Biophysical chemistry最新文献

{"title":"Urineprint of high-altitude: Insights from analyses of urinary biomarkers and bio-physical-chemical features of extracellular vesicles","authors":"Serena Pilato ,&nbsp;Simona Mrakic-Sposta ,&nbsp;Vittore Verratti ,&nbsp;Carmen Santangelo ,&nbsp;Stefano di Giacomo ,&nbsp;Samanta Moffa ,&nbsp;Antonella Fontana ,&nbsp;Tiziana Pietrangelo ,&nbsp;Federica Ciampini ,&nbsp;Sofia Bonan ,&nbsp;Pamela Pignatelli ,&nbsp;Carmine Noce ,&nbsp;Pietro di Profio ,&nbsp;Michele Ciulla ,&nbsp;Danilo Bondi ,&nbsp;Fabrizio Cristiano","doi":"10.1016/j.bpc.2024.107351","DOIUrl":"10.1016/j.bpc.2024.107351","url":null,"abstract":"<div><div>Humans exposed to altitude hypoxia experience dysfunctions of the urinary system. As a non-invasive, easily manageable and informative biological sample, urine represents a relevant matrix for detecting clinical impairments of urinary system, as well as alterations of other systems and extracellular vesicles (EVs) biology during high-altitude expeditions. Nevertheless, gaps exist in the comprehensive assessment of dysfunction, molecular burden and EVs biology due to high-altitude acute exposure. This study aimed to find a biophysical and biochemical signature of urinary EVs for hypoxia-induced changes in urinary function, putatively accompanied by an oxinflammatory burden. Urine samples of 15 participants were sampled at low and high-altitude during an Alpine project (7 women and 8 men, aged 24-to-63 years and with BMI 17.93-to-30.76 kg/m²) and analysed for: creatinin and albumin, lipid peroxidation, IL6, NO derivatives; atomic force microscopy and Raman spectroscopy were carried out after urinary EVs were isolated through sucrose-gradient ultracentrifugation. Albumin-to-creatinin ratio increased at high altitude, as did IL6 and 8-isoprostane. AFM showed a globular and flattened shape of EVs, although several samples were characterized by a lot of contaminants and EVs lost their prototypal spherical shape; EVs comprehensively maintained their morphology at high altitude. Raman spectroscopy revealed some typical phospholipidic-like pattern, often masked by contaminants of spectra that most often refer to high-altitude samples. Collectively, short-term exposure to altitude hypoxia increased renal concentrating ability, produced non-pathological impairment or renal function, and triggered an oxyinflammatory burden with heterogeneous response of NO system. The combination of AFM and Raman spectroscopy revealed that EVs collected at high altitude more likely are fused together and incorporated into a sediment matrix, and contain contaminants peaks that make the purification process less efficient. The combination of analytical procedures as in the present study offers novel possibilities to detect the biological and clinical effects of high altitude on renal system.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107351"},"PeriodicalIF":3.3,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142647000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics of i-motif folding within the duplex context","authors":"Rugiya Alieva ,&nbsp;Anna Keshek ,&nbsp;Timofei Zatsepin ,&nbsp;Victor Orlov ,&nbsp;Andrey Aralov ,&nbsp;Elena Zavyalova","doi":"10.1016/j.bpc.2024.107350","DOIUrl":"10.1016/j.bpc.2024.107350","url":null,"abstract":"<div><div>Non-canonical nucleic acid structures possess an ability to interact selectively with proteins, thereby exerting influence over various intracellular processes. Numerous studies indicate that genomic G-quadruplexes and i-motifs are involved in the regulation of transcription. These structures are formed temporarily during the unwinding of the DNA double helix; and their direct determination is a rather difficult task. In addition, i-motif folding is pH-dependent, with most i-motifs having low stability at neutral pH. However, some genomic i-motifs with long cytosine repeats were shown to be stable at pH 7.3, suggesting their functionality within the nucleus. Here we studied pH-dependent behavior of a model i-motif with flanking sequences that forms a duplex motif. Kinetic studies on bimodular structures with cytosine residues replaced with an environment-sensitive fluorescent label reveal the stabilization of the i-motif structure near the i-motif-duplex junction. These results highlight the importance of the natural environment of i-motifs for the correct assessment of their stability.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107350"},"PeriodicalIF":3.3,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638345","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":"Supramolecular arrangements in human amyloid tissues using SAXS","authors":"N.S. Mohd Nor Ihsan ,&nbsp;S.F. Abdul Sani ,&nbsp;L.M. Looi ,&nbsp;Dharini Pathmanathan ,&nbsp;P.L. Cheah ,&nbsp;S.F. Chiew ,&nbsp;Sirinart Chio-Srichan ,&nbsp;Siriwat Soontaranon ,&nbsp;D.A. Bradley","doi":"10.1016/j.bpc.2024.107349","DOIUrl":"10.1016/j.bpc.2024.107349","url":null,"abstract":"<div><div>Amyloid diseases are characterized by the accumulation of misfolded protein aggregates in human tissues, pose significant challenges for both diagnosis and treatment. Protein aggregations known as amyloids are linked to several neurodegenerative conditions including Alzheimer's disease, Parkinson's disease, and systemic amyloidosis. The key goal of this research is to employ Small-Angle X-ray Scattering (SAXS) to examine the supramolecular structures of amyloid aggregates in human tissues. We present the structural analysis of amyloid using SAXS, which is employed directly to analyze thin tissue samples without damaging the tissues. This technique provides size and shape information of fibrils, which can be used to generate low-resolution 2D models. The present study investigates the structural changes in amyloid fibril axial d-spacing and scattering intensity in different human tissues, including kidney, heart, thyroid, and others, while also accounting for the presence of triglycerides in these tissues. Tissue structural components were examined at momentum transfer values between q = 0.2 nm⁻¹ and 1.5 nm⁻¹. The d-spacing is a critical parameter in SAXS that provides information about the periodic distances between structures within a sample. From the supramolecular SAXS patterns, the axial d-spacing of fibrils in amyloid tissues is prominent and exists within the 3rd to 10th order, compared to that of healthy tissues which do not have notable peak orders. The axial period of fibrils in amyloid tissues is within the scattering vector range 57.40–64.64 nm⁻¹ while in normal tissues the range is between 60.68 and 61.41 nm⁻¹, which is 3.0 nm⁻¹ smaller than amyloid-containing tissues. Differences in d-spacing are often correlate with distinct pathological mechanisms or stages of disease progression. The application of SAXS to investigate amyloid structures in human tissues has enormous potential to further knowledge of amyloid disorders. This work will open the path for novel diagnostic instruments and therapeutic strategies meant to reduce the burden of amyloid-related diseases by offering a thorough structural examination of amyloid aggregates.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107349"},"PeriodicalIF":3.3,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142638346","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":"Characterization of a novel salt- and solvent-tolerant esterase Dhs82 from soil metagenome capable of hydrolyzing estrogenic phthalate esters","authors":"Yuanyan Wang ,&nbsp;Chunmei Deng ,&nbsp;Xin Wang","doi":"10.1016/j.bpc.2024.107348","DOIUrl":"10.1016/j.bpc.2024.107348","url":null,"abstract":"<div><div>Esterases that can function under extreme conditions are important for industrial processing and environmental remediation. Here, we report the identification of a salt- and solvent-tolerant esterase, Dhs82, from a soil metagenomic library. Dhs82 prefers short-chain <em>p</em>-nitrophenyl (<em>p</em>-NP) esters and exhibits enzymatic activity up to 1460 ± 61 U/mg towards <em>p</em>-NP butyrate. Meanwhile, Dhs82 can catalyze the hydrolysis of dialkyl phthalate esters, especially the widely-used diethyl phthalate (DEP), dipropyl phthalate (DPP) and di-n-butyl phthalate (DBP). Importantly, as an acidic protein with negative charges dominating its surface, Dhs82 is highly active and extraordinarily stable at high salinity. This property is quite rare among previously reported esterases/hydrolases capable of degrading phthalate esters (PAEs). In addition, Dhs82 activity can be significantly enhanced in the presence of solvents over a concentration range of 10–30 % (<em>v</em>/v). Notably, Dhs82 also showed high stability towards these solvents and solvent concentrations as high as 50–60 % (<em>v</em>/v) are required to inactivate Dhs82. Furthermore, molecular docking revealed the key residues, including the catalytic triad (Ser156, His281, and Asp251) and the surrounding Gly84 and Gly85, involved in the interaction of Dhs82 with DBP, depicting how Dhs82 degrades PAEs as a family IV esterase. Together, these diverse properties make Dhs82 a valuable candidate for both basic research and biotechnological applications.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107348"},"PeriodicalIF":3.3,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142614295","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":"The Drosophila RNA binding protein Hrp48 binds a specific RNA sequence of the msl-2 mRNA 3’ UTR to regulate translation","authors":"Andrea Lomoschitz ,&nbsp;Julia Meyer ,&nbsp;Tanit Guitart ,&nbsp;Miroslav Krepl ,&nbsp;Karine Lapouge ,&nbsp;Clara Hayn ,&nbsp;Kristian Schweimer ,&nbsp;Bernd Simon ,&nbsp;Jiří Šponer ,&nbsp;Fátima Gebauer ,&nbsp;Janosch Hennig","doi":"10.1016/j.bpc.2024.107346","DOIUrl":"10.1016/j.bpc.2024.107346","url":null,"abstract":"<div><div>Repression of <em>msl-2</em> mRNA translation is essential for viability of <em>Drosophila melanogaster</em> females to prevent hypertranscription of both X chromosomes. This translational control event is coordinated by the female-specific protein Sex-lethal (Sxl) which recruits the RNA binding proteins Unr and Hrp48 to the 3’ untranslated region (UTR) of the <em>msl-2</em> transcript and represses translation initiation. The mechanism exerted by Hrp48 during translation repression and its interaction with <em>msl-2</em> are not well understood. Here we investigate the RNA binding specificity and affinity of the tandem RNA recognition motifs of Hrp48. Using NMR spectroscopy, molecular dynamics simulations and isothermal titration calorimetry, we identified the exact region of <em>msl-2</em> 3’ UTR recognized by Hrp48. Additional biophysical experiments and translation assays give further insights into complex formation of Hrp48, Unr, Sxl and RNA. Our results show that Hrp48 binds independent of Sxl and Unr downstream of the E and F binding sites of Sxl and Unr to <em>msl-2</em>.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107346"},"PeriodicalIF":3.3,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142590115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding Cu+2 binding with DNA: A molecular dynamics study comparing Cu2+ and Mg2+ binding to the Dickerson DNA","authors":"Angad Sharma,&nbsp;Hari O.S. Yadav,&nbsp;Pradipta Bandyopadhyay","doi":"10.1016/j.bpc.2024.107347","DOIUrl":"10.1016/j.bpc.2024.107347","url":null,"abstract":"<div><div>Cu²⁺ ions led DNA damage by reactive oxygen species (ROS) is widely known biological phenomena. The ionic radii of Cu²⁺ and Mg²⁺ being similar, the binding of Cu²⁺ ions to DNA is expected to be similar to that of the Mg²⁺ ions. However, little is known how Cu²⁺ ions bind in different parts (phosphate, major and minor grooves) of a double-strand (ds) DNA, especially at atomic level. In the present study, we employ molecular dynamic (MD) simulations to investigate the binding of Cu²⁺ ions with the Dickerson DNA, a B-type dodecamer double stranded (ds) DNA. The binding characteristics of Cu²⁺ and Mg²⁺ ions with this dsDNA are compared to get an insight into the differences and similarities in binding behavior of both ions. Unlike Mg²⁺ ions, the first hydration shell of Cu²⁺ is found to be labile, thus it shows both direct and indirect binding with the dsDNA, i.e., binding through displacement of water from the hydration shell or through the hydration shell. Though the binding propensity of Cu²⁺ ions with dsDNA is observed relatively stronger, the binding order to phosphates, major groove, and minor groove is found qualitatively similar (phosphates &gt; major groove &gt; minor groove) for both ions. The study gives a deep understanding of Cu²⁺ binding to DNA, which could be helpful in rationalizing the Cu²⁺ led ROS-mediated DNA damage.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107347"},"PeriodicalIF":3.3,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142567741","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":"Biophysical significance of fluorescence spectroscopy in deciphering nucleic acid dynamics: From fundamental to recent advancements","authors":"Vivek Pandey ,&nbsp;Tejasvi Pandey","doi":"10.1016/j.bpc.2024.107345","DOIUrl":"10.1016/j.bpc.2024.107345","url":null,"abstract":"<div><div>Fluorescence spectroscopy has revolutionized the study of nucleic acids, providing invaluable insights into the dynamic processes that underpin gene expression, replication, and repair. This review explores the application of fluorescence probes in monitoring the conformational changes, interactions, and regulatory mechanisms of DNA and RNA. We discuss the utility of intercalating and non-intercalating fluorescent probes in real-time tracking of nucleic acid dynamics, highlighting their role in elucidating the molecular mechanisms of DNA replication, transcriptional regulation, and DNA repair. By offering a detailed analysis of recent advancements, this review underscores the significance of fluorescence-based techniques in enhancing our understanding of nucleic acid behavior and their implications for genomic stability and therapeutic interventions.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107345"},"PeriodicalIF":3.3,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534624","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":"How fingers affect folding of a thumb: Inter-subdomain cooperation in the folding of SARS-CoV-2 RdRp protein","authors":"Anushree Sinha ,&nbsp;Angel Mary Chiramel Tony ,&nbsp;Susmita Roy","doi":"10.1016/j.bpc.2024.107342","DOIUrl":"10.1016/j.bpc.2024.107342","url":null,"abstract":"<div><div>The RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 is a critical enzyme essential for the virus's replication and transcription, making it a key therapeutic target. The RdRp protein exhibits a characteristic cupped right-hand shaped structure with two vital subdomains: the fingers and the thumb. Despite being distinct, biophysical experiments suggest that these subdomains cooperate to facilitate RNA accommodation, ensuring RdRp functionality. To investigate the structure-based mechanisms underlying the fingers-thumb interaction in both apo and RNA-bound RdRp, we constructed a coarse-grained structure-based model based on recent cryo-electron microscopy data. The simulations reveal frequent open-to-closed conformational transitions in apo RdRp, akin to a breathing-like motion. These conformational changes are regulated by the fingers-thumb association and the folding dynamics of the thumb subdomain. The thumb adopts a stable fold only when tethered by the fingers-thumb interface; when these subdomains are disconnected, the thumb transitions into an open state. A significant number of open-to-closed transition events were analyzed to generate a transition contact probability map, which highlights a few specific residues at the thumb-fingers interface, distant from the RNA accommodation sites, as essential for inducing the thumb's folding process. Given that thumb subdomain folding is critical for RNA binding and viral replication, the study proposes that these interfacial residues may function as remote regulatory switches and could be targeted for the development of allosteric drugs against SARS-CoV-2 and similar RNA viruses.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107342"},"PeriodicalIF":3.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534111","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":"In vitro and in silico effect of meldrum's acid-derived compounds on Staphylococcus aureus strains as NorA efflux pump inhibitors","authors":"Isaac Moura Araújo ,&nbsp;Raimundo Luiz Silva Pereira ,&nbsp;Ana Carolina Justino de Araújo ,&nbsp;Sheila Alves Gonçalves ,&nbsp;Saulo Relison Tintino ,&nbsp;Cícera Datiane de Morais Oliveira-Tintino ,&nbsp;Irwin Rose Alencar de Menezes ,&nbsp;Renata Salamoni ,&nbsp;Iêda Maria Begnini ,&nbsp;Ricardo Andrade Rebelo ,&nbsp;Luiz Everson da Silva ,&nbsp;Carolina Bandeira Domiciano ,&nbsp;Henrique Douglas Melo Coutinho","doi":"10.1016/j.bpc.2024.107344","DOIUrl":"10.1016/j.bpc.2024.107344","url":null,"abstract":"<div><div>The misuse of antibiotics has led to an alarming increase in bacterial strains resistant to these drugs. Efflux pumps, which expel antibiotics from bacterial cells, have emerged as one of the key mechanisms of bacterial resistance. In the quest to combat and mitigate bacterial resistance, researchers have turned their attention to efflux pump inhibitors as a potential solution. Meldrum's acid, a synthetic molecule widely utilized in the synthesis of bioactive compounds, has garnered significant interest in this regard. Hence, this study aims to investigate the antibacterial activity and evaluate the efficacy of three derivatives of meldrum's acid in inhibiting efflux mechanisms, employing both in silico and in vitro approaches. The antibacterial activity of the derivatives was assessed through rigorous broth microdilution testing. While the derivatives themselves did not exhibit direct antibacterial activity, they demonstrated remarkable potential in potentiating the effects of antibiotics. Additionally, fluorescence emission assays using ethidium bromide (EtBr) revealed fluorescence levels comparable to the positive control, indicating a possible blockade of efflux pumps. Molecular docking studies conducted in silico further supported these findings by revealing binding interactions similar to norfloxacin and CCCP, known efflux pump inhibitors. These results underscore the potential of meldrum's acid derivatives as effective inhibitors of efflux pumps. By inhibiting these mechanisms, the derivatives hold promise in enhancing the effectiveness of antibiotics and combatting bacterial resistance. This study contributes valuable insights into the development of novel strategies to address the pressing issue of bacterial resistance and paves the way for further research and exploration in this field.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107344"},"PeriodicalIF":3.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494593","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":"Solubilisation & purification of membrane proteins using benzylamine-modified SMA polymers","authors":"Aneel Akram ,&nbsp;Waled Hadasha ,&nbsp;Gestél C. Kuyler ,&nbsp;Michael-Phillip Smith ,&nbsp;Shauna Bailey-Dallaway ,&nbsp;Aiden Preedy ,&nbsp;Caolan Browne ,&nbsp;Luke Broadbent ,&nbsp;Adam Hill ,&nbsp;Tahreem Javaid ,&nbsp;Haroon Nazar ,&nbsp;Nikita Samra ,&nbsp;Anadil Naveed ,&nbsp;Holly Tregunna ,&nbsp;Hetal Joshi ,&nbsp;Nusheen Akhtar ,&nbsp;Aneesa Javed ,&nbsp;Jessica Bowater ,&nbsp;Joel Ravenhill ,&nbsp;Patrik Hajdu ,&nbsp;Alice J. Rothnie","doi":"10.1016/j.bpc.2024.107343","DOIUrl":"10.1016/j.bpc.2024.107343","url":null,"abstract":"<div><div>Extraction of proteins from the membrane using styrene maleic acid <em>co</em>-polymers (SMA), forming SMA lipid particles (SMALPs), has allowed for the first time the purification of membrane proteins with their lipid bilayer environment. To date, SMA2000 has been the most effective polymer used for this purpose, with a 2:1 ratio of styrene:maleic acid, and styrene and maleic acid moieties spread statistically throughout the chain. However, SMA2000 is a highly polydisperse polymer that contains an array of different polymer lengths and sequences. RAFT polymerisation offers much better control over the polymer length; however, homogeneous distribution of styrene and maleic acid throughout the polymer is difficult to achieve. Instead, here RAFT polymerisation was used to produce a 1:1 styrene:maleic anhydride polymer, which was then modified with benzylamine. This mimics the 2:1 hydrophobic:hydrophilic nature of SMA2000, while controlling the length and obtaining a homogeneous distribution of the hydrophobic moieties (styrene and <em>N</em>-benzylmaleimide). SMA-benzylamine (SMA-BA) polymers of three different lengths (2, 4, and 7 kDa) were all able to solubilise purified lipids, cellular membranes, and a range of specific proteins. However, the larger 7 kDa polymer solubilised membranes more slowly and less efficiently than the shorter polymers. This also affected the yield of purified protein obtained by affinity purification with this polymer. The smallest 2 kDa polymer solubilised membranes the fastest but appeared to offer less stability to the extracted proteins. The SMA-BA polymers were more sensitive to Mg²⁺ ions than SMA2000. SMA-BA 4 kDa was otherwise comparable to SMA2000 and even gave a higher degree of purity.</div></div>","PeriodicalId":8979,"journal":{"name":"Biophysical chemistry","volume":"316 ","pages":"Article 107343"},"PeriodicalIF":3.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142494594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}