1
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Rao YF, Sun LZ, Luo MB. Na +-Mg 2+ ion effects on conformation and translocation dynamics of single-stranded RNA: Cooperation and competition. Int J Biol Macromol 2024; 267:131273. [PMID: 38569994 DOI: 10.1016/j.ijbiomac.2024.131273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 03/20/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024]
Abstract
The nanopore-based translocation of a single-stranded RNA (ssRNA) in mixed salt solution has garnered increasing interest for its biological and technological significance. However, it is challenging to comprehensively understand the effects of the mixed ion species on the translocation dynamics due to their cooperation and competition, which can be directly reflected by the ion screening and neutralizing effects, respectively. In this study, Langevin dynamics simulation is employed to investigate the properties of ssRNA conformation and translocation in mixed Na+-Mg2+ ion environments. Simulation results reveal that the ion screening effect dominates the change in the ssRNA conformational size, the ion neutralizing effect controls the capture rate of the ssRNA by the nanopore, and both of them take charge of the different changes in translocation time of the ssRNA under various mixed ion environments. Under high Na+ ion concentration, as Mg2+ concentration increases, the ion neutralizing effect strengthens, weakening the driving force inside the nanopore, leading to longer translocation time. Conversely, at low Na+ concentration, an increase in Mg2+ concentration enhances the ion screening effect, aiding in faster translocation. Furthermore, these simulation results will be explained by quantitative analysis, advancing a deeper understanding of the complicated effects of the mixed Na+-Mg2+ ions.
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Affiliation(s)
- Yi-Fan Rao
- School of Physics, Zhejiang University, Hangzhou 310027, China; Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China
| | - Li-Zhen Sun
- Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China.
| | - Meng-Bo Luo
- School of Physics, Zhejiang University, Hangzhou 310027, China.
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2
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Upadhyay G, Kapri R, Chaudhuri A. Homopolymer and heteropolymer translocation through patterned pores under fluctuating forces. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2024; 47:23. [PMID: 38573533 DOI: 10.1140/epje/s10189-024-00417-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Accepted: 03/18/2024] [Indexed: 04/05/2024]
Abstract
We investigate the translocation of a semiflexible polymer through extended patterned pores using Langevin dynamics simulations, specifically focusing on the influence of a time-dependent driving force. Our findings reveal that, akin to its flexible counterpart, a rigid chain-like molecule translocates faster when subjected to an oscillating force than a constant force of equivalent average magnitude. The enhanced translocation is strongly correlated with the stiffness of the polymer and the stickiness of the pores. The arrangement of the pores plays a pivotal role in translocation dynamics, deeply influenced by the interplay between polymer stiffness and pore-polymer interactions. For heterogeneous polymers with periodically varying stiffness, the oscillating force introduces significant variations in the translocation time distributions based on segment sizes and orientations. On the basis of these insights, we propose a sequencing approach that harnesses distinct pore surface properties that are capable of accurately predicting sequences in heteropolymers with diverse bending rigidities.
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Affiliation(s)
- Gokul Upadhyay
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, 140306, India
| | - Rajeev Kapri
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, 140306, India
| | - Abhishek Chaudhuri
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli, 140306, India.
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3
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Upadhyay G, Kapri R, Chaudhuri A. Gain reversal in the translocation dynamics of a semiflexible polymer through a flickering pore. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:185101. [PMID: 38262064 DOI: 10.1088/1361-648x/ad21a9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 01/23/2024] [Indexed: 01/25/2024]
Abstract
We study the driven translocation of a semiflexible polymer through an attractive extended pore with a periodically oscillating width. Similar to its flexible counterpart, a stiff polymer translocates through an oscillating pore more quickly than a static pore whose width is equal to the oscillating pore's mean width. This efficiency quantified as a gain in the translocation time, highlights a considerable dependence of the translocation dynamics on the stiffness of the polymer and the attractive nature of the pore. The gain characteristics for various polymer stiffness exhibit a trend reversal when the stickiness of the pore is changed. The gain reduces with increasing stiffness for a lower attractive strength of the pore, whereas it increases with increasing stiffness for higher attractive strengths. Such a dependence leads to the possibility of a high degree of robust selectivity in the translocation process.
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Affiliation(s)
- Gokul Upadhyay
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli 140306, India
| | - Rajeev Kapri
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli 140306, India
| | - Abhishek Chaudhuri
- Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, Knowledge City, S. A. S. Nagar, Manauli 140306, India
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4
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Tan F, Wang J, Yan R, Zhao N. Forced and spontaneous translocation dynamics of a semiflexible active polymer in two dimensions. SOFT MATTER 2024; 20:1120-1132. [PMID: 38224190 DOI: 10.1039/d3sm01409f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Polymer translocation is a fundamental topic in non-equilibrium physics and is crucially important to many biological processes in life. In the present work, we adopt two-dimensional Langevin dynamics simulations to study the forced and spontaneous translocation dynamics of an active filament. The influence of polymer stiffness on the underlying dynamics is explicitly analyzed. For the forced translocation, the results show a robust stiffness-induced inhibition, and the translocation time exhibits a dual-exponent scaling relationship with the bending modulus. Tension propagation (TP) is also examined, where we find prominent modifications in terms of both activity and stiffness. For spontaneous translocation into a pure solvent, the translocation time is almost independent of the polymer stiffness. However, when the polymer is translocated into a porous medium, an intriguing non-monotonic alteration of translocation time with increasing chain stiffness is demonstrated. The semiflexible chain is beneficial for translocation while the rigid chain is not conducive. Stiffness regulation on the diffusion dynamics of the polymer in porous media shows a consistent scenario. The interplay of activity, stiffness, and porous crowding provides a new mechanism for understanding the non-trivial translocation dynamics of an active filament in complex environments.
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Affiliation(s)
- Fei Tan
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Jingli Wang
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Ran Yan
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Nanrong Zhao
- College of Chemistry, Sichuan University, Chengdu 610064, China.
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5
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Hanafy MS, Cui Z. Connexin-Containing Vesicles for Drug Delivery. AAPS J 2024; 26:20. [PMID: 38267725 DOI: 10.1208/s12248-024-00889-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 12/20/2023] [Indexed: 01/26/2024] Open
Abstract
Connexin is a transmembrane protein present on the cell membrane of most cell types. Connexins assemble into a hexameric hemichannel known as connexon that pairs with another hemichannel present on a neighboring cell to form gap junction that acts as a channel or pore for the transport of ions and small molecules between the cytoplasm of the two cells. Extracellular vesicles released from connexin-expressing cells could carry connexin hemichannels on their surface and couple with another connexin hemichannel on a distant recipient cell to allow the transfer of the intravesicular content directly into the cytoplasm. Connexin-containing vesicles can be potentially utilized for intracellular drug delivery. In this review, we introduced cell-derived, connexin-containing extracellular vesicles and cell-free connexin-containing liposomes, methods of preparing them, procedures to load cargos in them, factors regulating the connexin hemichannel activity, (potential) applications of connexin-containing vesicles in drug delivery, and finally the challenges and future directions in realizing the promises of this platform delivery system for (intracellular) drug delivery.
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Affiliation(s)
- Mahmoud S Hanafy
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, Texas, USA
| | - Zhengrong Cui
- Division of Molecular Pharmaceutics and Drug Delivery, College of Pharmacy, The University of Texas at Austin, Austin, Texas, USA.
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6
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Tan F, Yan R, Zhao C, Zhao N. Translocation Dynamics of an Active Filament through a Long-Length Scale Channel. J Phys Chem B 2023; 127:8603-8615. [PMID: 37782905 DOI: 10.1021/acs.jpcb.3c04250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Active filament translocation through a confined space is crucial for diverse biological processes. By using Langevin dynamics simulations, we investigate the translocation dynamics of an axially self-propelled chain through a channel. First, results show a suggestive reciprocal scaling of translocation time versus active force. Second, in the case of a long channel, we demonstrate a very intriguing nonmonotonic change of translocation time with increasing channel width. The driving force shows a similar trend, providing a consistent picture to understand the unexpected channel width effect. In particular, in a moderately broad channel, the disordered chain conformation results in a loss of driving force and thus inhibits translocation dynamics. Chain adsorption might occur in a wide channel, which accounts for a facilitated translocation. Lastly, we connect the translocation process to tension propagation (TP). A modified TP picture is proposed to interpret the waiting time distribution. Our work highlights the new phenomenology owing to the crucial interplay of activity and spacial confinement, which drives the translocation dynamics, going beyond the traditional entropic barrier scenario.
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Affiliation(s)
- Fei Tan
- College of Chemistry, Sichuan University, Chengdu 610065, China
| | - Ran Yan
- College of Chemistry, Sichuan University, Chengdu 610065, China
| | - Chaonan Zhao
- College of Chemistry, Sichuan University, Chengdu 610065, China
| | - Nanrong Zhao
- College of Chemistry, Sichuan University, Chengdu 610065, China
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7
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Singh SL, Chauhan K, Bharadwaj AS, Kishore V, Laux P, Luch A, Singh AV. Polymer Translocation and Nanopore Sequencing: A Review of Advances and Challenges. Int J Mol Sci 2023; 24:6153. [PMID: 37047125 PMCID: PMC10094227 DOI: 10.3390/ijms24076153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/01/2023] [Accepted: 02/28/2023] [Indexed: 03/31/2023] Open
Abstract
Various biological processes involve the translocation of macromolecules across nanopores; these pores are basically protein channels embedded in membranes. Understanding the mechanism of translocation is crucial to a range of technological applications, including DNA sequencing, single molecule detection, and controlled drug delivery. In this spirit, numerous efforts have been made to develop polymer translocation-based sequencing devices, these efforts include findings and insights from theoretical modeling, simulations, and experimental studies. As much as the past and ongoing studies have added to the knowledge, the practical realization of low-cost, high-throughput sequencing devices, however, has still not been realized. There are challenges, the foremost of which is controlling the speed of translocation at the single monomer level, which remain to be addressed in order to use polymer translocation-based methods for sensing applications. In this article, we review the recent studies aimed at developing control over the dynamics of polymer translocation through nanopores.
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Affiliation(s)
- Swarn Lata Singh
- Department of Physics, Mahila Mahavidyalaya (MMV), Banaras Hindu University, Varanasi 221005, UP, India
| | - Keerti Chauhan
- Department of Physics, Banaras Hindu University, Varanasi 221005, UP, India
| | - Atul S. Bharadwaj
- Department of Physics, CMP Degree College, University of Allahabad, Prayagraj 211002, UP, India
| | - Vimal Kishore
- Department of Physics, Banaras Hindu University, Varanasi 221005, UP, India
| | - Peter Laux
- Department of Chemical and Product Safety, German Federal Institute of Risk Assessment (BfR) Maxdohrnstrasse 8-10, 10589 Berlin, Germany
| | - Andreas Luch
- Department of Chemical and Product Safety, German Federal Institute of Risk Assessment (BfR) Maxdohrnstrasse 8-10, 10589 Berlin, Germany
| | - Ajay Vikram Singh
- Department of Chemical and Product Safety, German Federal Institute of Risk Assessment (BfR) Maxdohrnstrasse 8-10, 10589 Berlin, Germany
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8
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Sharma A, Kapri R, Chaudhuri A. Driven translocation of a semiflexible polymer through a conical channel in the presence of attractive surface interactions. Sci Rep 2022; 12:19081. [PMID: 36351960 PMCID: PMC9646819 DOI: 10.1038/s41598-022-21845-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 10/04/2022] [Indexed: 11/11/2022] Open
Abstract
We study the translocation of a semiflexible polymer through a conical channel with attractive surface interactions and a driving force which varies spatially inside the channel. Using the results of the translocation dynamics of a flexible polymer through an extended channel as control, we first show that the asymmetric shape of the channel gives rise to non-monotonic features in the total translocation time as a function of the apex angle of the channel. The waiting time distributions of individual monomer beads inside the channel show unique features strongly dependent on the driving force and the surface interactions. Polymer stiffness results in longer translocation times for all angles of the channel. Further, non-monotonic features in the translocation time as a function of the channel angle changes substantially as the polymer becomes stiffer, which is reflected in the changing features of the waiting time distributions. We construct a free energy description of the system incorporating entropic and energetic contributions in the low force regime to explain the simulation results.
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Affiliation(s)
- Andri Sharma
- grid.458435.b0000 0004 0406 1521Department of Physical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S. A. S. Nagar, Mohali, 140306 Punjab India
| | - Rajeev Kapri
- grid.458435.b0000 0004 0406 1521Department of Physical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S. A. S. Nagar, Mohali, 140306 Punjab India
| | - Abhishek Chaudhuri
- grid.458435.b0000 0004 0406 1521Department of Physical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S. A. S. Nagar, Mohali, 140306 Punjab India
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9
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Li K, Oiwa NN, Mishra SK, Heermann DW. Inter-nucleosomal potentials from nucleosomal positioning data. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:33. [PMID: 35403917 PMCID: PMC9001623 DOI: 10.1140/epje/s10189-022-00185-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
No systematic method exists to derive inter-nucleosomal potentials between nucleosomes along a chromosome consistently across a given genome. Such potentials can yield information on nucleosomal ordering, thermal as well as mechanical properties of chromosomes. Thus, indirectly, they shed light on a possible mechanical genomic code along a chromosome. To develop a method yielding effective inter-nucleosomal potentials between nucleosomes, a generalized Lennard-Jones potential for the parameterization is developed based on nucleosomal positioning data. This approach eliminates some of the problems that the underlying nucleosomal positioning data have, rendering the extraction difficult on the individual nucleosomal level. Furthermore, patterns on which to base a classification along a chromosome appear on larger domains, such as hetero- and euchromatin. An intuitive selection strategy for the noisy optimization problem is employed to derive effective exponents for the generalized potential. The method is tested on the Candida albicans genome. Applying k-means clustering based on potential parameters and thermodynamic compressibilities, a genome-wide clustering of nucleosome sequences is obtained for C. albicans. This clustering shows that a chromosome beyond the classical dichotomic categories of hetero- and euchromatin is more feature-rich.
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Affiliation(s)
- Kunhe Li
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, D-69120, Heidelberg, Germany
| | - Nestor Norio Oiwa
- Department of Basic Science, Universidade Federal Fluminense, Rua Doutor Sílvio Henrique Braune 22, Centro, Nova Friburgo, 28625-650, Brazil
| | - Sujeet Kumar Mishra
- Center for Computational Biology and Bioinformatics, School of Computational and Integrative Sciences (SCIS) Jawaharlal Nehru University, New Delhi, India
| | - Dieter W Heermann
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, D-69120, Heidelberg, Germany.
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10
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Trementozzi AN, Zhao C, Smyth H, Cui Z, Stachowiak JC. Gap Junction-Mediated Delivery of Polymeric Macromolecules. ACS Biomater Sci Eng 2022; 8:1566-1572. [PMID: 35263989 PMCID: PMC9157716 DOI: 10.1021/acsbiomaterials.1c01459] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cellular delivery of therapeutic macromolecules such as proteins, peptides, and nucleic acids remains limited due to inefficient transport across the cellular plasma membrane. Gap junction channels, composed of connexin proteins, provide a mechanism for direct transfer of small molecules across membranes, and recent evidence suggests that the transfer of larger, polymer-like molecules such as microRNAs may be possible. Here, we report direct evidence of gap junction-mediated transfer of polymeric macromolecules. Specifically, we examined the transport of dextran chains with molecular weights ranging from 10 to 70 kDa. We found that dextran chains of up to 40 kDa can diffuse through at least five cell layers in a gap junction-dependent manner within a 30 min time frame. Further, we evaluated the ability of connectosomes, cell-derived vesicles containing functional connexin proteins, to be loaded with dextran chains. By opening connexon hemichannel pores within the membranes of connectosomes, we found that 10 kDa dextran was loaded into more than 90% of vesicles, with reduced levels of loading for dextran chains of larger molecular weight. Upon delivering 10 kDa dextran-loaded connectosomes to cells, we further found that connectosomes transferred these membrane-impermeable molecules to the cellular cytosol with dramatically improved efficiency in comparison to the delivery of free, unencapsulated dextran. Collectively, these results reveal that polymeric macromolecules can be delivered to cells via gap junctions, suggesting that the gap junction route may be useful for the delivery of polymeric therapeutic molecules, such as nucleic acids and peptides.
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Affiliation(s)
- Andrea N Trementozzi
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Chi Zhao
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Hugh Smyth
- College of Pharmacy, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Zhengrong Cui
- College of Pharmacy, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Jeanne C Stachowiak
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
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11
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Translocation, Rejection and Trapping of Polyampholytes. Polymers (Basel) 2022; 14:polym14040797. [PMID: 35215709 PMCID: PMC8877523 DOI: 10.3390/polym14040797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/11/2022] [Accepted: 02/13/2022] [Indexed: 12/04/2022] Open
Abstract
Polyampholytes (PA) are a special class of polymers comprising both positive and negative monomers along their sequence. Most proteins have positive and negative residues and are PAs. Proteins have a well-defined sequence while synthetic PAs have a random charge sequence. We investigated the translocation behavior of random polyampholyte chains through a pore under the action of an electric field by means of Monte Carlo simulations. The simulations incorporated a realistic translocation potential profile along an extended asymmetric pore and translocation was studied for both directions of engagement. The study was conducted from the perspective of statistics for disordered systems. The translocation behavior (translocation vs. rejection) was recorded for all 220 sequences comprised of N = 20 charged monomers. The results were compared with those for 107 random sequences of N = 40 to better demonstrate asymptotic laws. At early times, rejection was mainly controlled by the charge sequence of the head part, but late translocation/rejection was governed by the escape from a trapped state over an antagonistic barrier built up along the sequence. The probability distribution of translocation times from all successful attempts revealed a power-law tail. At finite times, there was a population of trapped sequences that relaxed very slowly (logarithmically) with time. If a subensemble of sequences with prescribed net charge was considered the power-law decay was steeper for a more favorable net charge. Our findings were rationalized by theoretical arguments developed for long chains. We also provided operational criteria for the translocation behavior of a sequence, explaining the selection by the translocation process. From the perspective of protein translocation, our findings can help rationalize the behavior of intrinsically disordered proteins (IDPs), which can be modeled as polyampholytes. Most IDP sequences have a strong net charge favoring translocation. Even for sequences with those large net charges, the translocation times remained very dispersed and the translocation was highly sequence-selective.
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12
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Chen X, Chen J, Zhuo BY, Yang X, Luo MB. Simulation study for the pulling translocation of a polymer globule. Polym J 2021. [DOI: 10.1038/s41428-021-00502-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Haji Abdolvahab R, Niknam Hamidabad M. Pore shapes effects on polymer translocation. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2020; 43:76. [PMID: 33306147 DOI: 10.1140/epje/i2020-12001-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/12/2020] [Indexed: 06/12/2023]
Abstract
We translocated polymers through pores of different shapes and interaction patterns in three dimensions by Langevin molecular dynamics. There were four simple cylindrical pores of the same length but with different diameters. The results showed that even though decreasing the pore diameter would always decrease the translocation velocity, it was strongly dependent on the shape of the increased pore diameter. Although increasing the pore diameter made the translocation faster in simple cylindrical pores, it was complicated in different pore shapes, e.g. increasing the diameter in the middle decreased the translocation velocity. Investigating polymer shapes through the translocation process and comparing the shapes by the cumulative waiting time for different pore structures reveals the non-equilibrium properties of translocation. Moreover, polymer shape parameters such as gyration radius, polymer center of mass, and average aspect ratio help us to distinguish different pore shapes and/or different polymers.
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14
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Niknam Hamidabad M, Asgari S, Haji Abdolvahab R. Nanoparticle-assisted polymer translocation through a nanopore. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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15
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Nagarajan K, Chen SB. Polyelectrolyte Translocation through a Corrugated Nanopore. MACROMOL THEOR SIMUL 2020. [DOI: 10.1002/mats.202000042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Karthik Nagarajan
- Department of Chemical & Biomolecular EngineeringNational University of Singapore Singapore 117585 Singapore
| | - Shing Bor Chen
- Department of Chemical & Biomolecular EngineeringNational University of Singapore Singapore 117585 Singapore
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16
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Singh S. Dynamics of the mixtures of fullerene‐60 and aromatic solvents: A molecular dynamics approach. J PHYS ORG CHEM 2020. [DOI: 10.1002/poc.4103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Satnam Singh
- Department of Physical Sciences Indian Institute of Science Education & Research (IISER) Mohali Sector 81 SAS Nagar, Manauli Punjab 140306 India
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17
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Yu WC. Translocation of Heterogeneous Flexible Polymers Assisted by Binding Particles. CHINESE JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1007/s10118-020-2387-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Wang C, Zhou YL, Sun LZ, Chen YC, Luo MB. Simulation study on the migration of diblock copolymers in periodically patterned slits. J Chem Phys 2019; 150:164904. [PMID: 31042899 DOI: 10.1063/1.5093791] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The forced migration of diblock copolymers (ANABNB) in periodically patterned slits was investigated by using Langevin dynamics simulation. The lower surface of the slit consists of stripe α and stripe β distributed in alternating sequence, while the upper one is formed only by stripe β. The interaction between block A and stripe α is strongly attractive, while all other interactions are purely repulsive. Simulation results show that the migration of the diblock copolymer is remarkably dependent on the driving force and there is a transition region at moderate driving force. The transition driving force ft, where the transition region occurs, decreases monotonously with increasing length of block B (NB) but is independent of the polymer length and the periodic length of the slit, which is interpreted from the free energy landscape of diblock copolymer migration. The results also show that periodic slits could be used to separate diblock polymers with different NB by tuning the external driving force.
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Affiliation(s)
- Chao Wang
- Department of Physics, Taizhou University, Taizhou 318000, China
| | - Yan-Li Zhou
- Department of Physics, Taizhou University, Taizhou 318000, China
| | - Li-Zhen Sun
- Department of Applied Physics, Zhejiang University of Technology, Hangzhou 310023, China
| | - Ying-Cai Chen
- Department of Physics, Taizhou University, Taizhou 318000, China
| | - Meng-Bo Luo
- Department of Physics, Zhejiang University, Hangzhou 310027, China
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