{"title":"How a mixture of microRNA-29a (miR-29a) and microRNA-144 (miR-144) cancer biomarkers interacts with a graphene quantum dot","authors":"Darunee Traiphothon , Tadsanee Awang , Nattapon Kuntip , Deanpen Japrung , Prapasiri Pongprayoon","doi":"10.1016/j.jmgm.2024.108881","DOIUrl":"10.1016/j.jmgm.2024.108881","url":null,"abstract":"<div><div>MicroRNAs (miRNAs) which are small non-coding RNAs have been reported to be potential cancer biomarker. However, it is difficult to extract such short RNA from a sample matrix. New effective strategies are required. Recently, graphene quantum dots (GQDs) have been used to detect nucleotides in many biosensor platforms, but their applications for miRNA extraction remain limited. GQD was reported to be able to collect short miRNA, but its performance to collect miRNAs with different structure remains unknown. Thus, in this work, the capability of GQD to interact with two different miRNAs is investigated. A mixture of hairpin-like miR-29a and circular miR-144 molecules are used as a representative of two miRNA morphologies. Two systems (a miRNA mixture, comprising 4 of miR-29a and 4 of miR-144, with (miR_GQD) and without GQD (miR)) were studied in comparison. MiRNAs in a mixture (miR) can aggregate, but no permanent miRNA assembly is captured. In contrast, the presence of GQD can rapidly and spontaneously activate the permanent miRNA/GQD clustering. This finding highlights the ability of GQD to be a miRNA collector. Interestingly, all GQD-bound miRNAs do not unfold. This allows the easy accessibility for probes. Also, nano-sized GQD seems to prefer hairpin miR-29a. The free 5’ terminus of miR-29a acts as the sticky end to adhere on GQD. This work highlights the importance of RNA secondary structure on GQD/miRNA aggregation capability. An insight obtained here will be useful for further design of miRNA isolation strategies.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"134 ","pages":"Article 108881"},"PeriodicalIF":2.7,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142440997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unwinding DNA strands by single-walled carbon nanotubes: Molecular docking and MD simulation approach","authors":"Ghazal Borhan, Mehdi Sahihi","doi":"10.1016/j.jmgm.2024.108882","DOIUrl":"10.1016/j.jmgm.2024.108882","url":null,"abstract":"<div><div>Despite the growing research into the use of carbon nano-tubes (CNTs) in science and medicine, concerns about their potential toxicity remain insufficiently studied. This study utilizes molecular docking calculations combined by molecular dynamics simulations to investigate the dynamic intricacies of the interaction between single-walled carbon nanotubes (swCNTs) and double-stranded DNA (dsDNA). By examining the influence of swCNT characteristics such as length, radius, and chirality, our findings shed light on the complex interplay that shapes the binding affinity and stability of the dsDNA-swCNT complex. Molecular docking results identify a zigzag swCNT, with a radius of 0.16 Å and a length of 38 Å, as exhibiting the highest binding affinity with dsDNA (−23.9 kcal/mol). Comprehensive analyses, spanning docking results, binding energies, RMSD, radius of gyration, and potential of mean force (PMF) profiles, provide a detailed understanding of the denaturation dynamics. The PMF profiles reveal the thermodynamic feasibility of the DNA-CNT interaction, outlining distinct energy landscapes and barriers: when the selected swCNT binds within the dsDNA groove, the system becomes trapped at the first and second local energy minima, occurring at 1.48 nm and 1.00 nm, respectively. Intramolecular hydrogen bond calculations show a significant reduction, affirming the denaturing effect of swCNTs on DNA. Furthermore, the study reveals a significant reduction in the binding affinity of Ethidium Bromide (EB) to dsDNA following its interaction with swCNT, with a decrease in EB binding to dsDNA of approximately 13.2 %. This research offers valuable insights into the toxic effects of swCNTs on dsDNA, contributing to a rationalization of the cancerous potential of swCNTs.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108882"},"PeriodicalIF":2.7,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Insights into the binding recognition and computational design of IL-2 muteins with enhanced predicted binding affinity to the IL-2 receptor α","authors":"Thanapon Charoenwongpaiboon , Methus Klaewkla","doi":"10.1016/j.jmgm.2024.108883","DOIUrl":"10.1016/j.jmgm.2024.108883","url":null,"abstract":"<div><div>Interleukin-2 (IL-2) is an immune system regulator that has received approval for cancer treatment. However, high-dose IL-2 therapy has seen restricted use due to its low efficacy and on-target toxicity. To enhance the effectiveness of IL-2 therapy, it is essential to engineer IL-2 molecules to enhance their specificity toward target cell populations. In this study, molecular dynamics (MD) simulations and Rosetta software were utilized to design novel high-affinity IL-2Rα-binding IL-2 muteins. MD simulations were used to identify the target residues of IL-2 for design, and Rosetta software were then employed to predict potential IL-2 muteins with higher binding affinity toward IL-2Rα. Rosetta generated two potential designed IL-2 muteins. The results of the MD validation and MM/GBSA analysis indicated that both designed IL-2 muteins exhibited greater predicted binding affinities toward IL-2Rα than that of the native proteins. RMSF analysis demonstrated that the structural fluctuations of free IL-2 and designed muteins were similar, indicating that the mutations did not alter the intramolecular force responsible for IL-2's stability and folding. These designed IL-2 muteins may have potential benefits for cancer immunotherapy.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108883"},"PeriodicalIF":2.7,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Adsorption dynamics of heavy oil droplets on silica: Effect of asphaltene anionic carboxylic","authors":"Peng Cui , Heng Zhang , Shiling Yuan","doi":"10.1016/j.jmgm.2024.108880","DOIUrl":"10.1016/j.jmgm.2024.108880","url":null,"abstract":"<div><div>Understanding the adsorption behavior of asphaltene molecules on the surfaces of oil reservoir solids is essential for optimizing oil recovery processes. This study employed molecular dynamics simulations to investigate the adsorption behavior of oil droplets composed of charged and neutral asphaltenes on silica surfaces. The results revealed that oil droplet containing anionic asphaltene molecules were more likely to adsorb onto silica surfaces and exhibited greater resistance to detachment compared to oil droplet containing neutral asphaltene molecules. Specifically, anionic asphaltene molecules tended to accumulate at the oil-water-silica interface, whereas neutral asphaltene molecules primarily adsorbed near the oil-water interface. These findings provide valuable insights into the differing adsorption dynamics of charged and neutral asphaltene molecules on silica surfaces.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108880"},"PeriodicalIF":2.7,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Local potential energy density – A DFT analysis and the local binding energy in complexes with multiple interactions","authors":"Caio L. Firme","doi":"10.1016/j.jmgm.2024.108879","DOIUrl":"10.1016/j.jmgm.2024.108879","url":null,"abstract":"<div><div>A recently developed method, so-called local potential energy density, LPED, provides the binding energy density of intra/intermolecular interactions. The LPED cannot directly give the binding energy of intra/intermolecular interactions. However, it can indirectly give the binding energy through the linear equation between LPED and supramolecular binding energy, SME. In addition, the LPED can be used to obtain the SME of local or individual interactions indirectly for the case of complexes with multiple interactions, which cannot be obtained for any other method to our knowledge. The calculation of the LPED was evaluated with three different levels of theory using density functional methods. The linearity of LPED and SME between the reference level of theory (ωB97X-D/aug-cc-pVTZ) and the other levels of theory are similar among the studied levels of theory. In addition, LPED was used indirectly to obtain the local binding energy of intermolecular interactions of complexes with multiple interactions, such as the EDTA-Ca<sup>+2</sup> and the fosfomycin-Ca<sup>+2</sup>.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108879"},"PeriodicalIF":2.7,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hayet Belghit, Manuel Dauchez, Jean-Marc Crowet, Jessica Jonquet-Prevoteau
{"title":"Dy-SheHeRASADe: A representation of the β sheet dynamics through surface descriptors","authors":"Hayet Belghit, Manuel Dauchez, Jean-Marc Crowet, Jessica Jonquet-Prevoteau","doi":"10.1016/j.jmgm.2024.108876","DOIUrl":"10.1016/j.jmgm.2024.108876","url":null,"abstract":"<div><div>Molecular dynamics (MD) simulations are important tools for studying the dynamic motions of macromolecules at the atomic level. With the increasing capabilities of high performance computing, MD simulations are becoming more widely used. This allows molecular modelers to simulate the molecular behavior of large molecular architectures for much longer trajectories. Appropriate visualization of MD trajectories is becoming essential to provide an immediate and intuitive understanding of a molecule’s dynamics and function. In this study, we implement a novel 3D graphical representation, Dynamical Sheets Helper for RepresentAtion of SurfAce Descriptors (Dy-SheHeRASADe), to visualize the <span><math><mi>β</mi></math></span> sheet secondary structures of proteins in the context of molecular dynamics. Dy-SheHeRASADe is developed in UnityMol, an open source molecular viewer and prototyping platform. We considered <span><math><mi>β</mi></math></span> sheet fluctuations and hydrogen bond formation during molecular dynamics simulations to characterize the parts of <span><math><mi>β</mi></math></span> sheets with large motions or with labile bonds. We propose two visualization modes based on a surface representation of the <span><math><mi>β</mi></math></span> sheets calculated according to the positions of the <span><math><mi>α</mi></math></span> carbons and the hydrogen bonds between the <span><math><mi>β</mi></math></span> strands. The volumetric mode, in which this surface is enclosed in a semi-transparent volume that represents the fluctuation zone of the sheet during dynamics. The heatmap mode, in which the surface is colored according to the amplitude values of the <span><math><mi>α</mi></math></span> carbons. In addition, we quantify the <span><math><mi>β</mi></math></span> sheet fluctuations by displaying the values of the largest and smallest movements of the <span><math><mi>β</mi></math></span> sheets, the surface area of the sheets, and the number of hydrogen bonds.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108876"},"PeriodicalIF":2.7,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142391145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploring the optical properties of naphdiyne sheet: First-principles study","authors":"Roya Majidi","doi":"10.1016/j.jmgm.2024.108877","DOIUrl":"10.1016/j.jmgm.2024.108877","url":null,"abstract":"<div><div>Naphdiyne sheet is a two-dimensional carbon-based structure composed of naphthyl rings and acetylenic linkages. The optical characteristics of naphdiyne sheets are investigated using density functional theory. The results showed that this sheet is suitable for energy storage systems due to its high dielectric constant. The dielectric constant of naphdiyne is higher than that of graphene. The refractive index, absorption, reflection, and transmission coefficients are calculated based on the dielectric function. A notable optical absorption is observed across a wide energy range for parallel polarization. The transparency of this material is evident in its reflection and transmission constants, particularly in high-energy regions. The findings suggest that the naphdiyne sheets hold promise for use in nanoelectronics and optoelectronics.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108877"},"PeriodicalIF":2.7,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142381076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Bjerrum defects in s-II gas hydrate","authors":"Nevin Uras-Aytemiz , F. Mine Balcı","doi":"10.1016/j.jmgm.2024.108878","DOIUrl":"10.1016/j.jmgm.2024.108878","url":null,"abstract":"<div><div>The energy and structure of Bjerrum defects in structure II gas hydrates were investigated by using first-principle calculations for finite-size clusters and periodic 3D lattice systems. The formation energies of these defects were calculated for the first time when the cages of the structure II structure were completely empty and the large cage was filled with a THF molecule. Analogous to findings in ice structures, one of the hydrogen atoms forming the <em>D</em> defect was noted to orient toward the cage. If the excess proton resides in the large cage, it acts as an attraction center for the polar guest molecule, i.e., THF. Therefore, the large cage guest THF molecule stabilizes the <em>D/L</em> defect pair and isolated <em>D/L</em> defect formation energies by forming hydrogen bonds with the <em>D</em> defect. In such cases, the defect structure representing a <em>D/L</em> defect pair containing a THF molecule interacting with one of the hydrogen atoms of the <em>D</em> defect mirrors the guest-induced ones. Notably, the classical Bjerrum defect and the guest-induced Bjerrum defect exhibit a similar phenomenon in defective structures. Contrary to existing literature, it is evident that guest-induced Bjerrum defects involve both the <em>L</em> and <em>D</em> components. The insights gained from this study could potentially offer an alternative perspective to understand various experimental observations, such as those related to dielectric and NMR properties.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108878"},"PeriodicalIF":2.7,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142381075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluation of AlphaFold3 for the fatty acids docking to human fatty acid-binding proteins","authors":"Ki Hyun Nam","doi":"10.1016/j.jmgm.2024.108872","DOIUrl":"10.1016/j.jmgm.2024.108872","url":null,"abstract":"<div><div>Human fatty acid-binding proteins (FABPs) are involved in many aspects of lipid metabolism, such as the uptake, transport, and storage of lipophilic molecules, as well as cellular functions. Understanding how FABPs recognize fatty acids (FAs) is crucial for identifying FABP function and applications, such as in inhibitor design or biomarker development. The recently developed AlphaFold3 (AF3) demonstrates significantly higher accuracy than other prediction tools, particularly in predicting protein–ligand interactions with state-of-the-art docking tools. Studies on whether AF3 can be used to identify the FAs of FABP are lacking. To assess the accuracy of FA docking to FABPs using AF3, models of FA docked into FABP generated using AF3 were compared with experimentally determined FA-bound FABP structures. FA ligands in AF3 structures docked reliably into the FA-binding pocket of FABPs; however, the detailed binding configuration of most FA ligands docked into FABPs and the interaction between FA and FABP determined using AF3 and experimentally differed. These results will aid in understanding FA docking to FABPs and other FA-binding proteins using AF3.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108872"},"PeriodicalIF":2.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modification of MM force fields around heme-Fe in the CYP–ligand complex and ab initio FMO calculations for the complex","authors":"Yoshinobu Nagura, Haruna Sabishiro, Nagomi Chimura, Masayuki Yuguchi, Narutoshi Tada, Daichi Takimoto, Noriyuki Kurita","doi":"10.1016/j.jmgm.2024.108875","DOIUrl":"10.1016/j.jmgm.2024.108875","url":null,"abstract":"<div><div>Cytochrome P450 (CYP) enzymes play essential roles in the synthesis and metabolic activation of physiologically active substances. CYP has a prosthetic heme (iron protoporphyrin IX) in its active center, where Fe ion (heme-Fe) is deeply involved in enzymatic reactions of CYP. To precisely describe the structure and electronic states around heme-Fe, we modified the force fields (FFs) around heme-Fe in molecular mechanics (MM) simulations and conducted <em>ab initio</em> fragment molecular orbital (FMO) calculations for the CYP–ligand complex. To describe the coordination bond between heme-Fe and its coordinated ligand (ketoconazole), we added FF between heme-Fe and the N atom of ketoconazole, and then the structure of the complex was optimized using the modified FF. Its adequacy was confirmed by comparing the MM-optimized structure with the X-ray crystal one of the CYP–ketoconazole complex. We also performed 100 ns molecular dynamics simulations and revealed that the coordination bonds around heme-Fe were maintained even at 310 K and that the CYP–ketoconazole structure was kept similar to the X-ray structure. Furthermore, we investigated the electronic states of the complex using the <em>ab initio</em> FMO method to identify the CYP residues and parts of ketoconazole that contribute to strong binding between CYP and ketoconazole. The present procedure of constructing FF between heme-Fe and ketoconazole can be applicable to other CYP–ligand complexes, and the modified FF can provide their accurate structures useful for predicting the specific interactions between CYP and its ligands.</div></div>","PeriodicalId":16361,"journal":{"name":"Journal of molecular graphics & modelling","volume":"133 ","pages":"Article 108875"},"PeriodicalIF":2.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}