1
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Saito S. Unraveling the dynamic slowdown in supercooled water: The role of dynamic disorder in jump motions. J Chem Phys 2024; 160:194506. [PMID: 38767263 DOI: 10.1063/5.0209713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/01/2024] [Indexed: 05/22/2024] Open
Abstract
When a liquid is rapidly cooled below its melting point without inducing crystallization, its dynamics slow down significantly without noticeable structural changes. Elucidating the origin of this slowdown has been a long-standing challenge. Here, we report a theoretical investigation into the mechanism of the dynamic slowdown in supercooled water, a ubiquitous yet extraordinary substance characterized by various anomalous properties arising from local density fluctuations. Using molecular dynamics simulations, we found that the jump dynamics, which are elementary structural change processes, deviate from Poisson statistics with decreasing temperature. This deviation is attributed to slow variables competing with the jump motions, i.e., dynamic disorder. The present analysis of the dynamic disorder showed that the primary slow variable is the displacement of the fourth nearest oxygen atom of a jumping molecule, which occurs in an environment created by the fluctuations of molecules outside the first hydration shell. As the temperature decreases, the jump dynamics become slow and intermittent. These intermittent dynamics are attributed to the prolonged trapping of jumping molecules within extended and stable low-density domains. As the temperature continues to decrease, the number of slow variables increases due to the increased cooperative motions. Consequently, the jump dynamics proceed in a higher-dimensional space consisting of multiple slow variables, becoming slower and more intermittent. It is then conceivable that with further decreasing temperature, the slowing and intermittency of the jump dynamics intensify, eventually culminating in a glass transition.
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Affiliation(s)
- Shinji Saito
- Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan and The Graduate University for Advanced Studies (SOKENDAI), Myodaiji, Okazaki, Aichi 444-8585, Japan
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2
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Kundu P, Saha S, Gangopadhyay G. A minimal kinetic model for the interpretation of complex catalysis in single enzyme molecules. Phys Chem Chem Phys 2023; 26:463-476. [PMID: 38078459 DOI: 10.1039/d3cp01720f] [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: 12/22/2023]
Abstract
Multi-exponential waiting-time distribution and randomness parameter greater than unity ascribe dynamic disorder in single-enzyme catalysis corroborated to the interplay of transforming conformers [English et al., Nat. Chem. Biol., 2006, 2, 87]. The associated multi-state model of enzymatic turnovers with statically heterogeneous catalytic rates misdescribes the non-linear uprising of the randomness parameter from unity in relation to the attributes of the fall-offs of the waiting-time distribution at different substrate concentrations. To resolve this crucial issue, we first employ a comprehensive stochastic reaction scenario and further rationalize and work out the minimal indispensable dynamic-disorder model that ensures the foregoing relationship upon comparison with the data. We elucidate that specific disregard for the transition rate coefficients in the multi-state model on account of the especially slow conformational transitions is the underlying reason for not achieving interrelation between the observables.
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Affiliation(s)
- Prasanta Kundu
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Soma Saha
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata 700073, India.
| | - Gautam Gangopadhyay
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
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3
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Chaudhury S, Jangid P, Kolomeisky AB. Dynamics of chemical reactions on single nanocatalysts with heterogeneous active sites. J Chem Phys 2023; 158:074101. [PMID: 36813720 DOI: 10.1063/5.0137751] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Modern chemical science and industries critically depend on the application of various catalytic methods. However, the underlying molecular mechanisms of these processes still remain not fully understood. Recent experimental advances that produced highly-efficient nanoparticle catalysts allowed researchers to obtain more quantitative descriptions, opening the way to clarify the microscopic picture of catalysis. Stimulated by these developments, we present a minimal theoretical model that investigates the effect of heterogeneity in catalytic processes at the single-particle level. Using a discrete-state stochastic framework that accounts for the most relevant chemical transitions, we explicitly evaluated the dynamics of chemical reactions on single heterogeneous nanocatalysts with different types of active sites. It is found that the degree of stochastic noise in nanoparticle catalytic systems depends on several factors that include the heterogeneity of catalytic efficiencies of active sites and distinctions between chemical mechanisms on different active sites. The proposed theoretical approach provides a single-molecule view of heterogeneous catalysis and also suggests possible quantitative routes to clarify some important molecular details of nanocatalysts.
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Affiliation(s)
- Srabanti Chaudhury
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008, India
| | - Pankaj Jangid
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008, India
| | - Anatoly B Kolomeisky
- Department of Chemistry, Department of Physics and Astronomy, Department of Chemical and Biomolecular Engineering and Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005-1892, USA
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4
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An S, Patel P, Liu C, Skodje RT. Computational Aspects of Single-Molecule Kinetics for Coupled Catalytic Cycles: A Spectral Analysis. J Phys Chem A 2022; 126:3783-3796. [PMID: 35658508 DOI: 10.1021/acs.jpca.2c02153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Catalysis from single active sites is analyzed using methods developed from single-molecule kinetics. Using a stochastic Markov-state description, the observable properties of general catalytic networks of reactions are expressed using an eigenvalue decomposition of the transition matrix for the Markov process. By the use of a sensitivity analysis, the necessary eigenvalues and eigenvectors are related to the energies of controlling barriers and wells located along the reaction routes. A generalization of the energetic span theory allows the eigenvalues to be computed from several activation energies corresponding to distinct barrier-well pairings. The formalism is demonstrated for model problems and for a physically realistic mechanism for an alkene hydrogenation reaction on a single-atom catalyst. The spectral analysis permits a hierarchy of timescales to be identified from the single-molecule signal, which correspond to specific relaxation modes in the network.
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Affiliation(s)
- Suming An
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - Prajay Patel
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60639, United States
| | - Cong Liu
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60639, United States
| | - Rex T Skodje
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
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5
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Lim H, Jung Y. Reaction-path statistical mechanics of enzymatic kinetics. J Chem Phys 2022; 156:134108. [PMID: 35395879 DOI: 10.1063/5.0075831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We introduce a reaction-path statistical mechanics formalism based on the principle of large deviations to quantify the kinetics of single-molecule enzymatic reaction processes under the Michaelis-Menten mechanism, which exemplifies an out-of-equilibrium process in the living system. Our theoretical approach begins with the principle of equal a priori probabilities and defines the reaction path entropy to construct a new nonequilibrium ensemble as a collection of possible chemical reaction paths. As a result, we evaluate a variety of path-based partition functions and free energies by using the formalism of statistical mechanics. They allow us to calculate the timescales of a given enzymatic reaction, even in the absence of an explicit boundary condition that is necessary for the equilibrium ensemble. We also consider the large deviation theory under a closed-boundary condition of the fixed observation time to quantify the enzyme-substrate unbinding rates. The result demonstrates the presence of a phase-separation-like, bimodal behavior in unbinding events at a finite timescale, and the behavior vanishes as its rate function converges to a single phase in the long-time limit.
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Affiliation(s)
- Hyuntae Lim
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
| | - YounJoon Jung
- Department of Chemistry, Seoul National University, Seoul 08826, South Korea
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6
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Kim K, Song S, Sung J. Non‐steady‐state enzyme reaction dynamics. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Kyungwoo Kim
- Department of Chemistry and Institute of Innovative Functional Imaging Chung‐Ang University Seoul South Korea
| | - Sanggeun Song
- Department of Chemistry and Institute of Innovative Functional Imaging Chung‐Ang University Seoul South Korea
| | - Jaeyoung Sung
- Department of Chemistry and Institute of Innovative Functional Imaging Chung‐Ang University Seoul South Korea
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7
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Punia B, Chaudhury S, Kolomeisky AB. Understanding the Reaction Dynamics on Heterogeneous Catalysts Using a Simple Stochastic Approach. J Phys Chem Lett 2021; 12:11802-11810. [PMID: 34860518 DOI: 10.1021/acs.jpclett.1c03557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Recent experimental advances on investigating nanoparticle catalysts with multiple active sites provided a large amount of quantitative information on catalytic processes. These observations stimulated significant theoretical efforts, but the underlying molecular mechanisms are still not well-understood. We introduce a simple theoretical method to analyze the reaction dynamics on catalysts with multiple active sites based on a discrete-state stochastic description and obtain a comprehensive description of the dynamics of chemical reactions on such catalysts. We explicitly determine how the dynamics of catalyzed chemical reactions depend on the number of active sites, on the number of intermediate chemical transitions, and on the topology of underlying chemical reactions. It is argued that the theory provides quantitative bounds for realistic dynamic properties of catalytic processes that can be directly applied to analyze the experimental observations. In addition, this theoretical approach clarifies several important aspects of the molecular mechanisms of chemical reactions on catalysts.
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Affiliation(s)
- Bhawakshi Punia
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, Maharashtra, India
| | - Srabanti Chaudhury
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, Maharashtra, India
| | - A B Kolomeisky
- Department of Chemistry and Center for Theoretical Biological Physics, Department of Chemical and Biomolecular Engineering, Department of Physics and Astronomy, Rice University, Houston, Texas 77005-1892, United States
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8
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Kundu P, Saha S, Gangopadhyay G. A Revisit to Turnover Kinetics of Individual Escherichia coli β-Galactosidase Molecules. J Phys Chem B 2021; 125:8010-8020. [PMID: 34270240 DOI: 10.1021/acs.jpcb.1c04299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Single-molecule experiments on β-galactosidase from Escherichia coli that catalyzes the hydrolysis of resorufin-β-d-galactopyranoside revealed important observations like fluctuating catalytic rate, memory effects arising from temporal correlations between the enzymatic turnovers and nonexponential waiting time distributions. The root cause of the observed results is intrinsic fluctuations among the different conformers of the active species, during the course of the reaction, thereby imparting dynamic disorder in the system under investigation. Originally, a multistate stochastic kinetic theory was employed that, despite satisfying the measured waiting time distributions and the mean waiting times at different substrate concentrations, yields a constant estimate of the randomness parameter. Inevitably, this manifests a strong disagreement with the substrate-concentration-dependent time variations of the said distribution, which at the same time misinterprets the measured magnitudes of the randomness parameter at lower concentrations. Here, we suggest a dual approach to the single-enzyme reaction, independently, making important improvements over the parent study and the recently suggested two-state stochastic analyses followed by quantitative rationalization of the experimental data. In the first case, an off-pathway mechanism satisfied the Michaelis-Menten equation under the circumstance of prevailing disorder while tested against the single-molecule data. However, recovery of randomness data in the lower-concentration regime, albeit primarily marks a significant refinement, a qualitative agreement at the growing concentrations seems to be reasoned by an account of switching among the limited numbers of discrete conformers. Consequently, in the second case, we circumvented the conventional way of approaching the enzyme catalysis and mapped the dynamics of structural transitions of the biocatalyst with the temporal fluctuations of the spatial distance between the different locations along a coarse-grained polymer chain. Exploiting a general mechanism for dynamic disorder, a reaction-diffusion formalism yielded an analytical expression for the waiting time distribution of the enzymatic turnovers, from which the mean waiting time and the randomness parameter were readily determined. Application of our results to the findings of the experiment on single β-galactosidase shows a quantitative agreement in each case. This soundly validates the usefulness of accounting for a more rigorous microscopic description pertinent to the conformational multiplicity in rationalizing the real-time data over the routine state-based sketch of the reaction system.
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Affiliation(s)
- Prasanta Kundu
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
| | - Soma Saha
- Department of Chemistry, Presidency University, 86/1 College Street, Kolkata 700073, India
| | - Gautam Gangopadhyay
- S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700106, India
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9
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Kang J, Park SJ, Kim JH, Chen P, Sung J. Stochastic Kinetics of Nanocatalytic Systems. PHYSICAL REVIEW LETTERS 2021; 126:126001. [PMID: 33834800 DOI: 10.1103/physrevlett.126.126001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 08/18/2020] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
Catalytic reaction events occurring on the surface of a nanoparticle constitute a complex stochastic process. Although advances in modern single-molecule experiments enable direct measurements of individual catalytic turnover events occurring on a segment of a single nanoparticle, we do not yet know how to measure the number of catalytic sites in each segment or how the catalytic turnover counting statistics and the catalytic turnover time distribution are related to the microscopic dynamics of catalytic reactions. Here, we address these issues by presenting a stochastic kinetics for nanoparticle catalytic systems. We propose a new experimental measure of the number of catalytic sites in terms of the mean and variance of the catalytic event count. By considering three types of nanocatalytic systems, we investigate how the mean, the variance, and the distribution of the catalytic turnover time depend on the catalytic reaction dynamics, the heterogeneity of catalytic activity, and communication among catalytic sites. This work enables accurate quantitative analyses of single-molecule experiments for nanocatalytic systems and enzymes with multiple catalytic sites.
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Affiliation(s)
- Jingyu Kang
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
| | - Seong Jun Park
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
| | - Ji-Hyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
| | - Peng Chen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Jaeyoung Sung
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
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10
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Chaudhury S, Singh D, Kolomeisky AB. Theoretical Investigations of the Dynamics of Chemical Reactions on Nanocatalysts with Multiple Active Sites. J Phys Chem Lett 2020; 11:2330-2335. [PMID: 32125856 DOI: 10.1021/acs.jpclett.0c00316] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Recent synthetic advances led to the development of new catalytic particles with well-defined atomic structures and multiple active sites, which are called nanocatalysts. Experimental studies of processes at nanocatalysts uncovered a variety of surprising effects, but the molecular mechanisms of these phenomena remain not well understood. We propose a theoretical method to investigate the dynamics of chemical reactions on catalytic particles with multiple active sites. It is based on a discrete-state stochastic description that allows us to explicitly evaluate dynamic properties of the system. It is found that for independently occurring chemical reactions, the mean turnover times are inversely proportional to the number of active sites, showing no stochastic effects. However, the molecular details of reactions and the number of active sites influence the higher moments of reaction times. Our theoretical method provides a way to quantify the molecular mechanisms of processes at nanocatalysts.
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Affiliation(s)
- Srabanti Chaudhury
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008, India
| | - Divya Singh
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune, Maharashtra 411008, India
| | - Anatoly B Kolomeisky
- Department of Chemistry, Department of Chemical and Biomolecular Engineering, Department of Physics and Astronomy, and Center for Theoretical Biological Physics, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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11
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Song S, Yang GS, Park SJ, Hong S, Kim JH, Sung J. Frequency spectrum of chemical fluctuation: A probe of reaction mechanism and dynamics. PLoS Comput Biol 2019; 15:e1007356. [PMID: 31525182 PMCID: PMC6762214 DOI: 10.1371/journal.pcbi.1007356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 09/26/2019] [Accepted: 08/22/2019] [Indexed: 11/18/2022] Open
Abstract
Even in the steady-state, the number of biomolecules in living cells fluctuates dynamically, and the frequency spectrum of this chemical fluctuation carries valuable information about the dynamics of the reactions creating these biomolecules. Recent advances in single-cell techniques enable direct monitoring of the time-traces of the protein number in each cell; however, it is not yet clear how the stochastic dynamics of these time-traces is related to the reaction mechanism and dynamics. Here, we derive a rigorous relation between the frequency-spectrum of the product number fluctuation and the reaction mechanism and dynamics, starting from a generalized master equation. This relation enables us to analyze the time-traces of the protein number and extract information about dynamics of mRNA number and transcriptional regulation, which cannot be directly observed by current experimental techniques. We demonstrate our frequency spectrum analysis of protein number fluctuation, using the gene network model of luciferase expression under the control of the Bmal 1a promoter in mouse fibroblast cells. We also discuss how the dynamic heterogeneity of transcription and translation rates affects the frequency-spectra of the mRNA and protein number.
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Affiliation(s)
- Sanggeun Song
- Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, Korea
- Department of Chemistry, Chung-Ang University, Seoul, Korea
| | - Gil-Suk Yang
- Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, Korea
- Department of Chemistry, Chung-Ang University, Seoul, Korea
| | - Seong Jun Park
- Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, Korea
- Department of Chemistry, Chung-Ang University, Seoul, Korea
| | - Sungguan Hong
- Department of Chemistry, Chung-Ang University, Seoul, Korea
- * E-mail: (SH); (JHK); (JS)
| | - Ji-Hyun Kim
- Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, Korea
- * E-mail: (SH); (JHK); (JS)
| | - Jaeyoung Sung
- Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, Korea
- Department of Chemistry, Chung-Ang University, Seoul, Korea
- * E-mail: (SH); (JHK); (JS)
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12
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Kang J, Park SJ, Kim J, Sung J. Effects of Non‐Poisson Transcription Dynamics on Mean mRNA Number Dynamics in Living Cells. B KOREAN CHEM SOC 2019. [DOI: 10.1002/bkcs.11827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jingyu Kang
- Creative Research Initiative Center for Chemical Dynamics in Living CellsChung‐Ang University Seoul 06974 South Korea
- Department of ChemistryChung‐Ang University Seoul 06974 South Korea
| | - Seong Jun Park
- Creative Research Initiative Center for Chemical Dynamics in Living CellsChung‐Ang University Seoul 06974 South Korea
- Department of ChemistryChung‐Ang University Seoul 06974 South Korea
| | - Ji‐Hyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living CellsChung‐Ang University Seoul 06974 South Korea
| | - Jaeyoung Sung
- Creative Research Initiative Center for Chemical Dynamics in Living CellsChung‐Ang University Seoul 06974 South Korea
- Department of ChemistryChung‐Ang University Seoul 06974 South Korea
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13
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Shin K, Song S, Song YH, Hahn S, Kim JH, Lee G, Jeong IC, Sung J, Lee KT. Anomalous Dynamics of in Vivo Cargo Delivery by Motor Protein Multiplexes. J Phys Chem Lett 2019; 10:3071-3079. [PMID: 31117686 DOI: 10.1021/acs.jpclett.9b01106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Vesicle transport conducted by motor protein multiplexes (MPMs), which is ubiquitous among eukaryotes, shows anomalous and stochastic dynamics qualitatively different from the dynamics of thermal motion and artificial active matter; the relationship between in vivo vesicle-delivery dynamics and the underlying physicochemical processes is not yet quantitatively understood. Addressing this issue, we perform accurate tracking of individual vesicles, containing upconverting nanoparticles, transported by kinesin-dynein-multiplexes along axonal microtubules. The mean-square-displacement of vesicles along the microtubule exhibits unusual dynamic phase transitions that are seemingly inconsistent with the scaling behavior of the mean-first-passage time over the travel length. These paradoxical results and the vesicle displacement distribution are quantitatively explained and predicted by a multimode MPM model, developed in the current work, where ATP-hydrolysis-coupled motion of MPM has both unidirectional and bidirectional modes.
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Affiliation(s)
- Kyujin Shin
- Department of Chemistry, School of Physics and Chemistry , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
| | - Sanggeun Song
- Creative Research Initiative Center for Chemical Dynamics in Living Cells , Chung-Ang University , Seoul 06974 , Korea
- Department of Chemistry , Chung-Ang University , Seoul 06974 , Korea
- National Institute of Innovative Functional Imaging , Chung-Ang University , Seoul 06974 , Korea
| | - Yo Han Song
- Department of Chemistry, School of Physics and Chemistry , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
| | - Seungsoo Hahn
- Creative Research Initiative Center for Chemical Dynamics in Living Cells , Chung-Ang University , Seoul 06974 , Korea
- Da Vinci College of General Education , Chung-Ang University , Seoul 06974 , Korea
| | - Ji-Hyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living Cells , Chung-Ang University , Seoul 06974 , Korea
| | - Gibok Lee
- Department of Chemistry, School of Physics and Chemistry , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
| | - In-Chun Jeong
- Creative Research Initiative Center for Chemical Dynamics in Living Cells , Chung-Ang University , Seoul 06974 , Korea
- Department of Chemistry , Chung-Ang University , Seoul 06974 , Korea
- National Institute of Innovative Functional Imaging , Chung-Ang University , Seoul 06974 , Korea
| | - Jaeyoung Sung
- Creative Research Initiative Center for Chemical Dynamics in Living Cells , Chung-Ang University , Seoul 06974 , Korea
- Department of Chemistry , Chung-Ang University , Seoul 06974 , Korea
- National Institute of Innovative Functional Imaging , Chung-Ang University , Seoul 06974 , Korea
| | - Kang Taek Lee
- Department of Chemistry, School of Physics and Chemistry , Gwangju Institute of Science and Technology (GIST) , Gwangju 61005 , Korea
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14
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Panigrahy M, Kumar A, Chowdhury S, Dua A. Unraveling mechanisms from waiting time distributions in single-nanoparticle catalysis. J Chem Phys 2019; 150:204119. [DOI: 10.1063/1.5087974] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Manmath Panigrahy
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
| | - Ashutosh Kumar
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
| | - Sutirtha Chowdhury
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
| | - Arti Dua
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
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15
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Park SJ, Song S, Yang GS, Kim PM, Yoon S, Kim JH, Sung J. The Chemical Fluctuation Theorem governing gene expression. Nat Commun 2018; 9:297. [PMID: 29352116 PMCID: PMC5775451 DOI: 10.1038/s41467-017-02737-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 12/20/2017] [Indexed: 11/20/2022] Open
Abstract
Gene expression is a complex stochastic process composed of numerous enzymatic reactions with rates coupled to hidden cell-state variables. Despite advances in single-cell technologies, the lack of a theory accurately describing the gene expression process has restricted a robust, quantitative understanding of gene expression variability among cells. Here we present the Chemical Fluctuation Theorem (CFT), providing an accurate relationship between the environment-coupled chemical dynamics of gene expression and gene expression variability. Combined with a general, accurate model of environment-coupled transcription processes, the CFT provides a unified explanation of mRNA variability for various experimental systems. From this analysis, we construct a quantitative model of transcription dynamics enabling analytic predictions for the dependence of mRNA noise on the mRNA lifetime distribution, confirmed against stochastic simulation. This work suggests promising new directions for quantitative investigation into cellular control over biological functions by making complex dynamics of intracellular reactions accessible to rigorous mathematical deductions. A unified framework to understand gene expression noise is still lacking. Here the authors derive a universal theorem relating the biological noise with dynamics of birth and death processes and present a model of transcription dynamics, allowing analytical prediction of the dependence of mRNA noise on mRNA lifetime variability.
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Affiliation(s)
- Seong Jun Park
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, 06974, Korea.,Department of Chemistry, Chung-Ang University, Seoul, 06974, Korea.,National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul, 06974, Korea
| | - Sanggeun Song
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, 06974, Korea.,Department of Chemistry, Chung-Ang University, Seoul, 06974, Korea.,National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul, 06974, Korea
| | - Gil-Suk Yang
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, 06974, Korea
| | - Philip M Kim
- Terrence Donnelly Center for Cellular and Biomolecular Research, Department of Molecular Genetics and Department of Computer Science, University of Toronto, Toronto, M5S 3E1, ON, Canada
| | - Sangwoon Yoon
- Department of Chemistry, Chung-Ang University, Seoul, 06974, Korea.
| | - Ji-Hyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, 06974, Korea.
| | - Jaeyoung Sung
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul, 06974, Korea. .,Department of Chemistry, Chung-Ang University, Seoul, 06974, Korea. .,National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul, 06974, Korea.
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16
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Jeong IC, Song S, Kim D, Park SJ, Kim JH, Sung J. Comment on "Nonrenewal Statistics in the Catalytic Activity of Enzyme Molecules at Mesoscopic Concentrations". PHYSICAL REVIEW LETTERS 2017; 119:099801. [PMID: 28949572 DOI: 10.1103/physrevlett.119.099801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Indexed: 06/07/2023]
Affiliation(s)
- In-Chun Jeong
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 06974, Korea
| | - Sanggeun Song
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 06974, Korea
| | - Daehyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 06974, Korea
| | - Seong Jun Park
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 06974, Korea
| | - Ji-Hyun Kim
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
| | - Jaeyoung Sung
- Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University, Seoul 06974, Korea
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17
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Avila TR, Piephoff DE, Cao J. Generic Schemes for Single-Molecule Kinetics. 2: Information Content of the Poisson Indicator. J Phys Chem B 2017; 121:7750-7760. [DOI: 10.1021/acs.jpcb.7b01516] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Thomas R. Avila
- Department
of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - D. Evan Piephoff
- Department
of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jianshu Cao
- Department
of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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18
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Park SJ, Song S, Jeong IC, Koh HR, Kim JH, Sung J. Nonclassical Kinetics of Clonal yet Heterogeneous Enzymes. J Phys Chem Lett 2017; 8:3152-3158. [PMID: 28609615 DOI: 10.1021/acs.jpclett.7b01218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Enzyme-to-enzyme variation in the catalytic rate is ubiquitous among single enzymes created from the same genetic information, which persists over the lifetimes of living cells. Despite advances in single-enzyme technologies, the lack of an enzyme reaction model accounting for the heterogeneous activity of single enzymes has hindered a quantitative understanding of the nonclassical stochastic outcome of single enzyme systems. Here we present a new statistical kinetics and exactly solvable models for clonal yet heterogeneous enzymes with possibly nonergodic state dynamics and state-dependent reactivity, which enable a quantitative understanding of modern single-enzyme experimental results for the mean and fluctuation in the number of product molecules created by single enzymes. We also propose a new experimental measure of the heterogeneity and nonergodicity for a system of enzymes.
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Affiliation(s)
- Seong Jun Park
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University , Seoul 06974, Korea
| | - Sanggeun Song
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University , Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University , Seoul 06974, Korea
| | - In-Chun Jeong
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University , Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University , Seoul 06974, Korea
| | - Hye Ran Koh
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University , Seoul 06974, Korea
| | - Ji-Hyun Kim
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
| | - Jaeyoung Sung
- National Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University , Seoul 06974, Korea
- Department of Chemistry, Chung-Ang University , Seoul 06974, Korea
- National Institute of Innovative Functional Imaging, Chung-Ang University , Seoul 06974, Korea
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19
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Berg MA, Darvin JR. Measuring a hidden coordinate: Rate-exchange kinetics from 3D correlation functions. J Chem Phys 2016; 145:054119. [DOI: 10.1063/1.4960186] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Mark A. Berg
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Jason R. Darvin
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
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20
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Reuveni S. Optimal Stochastic Restart Renders Fluctuations in First Passage Times Universal. PHYSICAL REVIEW LETTERS 2016; 116:170601. [PMID: 27176510 DOI: 10.1103/physrevlett.116.170601] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Indexed: 05/27/2023]
Abstract
Stochastic restart may drastically reduce the expected run time of a computer algorithm, expedite the completion of a complex search process, or increase the turnover rate of an enzymatic reaction. These diverse first-passage-time (FPT) processes seem to have very little in common but it is actually quite the other way around. Here we show that the relative standard deviation associated with the FPT of an optimally restarted process, i.e., one that is restarted at a constant (nonzero) rate which brings the mean FPT to a minimum, is always unity. We interpret, further generalize, and discuss this finding and the implications arising from it.
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Affiliation(s)
- Shlomi Reuveni
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, Massachusetts 02115, USA
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21
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Rotbart T, Reuveni S, Urbakh M. Michaelis-Menten reaction scheme as a unified approach towards the optimal restart problem. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:060101. [PMID: 26764608 DOI: 10.1103/physreve.92.060101] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Indexed: 05/27/2023]
Abstract
We study the effect of restart, and retry, on the mean completion time of a generic process. The need to do so arises in various branches of the sciences and we show that it can naturally be addressed by taking advantage of the classical reaction scheme of Michaelis and Menten. Stopping a process in its midst-only to start it all over again-may prolong, leave unchanged, or even shorten the time taken for its completion. Here we are interested in the optimal restart problem, i.e., in finding a restart rate which brings the mean completion time of a process to a minimum. We derive the governing equation for this problem and show that it is exactly solvable in cases of particular interest. We then continue to discover regimes at which solutions to the problem take on universal, details independent forms which further give rise to optimal scaling laws. The formalism we develop, and the results obtained, can be utilized when optimizing stochastic search processes and randomized computer algorithms. An immediate connection with kinetic proofreading is also noted and discussed.
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Affiliation(s)
- Tal Rotbart
- School of Chemistry, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Shlomi Reuveni
- Department of Systems Biology, Harvard Medical School, 200 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Michael Urbakh
- School of Chemistry, Tel-Aviv University, Tel-Aviv 69978, Israel
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22
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Modeling the heterogeneous catalytic activity of a single nanoparticle using a first passage time distribution formalism. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.10.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Kumar A, Maity H, Dua A. Parallel versus Off-Pathway Michaelis–Menten Mechanism for Single-Enzyme Kinetics of a Fluctuating Enzyme. J Phys Chem B 2015; 119:8490-500. [DOI: 10.1021/acs.jpcb.5b03752] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ashutosh Kumar
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
| | - Hiranmay Maity
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
| | - Arti Dua
- Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India
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24
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Chaudhury S. Poisson Indicator and Fano Factor for Probing Dynamic Disorder in Single-Molecule Enzyme Inhibition Kinetics. J Phys Chem B 2014; 118:10405-12. [DOI: 10.1021/jp506141v] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Srabanti Chaudhury
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, Maharashtra, India
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25
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Abstract
The Michaelis-Menten equation provides a hundred-year-old prediction by which any increase in the rate of substrate unbinding will decrease the rate of enzymatic turnover. Surprisingly, this prediction was never tested experimentally nor was it scrutinized using modern theoretical tools. Here we show that unbinding may also speed up enzymatic turnover--turning a spotlight to the fact that its actual role in enzymatic catalysis remains to be determined experimentally. Analytically constructing the unbinding phase space, we identify four distinct categories of unbinding: inhibitory, excitatory, superexcitatory, and restorative. A transition in which the effect of unbinding changes from inhibitory to excitatory as substrate concentrations increase, and an overlooked tradeoff between the speed and efficiency of enzymatic reactions, are naturally unveiled as a result. The theory presented herein motivates, and allows the interpretation of, groundbreaking experiments in which existing single-molecule manipulation techniques will be adapted for the purpose of measuring enzymatic turnover under a controlled variation of unbinding rates. As we hereby show, these experiments will not only shed first light on the role of unbinding but will also allow one to determine the time distribution required for the completion of the catalytic step in isolation from the rest of the enzymatic turnover cycle.
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26
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Chowdhury D. Michaelis-Menten at 100 and allosterism at 50: driving molecular motors in a hailstorm with noisy ATPase engines and allosteric transmission. FEBS J 2013; 281:601-11. [DOI: 10.1111/febs.12596] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 10/25/2013] [Accepted: 10/28/2013] [Indexed: 11/29/2022]
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27
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Moffitt JR, Bustamante C. Extracting signal from noise: kinetic mechanisms from a Michaelis-Menten-like expression for enzymatic fluctuations. FEBS J 2013; 281:498-517. [PMID: 24428386 DOI: 10.1111/febs.12545] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/17/2013] [Accepted: 09/23/2013] [Indexed: 12/25/2022]
Abstract
Enzyme-catalyzed reactions are naturally stochastic, and precision measurements of these fluctuations, made possible by single-molecule methods, promise to provide fundamentally new constraints on the possible mechanisms underlying these reactions. We review some aspects of statistical kinetics: a new field with the goal of extracting mechanistic information from statistical measures of fluctuations in chemical reactions. We focus on a widespread and important statistical measure known as the randomness parameter. This parameter is remarkably simple in that it is the squared coefficient of variation of the cycle completion times, although it places significant limits on the minimal complexity of possible enzymatic mechanisms. Recently, a general expression has been introduced for the substrate dependence of the randomness parameter that is for rate fluctuations what the Michaelis-Menten expression is for the mean rate of product generation. We discuss the information provided by the new kinetic parameters introduced by this expression and demonstrate that this expression can simplify the vast majority of published models.
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Affiliation(s)
- Jeffrey R Moffitt
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
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28
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Horowitz JM, Sagawa T, Parrondo JMR. Imitating chemical motors with optimal information motors. PHYSICAL REVIEW LETTERS 2013; 111:010602. [PMID: 23862988 DOI: 10.1103/physrevlett.111.010602] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Indexed: 06/02/2023]
Abstract
To induce transport, detailed balance must be broken. A common mechanism is to bias the dynamics with a thermodynamic fuel, such as chemical energy. An intriguing, alternative strategy is for a Maxwell demon to effect the bias using feedback. We demonstrate that these two different mechanisms lead to distinct thermodynamics by contrasting a chemical motor and information motor with identical dynamics. To clarify this difference, we study both models within one unified framework, highlighting the role of the interaction between the demon and the motor. This analysis elucidates the manner in which information is incorporated into a physical system.
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Affiliation(s)
- Jordan M Horowitz
- Departamento de Física Atómica, Molecular y Nuclear and GISC, Universidad Complutense de Madrid, 28040 Madrid, Spain
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29
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Bassingthwaighte JB, Chinn TM. Reexamining Michaelis-Menten enzyme kinetics for xanthine oxidase. ADVANCES IN PHYSIOLOGY EDUCATION 2013; 37:37-48. [PMID: 23471247 PMCID: PMC3776473 DOI: 10.1152/advan.00107.2012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 11/26/2012] [Indexed: 06/01/2023]
Abstract
Abbreviated expressions for enzyme kinetic expressions, such as the Michaelis-Menten (M-M) equations, are based on the premise that enzyme concentrations are low compared with those of the substrate and product. When one does progress experiments, where the solute is consumed during conversion to form a series of products, the idealized conditions are violated. Here, we analyzed data of xanthine oxidase in vitro from Escribano et al. (Biochem J 254: 829, 1988) on two conversions in series, hypoxanthine to xanthine to uric acid. Analyses were done using four models: standard irreversible M-M reactions (model 1), Escribano et al.'s M-M forward reaction expressions with product inhibition (model 2), fully reversible M-M equations (model 3), and standard differential equations allowing forward and backward reactions with mass balance accounting for binding (model 4). The results showed that the need for invoking product inhibition vanishes with more complete analyses. The reactions were not quite irreversible, so the backward reaction had a small effect. Even though the enzyme concentration was only 1-2% of the initial substrate concentrations, accounting for the fraction of solutes bound to the enzyme did influence the parameter estimates, but in this case, the M-M model overestimated Michaelis constant values by only about one-third. This article also presents the research and models in a reproducible and publicly available form.
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30
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Lim YR, Park SJ, Lee SY, Sung JY. Nonclassical Chemical Kinetics for Description of Chemical Fluctuation in a Dynamically Heterogeneous Biological System. B KOREAN CHEM SOC 2012. [DOI: 10.5012/bkcs.2012.33.3.963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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31
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Lim YR, Park SJ, Park BJ, Cao J, Silbey RJ, Sung J. Reaction Event Counting Statistics of Biopolymer Reaction Systems with Dynamic Heterogeneity. J Chem Theory Comput 2012; 8:1415-25. [DOI: 10.1021/ct200785q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yu Rim Lim
- Department of Chemistry, Chung-Ang
University, Seoul 156-756, Korea
| | - Seong Jun Park
- Department of Chemistry, Chung-Ang
University, Seoul 156-756, Korea
| | - Bo Jung Park
- Department of Chemistry, Chung-Ang
University, Seoul 156-756, Korea
| | - Jianshu Cao
- Department of Chemistry, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Robert J. Silbey
- Department of Chemistry, Massachusetts
Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jaeyoung Sung
- Department of Chemistry, Chung-Ang
University, Seoul 156-756, Korea
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