Biochimica et biophysica acta. Biomembranes最新文献

{"title":"Bacterial cell susceptibility to the antimicrobial peptide MP1 depends on membrane lipid packing","authors":"L. Stefania Vargas-Velez,&nbsp;Florencia Hellriegel ,&nbsp;Mariela R. Monti,&nbsp;Natalia Wilke","doi":"10.1016/j.bbamem.2025.184486","DOIUrl":"10.1016/j.bbamem.2025.184486","url":null,"abstract":"<div><div>Polybia-MP1 is an antimicrobial peptide with broad-spectrum activity, but with varying efficacy against different bacterial strains. It is proposed to act on the cell membrane, and therefore, the higher tolerance of some strains may be attributed to differences in their membrane properties. Considering this hypothesis, we studied the biophysical properties of the membrane for bacteria with different susceptibility to the peptide. We found that high tolerance to the peptide correlates with lipid membranes of high microviscosity and stiffness, factors that in turn depend on lipid packing. We propose that high lipid packing slows peptide penetration into membranes and the subsequent disruption of the bilayer, limiting its action. Therefore, we conclude that lipid packing is an important factor determining the differences in susceptibility among bacteria. This interplay between peptide action and membrane properties hinders the development of bacterial resistance to the peptide, since alterations in lipid composition lead to various changes in membrane properties, which in turn have differential effects on cell function.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184486"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145562492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Unveiling the impact of membrane fluidity in shaping lipid-based drug delivery systems development.” [Biochim. Biophys. Acta (BBA) – Biomembr. Volume 1868, Issue 1, January 2026, 184461]","authors":"Mariana Biscaia-Caleiras ,&nbsp;Ana Sofia Lourenço ,&nbsp;João Nuno Moreira ,&nbsp;Sérgio Simões","doi":"10.1016/j.bbamem.2025.184479","DOIUrl":"10.1016/j.bbamem.2025.184479","url":null,"abstract":"","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184479"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145470391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transmembrane channel-like 4 (TMC4) could act as a negative regulator of KCNQ1 (Kv7.1) potassium channel","authors":"Hirota Aoyagi,&nbsp;Koya Kawaguchi,&nbsp;Saori Yano-Nashimoto,&nbsp;Soichiro Yamaguchi","doi":"10.1016/j.bbamem.2025.184460","DOIUrl":"10.1016/j.bbamem.2025.184460","url":null,"abstract":"<div><div>TMC4 is a member of the transmembrane channel-like (TMC) protein family. In this family, TMC1 and TMC2 are thought to form the mechano-electrical transduction (MET) channel in the inner ear. On the other hand, the intrinsic functions of the other TMC family members (TMC3-8) are largely unknown. KCNQ1 (Kv7.1) channel is a voltage-gated potassium channel and plays crucial physiological roles with its auxiliary subunits, KCNE proteins (e.g. KCNQ1/KCNE1 complex contributes to cardiac repolarization, and KCNQ1/KCNE3 complex participates in epithelial ion transport). Recently, it was reported that TMC1 and TMC2 interacted with KCNQ1 and suppressed its K⁺ currents. However, the relationships between KCNQ1 and the other TMC proteins have not been examined. Here, we show a novel interaction and a functional association between overexpressed TMC4 and KCNQ1. The Bead Halo assay and FRET analysis revealed the physical interaction between these two proteins. Whole-cell patch clamp recording demonstrated that co-expression of TMC4 reduced KCNQ1 current densities without altering their voltage dependence and activation kinetics. This effect was also observed in the KCNQ1/KCNE1 and KCNQ1/KCNE3 channel complexes. A structural prediction using AlphaFold-Multimer suggested possible interaction sites between TMC4 and KCNQ1. Mutageneses, followed by patch clamp recording, suggested that specific amino acid residues at these sites contribute to the inhibitory effect of TMC4. These results indicate that TMC4 could function as a negative regulator of the KCNQ1 channel. Our findings could enhance the understanding of KCNQ1 channel regulation and propose potential research directions on the function of TMC4 under various physiological and pathological conditions.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184460"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145228384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contribution to the special BBA issue dedicated to Joachim Seelig from lipid bilayers to the innate immune system","authors":"Anna Seelig","doi":"10.1016/j.bbamem.2025.184483","DOIUrl":"10.1016/j.bbamem.2025.184483","url":null,"abstract":"<div><div>This personal review in memory of Joachim Seelig covers half a century of membrane biophysics. The topics chosen give insight into the structure and function of our innate immune system, consisting in the membranes covering the external and internal body surfaces in contact with the outside world. Their core is the lipid bilayer in its liquid crystalline state. We investigated its average structure and fluidity by deuterium-nuclear magnetic resonance spectroscopy (D-NMR) using selectively deuterated lipids. Close to the lipid-water interface, lipids retain a defined average structure with the glycerol backbone oriented perpendicular to the membrane surface. The characteristic structure of lipids remains in the presence of transmembrane proteins and guarantees a tight membrane packing near the aqueous phases. The order of lipid segments remains approximately constant decreasing only towards the membrane center. Were cells surrounded by lipids only, hydrophobic molecules would nevertheless penetrate the membranes and reach the nucleus, the smaller ones more rapidly and the larger one more slowly. To protect cells from intruding mutagenic compounds, a significant number of defense proteins have evolved, including ATP binding cassette (ABC) transporters and pattern recognition receptors (PRR). Interestingly, the different defense proteins recognize compounds that carry specific hydrogen bond acceptor patterns and could interfere with DNA or RNA. ABC transporters and pattern recognition receptors remove them from the lipid bilayer before they reach the cytosol to prevent mutagenesis. While these proteins are well known to contribute to multidrug resistance (MDR), their significant role in innate immunity only starts to emerge.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184483"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145511186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the role of lipid monolayer properties in ACE2 and TMPRSS2 incorporation","authors":"Kevin F. dos Santos ,&nbsp;Luciano Caseli","doi":"10.1016/j.bbamem.2025.184480","DOIUrl":"10.1016/j.bbamem.2025.184480","url":null,"abstract":"<div><div>The entry of SARS-CoV-2 into host cells primarily involves binding of the viral spike (S) protein to the angiotensin-converting enzyme 2 (ACE2) receptor and subsequent fusion of the viral envelope with the host membrane, a process facilitated by host proteases such as transmembrane serine protease 2 (TMPRSS2). Lipid raft domains are believed to influence this internalization pathway, although the precise localization and functional roles of ACE2 and TMPRSS2 within these domains remain unclear. In this study, we employed mixed Langmuir monolayers—representing the plasma membrane (PM) and two lipid raft models (LR and Chol/SM)—to investigate the interfacial behavior of ACE2 and TMPRSS2 fragments. Using tensiometric, microscopic, and spectroscopic techniques, we found that both proteins were more readily incorporated into fluid and loosely packed monolayers (PM and LR), leading to increased molecular area and disruption of lipid organization. In contrast, the tightly packed Chol/SM monolayer exhibited minimal changes, indicating limited protein insertion. These results demonstrate that monolayer composition and packing significantly influence protein incorporation and arrangement, which may in turn affect their accessibility to viral components. Although lipid rafts are proposed sites of ACE2 and TMPRSS2 enrichment, our findings suggest that their structural organization within such domains may be modulated by the physicochemical properties of the surrounding lipid environment, with potential implications for SARS-CoV-2 infection mechanisms.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184480"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145430323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing biologically-relevant cell membrane models with natural lipid mixtures","authors":"Krishna Chaithanya Batchu ,&nbsp;Giacomo Corucci ,&nbsp;Valérie Laux ,&nbsp;Frank Gabel ,&nbsp;Giovanna Fragneto ,&nbsp;Alessandra Luchini","doi":"10.1016/j.bbamem.2025.184474","DOIUrl":"10.1016/j.bbamem.2025.184474","url":null,"abstract":"<div><div>Cell membranes provide vital biological functions by separating the cell components from the surrounding environment and providing a bioactive interface for several biological processes. The direct extraction of intact cell membranes and their investigation with biophysical methods is heavily limited by their compositional complexity and intrinsic fragility. Therefore, over the years, membrane models including vesicles, lipid monolayers, supported lipid bilayers and lipid multilayers, were suggested as alternatives to study the physico-chemical properties of cell membranes. These membrane models are typically produced with 1-3 synthetic lipid species and their application is therefore restricted by their composition, being too simple as compared to native cell membranes.</div><div>In this review, we discuss the latest efforts towards producing more biologically relevant membrane models by utilizing natural lipid extracts. These are produced by extracting and purifying lipids expressed by different types of microbial cells. In part I, we present a detailed discussion of the methods currently available for obtaining the extracts, and in part II, we discuss how to use them for preparing cell membrane models and characterizing their structure. The majority of the discussed studies refer to <em>Escherichia coli</em> and <em>Pichia pastoris</em> glycerophospholipid extracts. For these extracts, optimized extraction and purification protocols were recently reported, which enable the efficient production of both hydrogenous and deuterated natural lipid mixtures. Deuterated lipids are of particular relevance for membrane characterization with techniques such as NMR, vibrational spectroscopies, and neutron scattering. In part III, we provide some future perspectives on the application of the currently available natural lipid extracts as well as on the development of protocols for the production of extracts from other cell types, e.g. mammalian cells and for isolating individual lipid molecules from such extracts. We also discuss methods to design genetically engineer microbial strains for enhancing the biosynthesis of target lipid molecules.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184474"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145298260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TRAP mediated conformational changes of the human Sec61 channel","authors":"Nidhi Sorout,&nbsp;Volkhard Helms","doi":"10.1016/j.bbamem.2025.184488","DOIUrl":"10.1016/j.bbamem.2025.184488","url":null,"abstract":"<div><div>The integral membrane pore Sec61 catalyzes the translocation of many secretory precursor proteins into the endoplasmic reticulum, as well as the insertion of transmembrane proteins into the cell and organellar membranes. Precursor proteins that possess weak signal peptides frequently require presence of the accessory membrane protein TRAP. Structural biology has recently established that TRAP shares several contact sites with Sec61, though not by an extended binding interface. However, how TRAP mechanistically supports the translocation of precursor proteins is still partially unresolved. Here, atomistic molecular dynamics simulations revealed that TRAP binding keeps Sec61 in a partially opened state, with looser packing of its transmembrane helices. TRAP maintained a partially opened Sec61 lateral gate and pore ring, shifting the plug helix towards an open conformation. These observations corroborate the existing model of how TRAP may support translocation of client precursor proteins with weak signal peptides.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184488"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145614272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Interaction of N-terminal peptide analogues of the Na+,K+-ATPase with membranes” [BBA Biomembr. 1860 (6) (2018) 1282–1291]","authors":"Khoa Nguyen ,&nbsp;Alvaro Garcia ,&nbsp;Marc-Antoine Sani ,&nbsp;Vikas Dubey ,&nbsp;Daniel Clayton ,&nbsp;Giovanni Dal Poggetto ,&nbsp;Flemming Cornelius ,&nbsp;Richard J. Payne ,&nbsp;Frances Separovic ,&nbsp;Himanshu Khandelia ,&nbsp;Ronald J. Clarke","doi":"10.1016/j.bbamem.2025.184482","DOIUrl":"10.1016/j.bbamem.2025.184482","url":null,"abstract":"","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184482"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145480895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling the impact of membrane fluidity in shaping lipid-based drug delivery systems development","authors":"Mariana Biscaia-Caleiras ,&nbsp;Ana Sofia Lourenço ,&nbsp;João Nuno Moreira ,&nbsp;Sérgio Simões","doi":"10.1016/j.bbamem.2025.184461","DOIUrl":"10.1016/j.bbamem.2025.184461","url":null,"abstract":"<div><div>Membrane fluidity is a fundamental property extensively studied in biological membranes and biophysical research, where it is critical to understanding membrane structure and function. However, its application in the development and manufacturing of lipid-based drug delivery systems, such as liposomes and lipid nanoparticles, remains underexplored. This mini-review shifts the focus toward the practical implications of membrane fluidity in pharmaceutical formulation and manufacturing. We highlight key factors influencing fluidity, such as temperature, lipid composition, and cholesterol content, and emphasize how understanding and controlling fluidity can serve as a critical quality attribute. The importance of these factors in modulating membrane dynamics is emphasized, revealing their potential to optimize liposomal formulations and manufacturing processes. Fluorescent probes such as DPH and Laurdan are also discussed for their ability to monitor fluidity in real-time, each presenting distinct advantages and limitations. Although its crucial role in lipid-based drug delivery systems, membrane fluidity remains a largely overlooked property. Deeper investigation is essential to fully understand its influence on membrane stability, therapeutic efficacy, and scalability. This mini-review advocates for a paradigm shift: recognizing membrane fluidity as a critical quality attribute that can be integrated into formulation development and industrial manufacturing frameworks to better predict and control product performance and process robustness.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184461"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145228377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immune antibodies recognizing the stem region of SARS-CoV-2 spike protein: Molecular modeling and in vitro study of synthetic peptides presentation to the antibodies","authors":"Elena T. Aliper ,&nbsp;Ivan M. Ryzhov ,&nbsp;Polina S. Obukhova ,&nbsp;Alexander B. Tuzikov ,&nbsp;Oxana E. Galanina ,&nbsp;Marina M. Ziganshina ,&nbsp;Gennady T. Sukhikh ,&nbsp;Nikolay A. Krylov ,&nbsp;Stephen M. Henry ,&nbsp;Roman G. Efremov ,&nbsp;Nicolai V. Bovin","doi":"10.1016/j.bbamem.2025.184472","DOIUrl":"10.1016/j.bbamem.2025.184472","url":null,"abstract":"<div><div>Antibodies to peptide 1147 (amino acids 1147–61) of the SARS-CoV-2 S protein are highly diagnostic. Peptide 1147, although located in a region that is partly spatially hidden in the intact protein, is not subject to mutations, suggesting therapeutic potential. The aim of this study was to elucidate the architecture of this region and the way in which it is presented to antibodies. As a model system, this peptide carrying a single lipophilic tail and the same peptide carrying a lipophilic tail at both ends (pseudocyclic) were incorporated into a lipid membrane. Isolated anti-1147 antibodies interacted with it regardless of how the peptide was presented, be that freely exposed via the N-terminus, organized as a pseudocycle, or adsorbed on the surface. Molecular dynamics simulations showed that peptide 1147 is capable of closely approaching the membrane. Analysis of the surface properties of peptide 1147 in membrane-bound states and in particular functional conformations in the full-sized S protein reveals an interface for interaction with antibodies. Interestingly, the latter bears similarities to one published peptide-antibody complex. However, these antibodies, in spite of their high diagnostic significance, show no virus-neutralizing activity, indicating that peptide 1147 has no therapeutic value as a synthetic vaccine.</div></div>","PeriodicalId":8831,"journal":{"name":"Biochimica et biophysica acta. Biomembranes","volume":"1868 1","pages":"Article 184472"},"PeriodicalIF":2.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145290726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}