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Pill MF, East ALL, Marx D, Beyer MK, Clausen‐Schaumann H. Mechanical Activation Drastically Accelerates Amide Bond Hydrolysis, Matching Enzyme Activity. Angew Chem Int Ed Engl 2019; 58:9787-9790. [DOI: 10.1002/anie.201902752] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/10/2019] [Indexed: 01/21/2023]
Affiliation(s)
- Michael F. Pill
- Department of Applied Sciences and MechatronicsMunich University of Applied Sciences Lothstrasse 34 80334 Munich Germany
- Center for Nanoscience (CeNS) Schellingstrasse 4 80799 Munich Germany
| | - Allan L. L. East
- Department of Chemistry and BiochemistryUniversity of Regina Regina SK S4S0A2 Canada
| | - Dominik Marx
- Lehrstuhl für Theoretische ChemieRuhr-Universität Bochum 44780 Bochum Germany
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstrasse 25 6020 Innsbruck Austria
| | - Hauke Clausen‐Schaumann
- Department of Applied Sciences and MechatronicsMunich University of Applied Sciences Lothstrasse 34 80334 Munich Germany
- Center for Nanoscience (CeNS) Schellingstrasse 4 80799 Munich Germany
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Pill MF, East ALL, Marx D, Beyer MK, Clausen‐Schaumann H. Mechanische Aktivierung beschleunigt die Hydrolyse der Amidbindung drastisch, vergleichbar der Aktivität von Enzymen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902752] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Michael F. Pill
- Fakultät für angewandte Naturwissenschaften und MechatronikHochschule für angewandte Wissenschaften München Lothstraße 34 80334 München Deutschland
- Center for Nanoscience (CeNS) Schellingstraße 4 80799 München Deutschland
| | - Allan L. L. East
- Department of Chemistry and BiochemistryUniversity of Regina Regina SK S4S0A2 Kanada
| | - Dominik Marx
- Lehrstuhl für Theoretische ChemieRuhr-Universität Bochum 44780 Bochum Deutschland
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
| | - Hauke Clausen‐Schaumann
- Fakultät für angewandte Naturwissenschaften und MechatronikHochschule für angewandte Wissenschaften München Lothstraße 34 80334 München Deutschland
- Center for Nanoscience (CeNS) Schellingstraße 4 80799 München Deutschland
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Affiliation(s)
- Allan L. L. East
- Department of Chemistry and Biochemistry; University of Regina; Regina Canada
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Mallick A, Xu Y, Lin Y, He J, Chan-Park MB, Liu XW. Oxadiazabicyclooctenone as a versatile monomer for the construction of pH sensitive functional polymers via ROMP. Polym Chem 2018. [DOI: 10.1039/c7py01413a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Herein, oxadiazabicyclooctenone is successfully developed as a versatile monomer for the construction of new pH-sensitive polymers by ROMP.
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Affiliation(s)
- Asadulla Mallick
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
| | - Yuan Xu
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
| | - Yichao Lin
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
| | - Jingxi He
- Centre of Antimicrobial Bioengineering
- School of Chemical and Biomedical Engineering
- NTU
- Singapore 637459
| | - Mary B. Chan-Park
- Centre of Antimicrobial Bioengineering
- School of Chemical and Biomedical Engineering
- NTU
- Singapore 637459
| | - Xue-Wei Liu
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
- Centre of Antimicrobial Bioengineering
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5
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Varga MJ, Dzierlenga MW, Schwartz SD. Structurally Linked Dynamics in Lactate Dehydrogenases of Evolutionarily Distinct Species. Biochemistry 2017; 56:2488-2496. [PMID: 28445027 DOI: 10.1021/acs.biochem.7b00245] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We present new findings about how primary and secondary structure affects the role of fast protein motions in the reaction coordinates of enzymatic reactions. Using transition path sampling and committor distribution analysis, we examined the difference in the role of these fast protein motions in the reaction coordinate of lactate dehydrogenases (LDHs) of Apicomplexa organisms Plasmodium falciparum and Cryptosporidium parvum. Having evolved separately from a common malate dehydrogenase ancestor, the two enzymes exhibit several important structural differences, notably a five-amino acid insertion in the active site loop of P. falciparum LDH. We find that these active site differences between the two organisms' LDHs likely cause a decrease in the contribution of the previously determined LDH rate-promoting vibration to the reaction coordinate of P. falciparum LDH compared to that of C. parvum LDH, specifically in the coupling of the rate-promoting vibration and the hydride transfer. This effect, while subtle, directly shows how changes in structure near the active site of LDH alter catalytically important motions. Insights provided by studying these alterations would prove to be useful in identifying LDH inhibitors that specifically target the isozymes of these parasitic organisms.
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Affiliation(s)
- Matthew J Varga
- Department of Chemistry and Biochemistry, University of Arizona , 1306 East University Boulevard, Tucson, Arizona 85721, United States
| | - Michael W Dzierlenga
- Department of Chemistry and Biochemistry, University of Arizona , 1306 East University Boulevard, Tucson, Arizona 85721, United States
| | - Steven D Schwartz
- Department of Chemistry and Biochemistry, University of Arizona , 1306 East University Boulevard, Tucson, Arizona 85721, United States
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Decrey L, Kazama S, Kohn T. Ammonia as an In Situ Sanitizer: Influence of Virus Genome Type on Inactivation. Appl Environ Microbiol 2016; 82:4909-20. [PMID: 27260358 PMCID: PMC4968548 DOI: 10.1128/aem.01106-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/26/2016] [Indexed: 01/16/2023] Open
Abstract
UNLABELLED Treatment of human excreta and animal manure (HEAM) is key in controlling the spread of persistent enteric pathogens, such as viruses. The extent of virus inactivation during HEAM storage and treatment appears to vary with virus genome type, although the reasons for this variability are not clear. Here, we investigated the inactivation of viruses of different genome types under conditions representative of HEAM storage or mesophilic digestion. The goals were to characterize the influence of HEAM solution conditions on inactivation and to determine the potential mechanisms involved. Specifically, eight viruses representing the four viral genome types (single-stranded RNA [ssRNA], double-stranded RNA [dsRNA], single-stranded DNA [ssDNA], and double-stranded DNA [dsDNA]) were exposed to synthetic solutions with well-controlled temperature (20 to 35°C), pH (8 to 9), and ammonia (NH3) concentrations (0 to 40 mmol liter(-1)). DNA and dsRNA viruses were considerably more resistant than ssRNA viruses, resulting in up to 1,000-fold-longer treatment times to reach a 4-log inactivation. The apparently slower inactivation of DNA viruses was rationalized by the higher stability of DNA than that of ssRNA in HEAM. Pushing the system toward harsher pH (>9) and temperature (>35°C) conditions, such as those encountered in thermophilic digestion and alkaline treatments, led to more consistent inactivation kinetics among ssRNA and other viruses. This suggests that the dependence of inactivation on genome type disappeared in favor of protein-mediated inactivation mechanisms common to all viruses. Finally, we recommend the use of MS2 as a conservative indicator to assess the inactivation of ssRNA viruses and the stable ΦX174 or dsDNA phages as indicators for persistent viruses. IMPORTANCE Viruses are among the most environmentally persistent pathogens. They can be present in high concentrations in human excreta and animal manure (HEAM). Therefore, appropriate treatment of HEAM is important prior to its reuse or discharge into the environment. Here, we investigated the factors that determine the persistence of viruses in HEAM, and we determined the main mechanisms that lead to their inactivation. Unlike other organisms, viruses can have four different genome types (double- or single-stranded RNA or DNA), and the viruses studied herein represent all four types. Genome type appeared to be the major determinant for persistence. Single-stranded RNA viruses are the most labile, because this genome type is susceptible to degradation in HEAM. In contrast, the other genome types are more stable; therefore, inactivation is slower and mainly driven by the degradation of viral proteins. Overall, this study allows us to better understand the behavior of viruses in HEAM.
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Affiliation(s)
- Loïc Decrey
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Shinobu Kazama
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland New Industry Creation Hatchery Center (NICHe), Sendai, Miyagi, Japan
| | - Tamar Kohn
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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Dzierlenga MW, Varga MJ, Schwartz SD. Path Sampling Methods for Enzymatic Quantum Particle Transfer Reactions. Methods Enzymol 2016; 578:21-43. [PMID: 27497161 PMCID: PMC5026240 DOI: 10.1016/bs.mie.2016.05.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The mechanisms of enzymatic reactions are studied via a host of computational techniques. While previous methods have been used successfully, many fail to incorporate the full dynamical properties of enzymatic systems. This can lead to misleading results in cases where enzyme motion plays a significant role in the reaction coordinate, which is especially relevant in particle transfer reactions where nuclear tunneling may occur. In this chapter, we outline previous methods, as well as discuss newly developed dynamical methods to interrogate mechanisms of enzymatic particle transfer reactions. These new methods allow for the calculation of free energy barriers and kinetic isotope effects (KIEs) with the incorporation of quantum effects through centroid molecular dynamics (CMD) and the full complement of enzyme dynamics through transition path sampling (TPS). Recent work, summarized in this chapter, applied the method for calculation of free energy barriers to reaction in lactate dehydrogenase (LDH) and yeast alcohol dehydrogenase (YADH). We found that tunneling plays an insignificant role in YADH but plays a more significant role in LDH, though not dominant over classical transfer. Additionally, we summarize the application of a TPS algorithm for the calculation of reaction rates in tandem with CMD to calculate the primary H/D KIE of YADH from first principles. We found that the computationally obtained KIE is within the margin of error of experimentally determined KIEs and corresponds to the KIE of particle transfer in the enzyme. These methods provide new ways to investigate enzyme mechanism with the inclusion of protein and quantum dynamics.
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Affiliation(s)
| | - M J Varga
- University of Arizona, Tucson, AZ, United States
| | - S D Schwartz
- University of Arizona, Tucson, AZ, United States.
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Varga MJ, Schwartz SD. Enzymatic Kinetic Isotope Effects from First-Principles Path Sampling Calculations. J Chem Theory Comput 2016; 12:2047-54. [PMID: 26949835 DOI: 10.1021/acs.jctc.5b01169] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this study, we develop and test a method to determine the rate of particle transfer and kinetic isotope effects in enzymatic reactions, specifically yeast alcohol dehydrogenase (YADH), from first-principles. Transition path sampling (TPS) and normal mode centroid dynamics (CMD) are used to simulate these enzymatic reactions without knowledge of their reaction coordinates and with the inclusion of quantum effects, such as zero-point energy and tunneling, on the transferring particle. Though previous studies have used TPS to calculate reaction rate constants in various model and real systems, it has not been applied to a system as large as YADH. The calculated primary H/D kinetic isotope effect agrees with previously reported experimental results, within experimental error. The kinetic isotope effects calculated with this method correspond to the kinetic isotope effect of the transfer event itself. The results reported here show that the kinetic isotope effects calculated from first-principles, purely for barrier passage, can be used to predict experimental kinetic isotope effects in enzymatic systems.
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Affiliation(s)
- Matthew J Varga
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Steven D Schwartz
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
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Dopieralski P, Ribas-Arino J, Anjukandi P, Krupicka M, Marx D. Force-Induced Reversal of β-Eliminations: Stressed Disulfide Bonds in Alkaline Solution. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201508005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Przemyslaw Dopieralski
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
- Faculty of Chemistry; University of Wroclaw; Joliot-Curie 14 50-383 Wroclaw Poland
| | - Jordi Ribas-Arino
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
- Departament de Química Física and IQTCUB; Universitat de Barcelona; Av. Diagonal 645 08028 Barcelona Spain
| | - Padmesh Anjukandi
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
| | - Martin Krupicka
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
- Max-Planck-Institut für Chemische Energiekonversion; Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
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Dopieralski P, Ribas-Arino J, Anjukandi P, Krupicka M, Marx D. Force-Induced Reversal of β-Eliminations: Stressed Disulfide Bonds in Alkaline Solution. Angew Chem Int Ed Engl 2015; 55:1304-8. [PMID: 26634891 DOI: 10.1002/anie.201508005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 11/04/2015] [Indexed: 12/17/2022]
Abstract
Understanding the impact of tensile forces on disulfide bond cleavage is not only crucial to the breaking of cross-linkers in vulcanized materials such as strained rubber, but also to the regulation of protein activity by disulfide switches. By using ab initio simulations in the condensed phase, we investigated the response of disulfide cleavage by β-elimination to mechanical stress. We reveal that the rate-determining first step of the thermal reaction, which is the abstraction of the β-proton, is insensitive to external forces. However, forces larger than about 1 nN were found to reshape the free-energy landscape of the reaction so dramatically that a second channel is created, where the order of the reaction steps is reversed, turning β-deprotonation into a barrier-free follow-up process to C-S cleavage. This transforms a slow and force-independent process with second-order kinetics into a unimolecular reaction that is greatly accelerated by mechanical forces.
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Affiliation(s)
- Przemyslaw Dopieralski
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany. .,Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383, Wroclaw, Poland.
| | - Jordi Ribas-Arino
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany. .,Departament de Química Física and IQTCUB, Universitat de Barcelona, Av. Diagonal 645, 08028, Barcelona, Spain.
| | - Padmesh Anjukandi
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany
| | - Martin Krupicka
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany.,Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany.
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Gräter F, Li W. Transition path sampling with quantum/classical mechanics for reaction rates. Methods Mol Biol 2015; 1215:27-45. [PMID: 25330957 DOI: 10.1007/978-1-4939-1465-4_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Predicting rates of biochemical reactions through molecular simulations poses a particular challenge for two reasons. First, the process involves bond formation and/or cleavage and thus requires a quantum mechanical (QM) treatment of the reaction center, which can be combined with a more efficient molecular mechanical (MM) description for the remainder of the system, resulting in a QM/MM approach. Second, reaction time scales are typically many orders of magnitude larger than the (sub-)nanosecond scale accessible by QM/MM simulations. Transition path sampling (TPS) allows to efficiently sample the space of dynamic trajectories from the reactant to the product state without an additional biasing potential. We outline here the application of TPS and QM/MM to calculate rates for biochemical reactions, by means of a simple toy system. In a step-by-step protocol, we specifically refer to our implementation within the MD suite Gromacs, which we have made available to the research community, and include practical advice on the choice of parameters.
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Affiliation(s)
- Frauke Gräter
- Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, Heidelberg, 69118, Germany,
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Pill MF, Schmidt SW, Beyer MK, Clausen-Schaumann H, Kersch A. A density functional theory model of mechanically activated silyl ester hydrolysis. J Chem Phys 2015; 140:044321. [PMID: 25669537 DOI: 10.1063/1.4862827] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
To elucidate the mechanism of the mechanically activated dissociation of chemical bonds between carboxymethylated amylose (CMA) and silane functionalized silicon dioxide, we have investigated the dissociation kinetics of the bonds connecting CMA to silicon oxide surfaces with density functional calculations including the effects of force, solvent polarizability, and pH. We have determined the activation energies, the pre-exponential factors, and the reaction rate constants of candidate reactions. The weakest bond was found to be the silyl ester bond between the silicon and the alkoxy oxygen atom. Under acidic conditions, spontaneous proton addition occurs close to the silyl ester such that neutral reactions become insignificant. Upon proton addition at the most favored position, the activation energy for bond hydrolysis becomes 31 kJ mol(-1), which agrees very well with experimental observation. Heterolytic bond scission in the protonated molecule has a much higher activation energy. The experimentally observed bi-exponential rupture kinetics can be explained by different side groups attached to the silicon atom of the silyl ester. The fact that different side groups lead to different dissociation kinetics provides an opportunity to deliberately modify and tune the kinetic parameters of mechanically activated bond dissociation of silyl esters.
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Affiliation(s)
- Michael F Pill
- Department of Applied Sciences and Mechatronics, Munich University of Applied Sciences, Lothstr. 34, 80335 Munich, Germany
| | - Sebastian W Schmidt
- Department of Applied Sciences and Mechatronics, Munich University of Applied Sciences, Lothstr. 34, 80335 Munich, Germany
| | - Martin K Beyer
- Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Olshausenstraße 40, 24098 Kiel, Germany
| | - Hauke Clausen-Schaumann
- Department of Applied Sciences and Mechatronics, Munich University of Applied Sciences, Lothstr. 34, 80335 Munich, Germany
| | - Alfred Kersch
- Department of Applied Sciences and Mechatronics, Munich University of Applied Sciences, Lothstr. 34, 80335 Munich, Germany
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13
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Li Y, Sheiko SS. Molecular Mechanochemistry: Engineering and Implications of Inherently Strained Architectures. Top Curr Chem (Cham) 2015; 369:1-36. [PMID: 25805145 DOI: 10.1007/128_2015_627] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Mechanical activation of chemical bonds is usually achieved by applying external forces. However, nearly all molecules exhibit inherent strain of their chemical bonds and angles as a result of constraints imposed by covalent bonding and interactions with the surrounding environment. Particularly strong deformation of bonds and angles is observed in hyperbranched macromolecules caused by steric repulsion of densely grafted polymer branches. In addition to the tension amplification, macromolecular architecture allows for accurate control of strain distribution, which enables focusing of the internal mechanical tension to specific chemical bonds and angles. As such, chemically identical bonds in self-strained macromolecules become physically distinct because the difference in bond tension leads to the corresponding difference in the electronic structure and chemical reactivity of individual bonds within the same macromolecule. In this review, we outline different approaches to the design of strained macromolecules along with physical principles of tension management, including generation, amplification, and focusing of mechanical tension at specific chemical bonds.
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Affiliation(s)
- Yuanchao Li
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27599-3290, USA
| | - Sergei S Sheiko
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27599-3290, USA.
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Model studies of force-dependent kinetics of multi-barrier reactions. Nat Commun 2014; 4:2538. [PMID: 24077443 DOI: 10.1038/ncomms3538] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 09/03/2013] [Indexed: 12/22/2022] Open
Abstract
According to transition state theory, the rate of a reaction that traverses multiple energy barriers is determined by the least stable (rate-determining) transition state. The preceding ('inner') energy barriers are kinetically 'invisible' but mechanistically significant. Here we show experimentally and computationally that the reduction rate of organic disulphides by phosphines in water, which in the absence of force proceeds by an equilibrium formation of a thiophosphonium intermediate, measured as a function of force applied on the disulphide moiety yields a usefully accurate estimate of the height of the inner barrier. We apply varying stretching force to the disulphide by incorporating it into a series of increasingly strained macrocycles. This force accelerates the reduction, even though the strain-free rate-determining step is orthogonal to the pulling direction. The observed rate-force correlation is consistent with the simplest model of force-dependent kinetics of a multi-barrier reaction.
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Akbulatov S, Tian Y, Kapustin E, Boulatov R. Model Studies of the Kinetics of Ester Hydrolysis under Stretching Force. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300746] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Akbulatov S, Tian Y, Kapustin E, Boulatov R. Model studies of the kinetics of ester hydrolysis under stretching force. Angew Chem Int Ed Engl 2013; 52:6992-5. [PMID: 23686750 DOI: 10.1002/anie.201300746] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 04/23/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Sergey Akbulatov
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK
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17
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Recovery and characterization of proteinacious material recovered from thermal and alkaline hydrolyzed specified risk materials. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.04.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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