affiliation(s)
| | | | - Kyan A. D’Angelo
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mohammad Movassaghi
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ronald T. Raines
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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36
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Khatri B, Majumder P, Nagesh J, Penmatsa A, Chatterjee J. Increasing protein stability by engineering the n → π* interaction at the β-turn. Chem Sci 2020; 11:9480-9487. [PMID: 34094214 PMCID: PMC8161691 DOI: 10.1039/d0sc03060k] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Abundant n → π* interactions between adjacent backbone carbonyl groups, identified by statistical analysis of protein structures, are predicted to play an important role in dictating the structure of proteins. However, experimentally testing the prediction in proteins has been challenging due to the weak nature of this interaction. By amplifying the strength of the n → π* interaction via amino acid substitution and thioamide incorporation at a solvent exposed β-turn within the GB1 proteins and Pin 1 WW domain, we demonstrate that an n → π* interaction increases the structural stability of proteins by restricting the ϕ torsion angle. Our results also suggest that amino acid side-chain identity and its rotameric conformation play an important and decisive role in dictating the strength of an n → π* interaction. Amino acid residues adopt a right-handed α-helical conformation with increasing strength of the n → π* interaction. We also demonstrate a direct consequence of n → π* interactions on enhancing the structural stability of proteins.![]()
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Affiliation(s)
- Bhavesh Khatri
- Molecular Biophysics Unit, Indian Institute of Science Bangalore 560012 India
| | - Puja Majumder
- Molecular Biophysics Unit, Indian Institute of Science Bangalore 560012 India
| | - Jayashree Nagesh
- Solid State and Structural Chemistry Unit, Indian Institute of Science Bangalore India
| | - Aravind Penmatsa
- Molecular Biophysics Unit, Indian Institute of Science Bangalore 560012 India
| | - Jayanta Chatterjee
- Molecular Biophysics Unit, Indian Institute of Science Bangalore 560012 India
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37
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Kia R, Kalaghchi A. Intra- and intermolecular interactions in a series of chlorido-tricarbonyl-diazabutadienerhenium(I) complexes: structural and theoretical studies. ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2020; 76:417-426. [PMID: 32831260 DOI: 10.1107/s2052520620004333] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 03/30/2020] [Indexed: 06/11/2023]
Abstract
A series of new chlorido-tricarbonylrhenium(I) complexes bearing alkyl-substituted diazabutadiene (DAB) ligands, namely N,N'-bis(2,4-dimethylbenzene)-1,4-diazabutadiene (L1), N,N'-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene (L2), N,N'-bis(2,4,6-trimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene (L3) and N,N'-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene (L4), were synthesized and investigated. The crystal structures have been fully characterized by X-ray diffraction and spectroscopic methods. Density functional theory, natural bond orbital and non-covalent interaction index methods have been used to study the optimized geometry in the gas phase and intra- and intermolecular interactions in the complexes, respectively. The most important studied interactions in these metal carbonyl complexes are n→π*, n→σ* and π→π*. Among complexes 1-4, only 2 shows interesting intermolecular n→π* interactions due to lp(C[triple-bond]O)...π* and lp(Cl)...π* (lp = lone pair) contacts.
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Affiliation(s)
- Reza Kia
- Department of Chemistry, Sharif University of Technology, Tehran, 11155-3516, Iran
| | - Azadeh Kalaghchi
- Department of Chemistry, Sharif University of Technology, Tehran, 11155-3516, Iran
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Sarkar S, Ramanathan N, Sruthi P, Sundararajan K. Computational and experimental evidence of N–H…π and cooperative πN…π∗ interactions in pyrrole…benzene and pyrrole…ethylene heterodimers at low temperatures. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.127983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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39
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Zhao G, Zhu H. Cation-π Interactions in Graphene-Containing Systems for Water Treatment and Beyond. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1905756. [PMID: 32253804 DOI: 10.1002/adma.201905756] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 01/30/2020] [Indexed: 06/11/2023]
Abstract
Cation-π interactions are common in nature, especially in organisms. Their profound influences in chemistry, physics, and biology have been continuously investigated since they were discovered in 1981. However, the importance of cation-π interactions in materials science, regarding carbonaceous nanomaterials, has just been realized. The interplay between cations and delocalized polarizable π electrons of graphene would bring about significant changes to the intrinsic characteristics of graphene and greatly affect the device performance based on graphene and its derivatives. Here, the cation-π interactions in graphene containing systems for water treatment applications (e.g., separation membranes, adsorbents) are highlighted. The cross-linking effects caused by cation-π interactions contribute to membrane stability and selectivity and enhanced adsorption. Their roles in dominating the performance of graphene-based structures for other specific applications are also discussed. Relevant theoretical modeling and calculations are summarized to offer an in-depth understanding of the underlying mechanisms which can help in designing more functional materials and structures. Perspectives on the potential directions that deserve effort are also presented.
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Affiliation(s)
- Guoke Zhao
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Hongwei Zhu
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
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40
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Structural, Non-Covalent Interaction, and Natural Bond Orbital Studies on Bromido-Tricarbonyl Rhenium(I) Complexes Bearing Alkyl-Substituted 1,4-Diazabutadiene (DAB) Ligands. CRYSTALS 2020. [DOI: 10.3390/cryst10040267] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene, 2,4-Me2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene, 2,4-Me2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene, 2,4,6-Me3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene, 2,6-ipr2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR, 1H-NMR, 13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each complex, the Re(I) centre shows a distorted octahedral shape with a facial geometry of carbonyl groups. The gas phase geometry of the complexes was identified by density functional theory. Interesting intermolecular n…π* interactions of complexes 1 and 3 were investigated by non-covalent interaction index (NCI), and natural bond orbital (NBO) analyses. The intramolecular n…σ*, σ…π*, π…σ* interactions were also studied in complexes 3 and 4.
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41
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Filippova AA, Kerner AA, Znoiko SA, Tikhomirova TV, Vashurin AS. Aggregation and Molecular Complexation of Bifunctionally Substituted Cobalt Phthalocyaninates in Aqueous Media. RUSS J INORG CHEM+ 2020. [DOI: 10.1134/s0036023620020047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Nagpal U, Kamalesh D, Raghuraman P, Ramireddy S, Sudandiradoss C. Delineating the folding perturbations and molecular mechanisms of Thr-Ala 642 mutation in Rab-GTPase activating protein Akt substrate of 160kDa and its impact on the aetiology of diabetes. J Biomol Struct Dyn 2020; 39:409-420. [DOI: 10.1080/07391102.2020.1726814] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Utkarsh Nagpal
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamilnadu, India
| | - D. Kamalesh
- Department of Integrative Biology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamilnadu, India
| | - P. Raghuraman
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamilnadu, India
| | - Sriroopreddy Ramireddy
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamilnadu, India
| | - C. Sudandiradoss
- Department of Biotechnology, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, Tamilnadu, India
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43
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Kia R, Taghavi T, Raithby PR. Supramolecular assembly through intermolecular n → π* interactions through a coordinated perrhenate formed via superoxidation of Re( i) to Re( vii) in the formation of substituted Re(CO) 3 complexes bearing Diimine ligands. CrystEngComm 2020. [DOI: 10.1039/d0ce01073a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Two Re(i) tricarbonyl complexes bearing Ph4TAP and dafone ligands and having a coordinated perrhenate group obtained via in situ superoxidation of Re(i) to Re(vii) have been characterized.
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Affiliation(s)
- Reza Kia
- Chemistry Department
- Sharif University of Technology
- Tehran
- Iran
| | - Tahereh Taghavi
- Chemistry Department
- Sharif University of Technology
- Tehran
- Iran
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Deka JKR, Sahariah B, Baruah K, Bar AK, Sarma BK. Conformational control of N-methyl-N,N′-diacylhydrazines by noncovalent carbon bonding in solution. Chem Commun (Camb) 2020; 56:4874-4877. [DOI: 10.1039/d0cc00943a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Unusual N(amide)⋯C–X noncovalent carbon bonding interactions stabilize the trans–cis (t–c) amide bond rotamers of N-methyl-N,N′-diacylhydrazines over the expected trans–trans (t–t) rotamers in solution.
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Affiliation(s)
| | - Biswajit Sahariah
- Department of Chemistry
- School of Natural Sciences
- Shiv Nadar University
- Dadri
- India
| | - Kalpita Baruah
- Department of Chemistry
- School of Natural Sciences
- Shiv Nadar University
- Dadri
- India
| | - Arun Kumar Bar
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER) Tirupati
- Tirupati 517507
- India
| | - Bani Kanta Sarma
- New Chemistry Unit
- Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR)
- Bangalore 560064
- India
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45
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Kia R. Non-covalent sulfoxide⋯(nitrosyl group) interactions involving coordinated nitrosyl in a Ru( ii) nitrosyl complex with an α-diimine ligand: structural and computational studies. CrystEngComm 2020. [DOI: 10.1039/d0ce01063d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Inspection of the X-ray structure of the newly prepared Ru–nitrosyl complex bearing an α-diimine ligand revealed for the first time the π-hole interaction involving the coordinated nitrosyl group with DMSO.
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Affiliation(s)
- Reza Kia
- Chemistry Department
- Sharif University of Technology
- Tehran
- Iran
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46
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Rees GJ, Day SP, Barnsley KE, Iuga D, Yates JR, Wallis JD, Hanna JV. Measuring multiple 17O–13C J-couplings in naphthalaldehydic acid: a combined solid state NMR and density functional theory approach. Phys Chem Chem Phys 2020; 22:3400-3413. [DOI: 10.1039/c9cp03977e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A combined multinuclear solid-state NMR and a density functional theory computational approach, with SIMPSON simulations, is evaluated to determine the four heteronuclear 1J(13C,17O) couplings in naphthalaldehydic acid.
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Affiliation(s)
| | | | | | - Dinu Iuga
- Department of Physics
- University of Warwick
- Coventry
- UK
| | | | - John D. Wallis
- School of Science and Technology
- Nottingham Trent University
- Nottingham
- UK
| | - John V. Hanna
- Department of Physics
- University of Warwick
- Coventry
- UK
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47
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Arias-Olivares D, Wieduwilt EK, Contreras-García J, Genoni A. NCI-ELMO: A New Method To Quickly and Accurately Detect Noncovalent Interactions in Biosystems. J Chem Theory Comput 2019; 15:6456-6470. [DOI: 10.1021/acs.jctc.9b00658] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- David Arias-Olivares
- Doctorado en Fisicoquímica Molecular, Facultad de Ciencias Exactas, Universidad Andrés Bello, Ave. Republica 275, Santiago, Chile
- Sorbonne Université & CNRS, Laboratoire de Chimie Théorique, UMR CNRS 7616, 4 Place Jussieu, F-75005 Paris, France
| | - Erna K. Wieduwilt
- Université de Lorraine & CNRS, Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, 1 Boulevard Arago, F-57078 Metz, France
| | - Julia Contreras-García
- Sorbonne Université & CNRS, Laboratoire de Chimie Théorique, UMR CNRS 7616, 4 Place Jussieu, F-75005 Paris, France
| | - Alessandro Genoni
- Université de Lorraine & CNRS, Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, 1 Boulevard Arago, F-57078 Metz, France
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Singh SK, Panwaria P, Mishra KK, Das A. Steric as well as n→π* Interaction Controls the Conformational Preferences of Phenyl Acetate: Gas‐phase Spectroscopy and Quantum Chemical Calculations. Chem Asian J 2019; 14:4705-4711. [DOI: 10.1002/asia.201901158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/03/2019] [Indexed: 01/26/2023]
Affiliation(s)
- Santosh K. Singh
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
- Current Address: Department of ChemistryUniversity of Hawaii, Manoa Honolulu Hawaii 96822 USA
| | - Prakash Panwaria
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Kamal K. Mishra
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Aloke Das
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
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Abstract
A complete inventory of the forces governing protein folding is critical for productive protein modeling, including structure prediction and de novo design, as well as understanding protein misfolding diseases of clinical significance. The dominant contributors to protein folding include the hydrophobic effect and conventional hydrogen bonding, along with Coulombic and van der Waals interactions. Over the past few decades, important additional contributors have been identified, including C-H···O hydrogen bonding, n→π* interactions, C5 hydrogen bonding, chalcogen bonding, and interactions involving aromatic rings (cation-π, X-H···π, π-π, anion-π, and sulfur-arene). These secondary contributions fall into two general classes: (1) weak but abundant interactions of the protein main chain and (2) strong but less frequent interactions involving protein side chains. Though interactions with high individual energies play important roles in specifying nonlocal molecular contacts and ligand binding, we estimate that weak but abundant interactions are likely to make greater overall contributions to protein folding, particularly at the level of secondary structure. Further research is likely to illuminate additional roles of these noncanonical interactions and could also reveal contributions yet unknown.
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Affiliation(s)
| | - Ronald T. Raines
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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50
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Mehmood R, Qi HW, Steeves AH, Kulik HJ. The Protein’s Role in Substrate Positioning and Reactivity for Biosynthetic Enzyme Complexes: The Case of SyrB2/SyrB1. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00865] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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