Chemistry and Physics of Lipids最新文献

{"title":"Interaction of chondroitin sulfate with zwitterionic lipid membranes","authors":"Grzegorz Łazarski,&nbsp;Natan Rajtar,&nbsp;Agata Żak,&nbsp;Dorota Jamróz,&nbsp;Mariusz Kepczynski","doi":"10.1016/j.chemphyslip.2024.105417","DOIUrl":"10.1016/j.chemphyslip.2024.105417","url":null,"abstract":"<div><p>Chondroitin sulfates (CSs) are important components of the extracellular matrix and side chains of membrane proteoglycans. These polysaccharides are, therefore, likely to interact with plasma membranes and play a significant role in modulating cellular functions. So far, the details of the processes occurring at the interface between the extracellular matrix and cellular membranes are not fully understood. In this study, we used experimental methods and atomic-scale molecular dynamics (MD) simulations to reveal the molecular picture of the interactions between CS and phosphocholine (PC) membranes, used as a simplified model of cell membranes. MD simulations reveal that the polysaccharide associates to the PC bilayer as a result of electrostatic interactions between the positively charged quaternary ammonium groups of choline and the negatively charged sulfate groups of CS. Compared to an aqueous medium, the adsorbed polysaccharide chains adopt more elongated conformations, which facilitates the electrostatic interactions with the membrane, and have a high degree of freedom to change their conformations and to adhere to and detach from the membrane surface. Penetrating slightly between the polar groups of the bilayer, they form a loosely anchored layer, but do not intrude into the hydrophobic region of the PC bilayer. The CS adsorption spread the PC headgroups apart, which is manifested by an increase in the value of the area pre lipid. The expansion of the lipid polar groups weakens the dispersion interactions between the lipid acyl chains. As a result, the lipid membrane in the membrane-polysaccharide contact areas becomes more fluid. Our outcomes may help to understand in detail the interaction of chondroitin sulfate with zwitterionic membranes at the molecular level, which is of biological interest since many biological processes depend on lipid-CS interactions.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0009308424000422/pdfft?md5=6c214d56ef7378c3385ccefcd230de0e&pid=1-s2.0-S0009308424000422-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141475559","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":"Structural characterization of cholesterol-rich nanoemulsion (LDE)","authors":"Aline S. Perez ,&nbsp;Aleksandra T. Morikawa ,&nbsp;Raul C. Maranhão ,&nbsp;Antônio M. Figueiredo Neto","doi":"10.1016/j.chemphyslip.2024.105418","DOIUrl":"10.1016/j.chemphyslip.2024.105418","url":null,"abstract":"<div><p>Cholesterol-rich nanoemulsion (LDE) can carry chemotherapeutic agents in the circulation and can concentrate those agents in the neoplastic and inflammatory tissues. This method improves the biodistribution of the drug and reduces toxicity. However, the structural stability of LDE particles, without or with associated drugs, has not been extensively investigated. The aim of the present study is to investigate the structural stability of LDE and LDE associated to paclitaxel, etoposide or methotrexate in aqueous solution over time by small-angle X-ray scattering (SAXS and Ultra SAXS) and dynamic light scattering (DLS). The results show that LDE and LDE associated with those chemotherapeutic agents had reproducible and stable particle diameter, physical structure, and aggregation behavior over 3-month observation period. As estimated from both DLS and Ultra-SAXS methods, performed at pre-established intervals, the average particle diameter of LDE alone was approx. 32 nm, of LDE-paclitaxel was 31 nm, of LDE-methotrexate was 35 nm and of LDE-etoposide was 36 nm. Ultra-SAXS analysis showed that LDE nanoparticles were quasi-spherical, and SAXS showed that drug molecules inside the particles showed a layered-like organization. Formulations of LDE with associated PTX, ETO or MTX were successfully tested in animal experiments and in patients with cancer or with cardiovascular disease, showing markedly low toxicity, good tolerability and possible superior pharmacological action. Our results may be useful for ensuing clinical trials of this novel Nanomedicine tool, by strengthening the knowledge of the structural aspects of those LDE formulations.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141464797","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":"Molecular insights into the interactions of theaflavin and epicatechin with different lipid bilayer membranes by molecular dynamics simulation","authors":"Rong-zu Nie ,&nbsp;Huo-min Luo ,&nbsp;Jing-yu Chen ,&nbsp;Li-heng Sun ,&nbsp;Zi-bo Wang ,&nbsp;Zhen-ping Zhang ,&nbsp;Ya-ru Bao","doi":"10.1016/j.chemphyslip.2024.105405","DOIUrl":"https://doi.org/10.1016/j.chemphyslip.2024.105405","url":null,"abstract":"<div><p>At present, consumers increasingly favored the natural food preservatives with fewer side-effects on health. The green tea catechins and black tea theaflavins attracted considerable interest, and their antibacterial effects were extensively reported in the literature. Epicatechin (EC), a green tea catechin without a gallate moiety, showed no bactericidal activity, whereas the theaflavin (TF), also lacking a gallate moiety, exhibited potent bactericidal activity, and the antibacterial effects of green tea catechins and black tea theaflavins were closely correlated with their abilities to disrupt the bacterial cell membrane. In our present study, the mechanisms of membrane interaction modes and behaviors of TF and EC were explored by molecular dynamics simulations. It was demonstrated that TF exhibited markedly stronger affinity for the POPG bilayer compared to EC. Additionally, the hydrophobic interactions of tropolone/catechol rings with the acyl chain part could significantly contribute to the penetration of TF into the POPG bilayer. It was also found that the resorcinol/pyran rings were the key functional groups in TF for forming hydrogen bonds with the POPG bilayer. We believed that the findings from our current study could offer useful insights to better understand the stronger antibacterial effects of TF compared to EC.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141090869","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":"Amantadine interactions with phase separated lipid membranes","authors":"Jacob J. Kinnun ,&nbsp;Jan Michael Y. Carrillo ,&nbsp;C. Patrick Collier ,&nbsp;Micholas Dean Smith ,&nbsp;John Katsaras","doi":"10.1016/j.chemphyslip.2024.105397","DOIUrl":"10.1016/j.chemphyslip.2024.105397","url":null,"abstract":"<div><p>Amantadine, a small amphilphic organic compound that consists of an adamantane backbone and an amino group, was first recognized as an antiviral in 1963 and received approval for prophylaxis against the type A influenza virus in 1976. Since then, it has also been used to treat Parkinson’s disease-related dyskinesia and is being considered as a treatment for corona viruses. Since amantadine usually targets membrane-bound proteins, its interactions with the membrane are also thought to be important. Biological membranes are now widely understood to be laterally heterogeneous and certain proteins are known to preferentially co-localize within specific lipid domains. Does amantadine, therefore, preferentially localize in certain lipid composition domains? To address this question, we studied amantadine’s interactions with phase separating membranes composed of cholesterol, DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine), POPC (1-palmitoyl-2-oleoyl-glycero-3-phosphocholine), and DOPC (1,2-dioleoyl-sn-glycero-3-phosphocholine), as well as single-phase DPhPC (1,2-diphytanoyl-sn-glycero-3-phos-phocholine) membranes. From Langmuir trough and differential scanning calorimetry (DSC) measurements, we determined, respectively, that amantadine preferentially binds to disordered lipids, such as POPC, and lowers the phase transition temperature of POPC/DSPC/cholesterol mixtures, implying that amantadine increases membrane disorder. Further, using droplet interface bilayers (DIBs), we observed that amantadine disrupts DPhPC membranes, consistent with its disordering properties. Finally, we carried out molecular dynamics (MD) simulations on POPC/DSPC/cholesterol membranes with varying amounts of amantadine. Consistent with experiment, MD simulations showed that amantadine prefers to associate with disordered POPC-rich domains, domain boundaries, and lipid glycerol backbones. Since different proteins co-localize with different lipid domains, our results have possible implications as to which classes of proteins may be better targets for amantadine.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140915426","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 impact of phospholipids with high transition temperature to enhance redox-sensitive liposomal doxorubicin efficacy in colon carcinoma model","authors":"Elaheh Mirhadi ,&nbsp;Anis Askarizadeh ,&nbsp;Leila Farhoudi ,&nbsp;Mohammad Mashreghi ,&nbsp;Saeed Behboodifar ,&nbsp;Seyedeh Hoda Alavizadeh ,&nbsp;Leila Arabi ,&nbsp;Mahmoud Reza Jaafari","doi":"10.1016/j.chemphyslip.2024.105396","DOIUrl":"https://doi.org/10.1016/j.chemphyslip.2024.105396","url":null,"abstract":"<div><p>In this study, we have developed a redox-sensitive (RS) liposomal doxorubicin formulation by incorporating 10,10′-diselanediylbis decanoic acid (DDA) organoselenium compound as the RS moiety. Hence, several RS liposomal formulations were prepared by using DOPE, HSPC, DDA, mPEG₂₀₀₀-DSPE, and cholesterol. <em>In situ</em> drug loading using a pH gradient and citrate complex yielded high drug to lipid ratio and encapsulation efficiency (100<!--> <!-->%) for RS liposomes. Liposomal formulations were characterized in terms of size, surface charge and morphology, drug loading, release properties, cell uptake and cytotoxicity, as well as therapeutic efficacy in BALB/c mice bearing C26 tumor cells. The formulations showed an average particle size of 200 nm with narrow size distributions (PDI &lt; 0.3), and negative surface charges varying from −6 mV to −18.6 mV. Our study confirms that the presence of the DDA compound in liposomes is highly sensitive to hydrogen peroxide at 0.1<!--> <!-->% w/v, resulting in a significant burst release of up to 40<!--> <!-->%. The <em>in vivo</em> therapeutic efficacy study in BALB/c mice bearing C26 colon carcinoma confirmed the promising function of RS liposomes in the tumor microenvironment which led to a prolonged median survival time (MST). The addition of hydrogenated soy phosphatidylcholine (HSPC) with a high transition temperature (Tm: 52–53.5<!--> <!-->°C) extended the MST of our 3-component formulation of F14 (DOPE/HSPC/DDA) to 60 days in comparison to Caelyx (PEGylated liposomal Dox), which is not RS-sensitive (39 days). Overall, HSPC liposomes bearing RS-sensitive moiety enhanced therapeutic efficacy against colon cancer <em>in vitro</em> and <em>in vivo</em>. This achievement unequivocally underscores the criticality of high-TM phospholipids, particularly HSPC, in significantly enhancing liposome stability within the bloodstream. In addition, RS liposomes enable the on-demand release of drugs, leveraging the redox environment of tumor cells, thereby augmenting the efficacy of the formulation.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140644349","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":"A convenient method for the relative and absolute quantification of lipid components in liposomes by 1H- and 31P NMR-spectroscopy","authors":"Andreas H. Franz,&nbsp;Nataliya M. Samoshina,&nbsp;Vyacheslav V. Samoshin","doi":"10.1016/j.chemphyslip.2024.105395","DOIUrl":"https://doi.org/10.1016/j.chemphyslip.2024.105395","url":null,"abstract":"<div><h3>Objective</h3><p>Liposomes are promising delivery systems for pharmaceutical applications and have been used in medicine in the recent past. Preparation of liposomes requires reliable characterization and quantification of the phospholipid components for which the traditional cumbersome molybdate method is used frequently. The objective was to improve relative and absolute quantification of lipid components from liposomes.</p></div><div><h3>Methods</h3><p>A reliable method for quantification of lipid composition in liposome formulations in the 1–10 μmol range with ¹H- and ³¹P NMR spectroscopy at 600 MHz has been developed. The method is based on three crystalline small-molecule standards (Ph₃PO₄, (Tol)₃PO₄, and Ph₃PO) in CDCl₃.</p></div><div><h3>Results</h3><p>Excellent calibration linearity and chemical stability of the standards was observed. The method was tested in blind fashion on liposomes containing POPC, PEG-ceramide and a pH-sensitive <em>trans</em>-aminocyclohexanol-based amphiphile (TACH).<span>¹</span> Relative quantification (percentage of components) as well as determination of absolute lipid amount was possible with excellent reproducibility with an average error of 5<!--> <!-->%. Quantification (triplicate) was accomplished in 15 min based on ¹H NMR and in 1 h based on ³¹P NMR. Very little change in mixture composition was observed over multiple preparative steps.</p></div><div><h3>Conclusion</h3><p>Liposome preparations containing POPC, POPE, DOPC, DPPC, TACH, and PEG-ceramide can be reliably characterized and quantified by ¹H NMR and ³¹P NMR spectroscopy at 600 MHz in the μmol range.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140554674","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":"Comparison of structural effects of cholesterol, lanosterol, and oxysterol on phospholipid (POPC) bilayers","authors":"Ayumi Okayama,&nbsp;Tatsuya Hoshino,&nbsp;Kohei Wada,&nbsp;Hiroshi Takahashi","doi":"10.1016/j.chemphyslip.2024.105376","DOIUrl":"10.1016/j.chemphyslip.2024.105376","url":null,"abstract":"<div><p>Membrane sterols contribute to the function of biomembranes by regulating the physical properties of the lipid bilayers. Cholesterol, a typical mammalian sterol, is biosynthesized by oxidation of lanosterol. From a molecular evolutionary perspective, lanosterol is considered the ancestral molecule of cholesterol. Here, we studied whether cholesterol is superior to lanosterol in regulating the physical properties of the lipid bilayer in terms of the structural effect on model biomembranes composed of a phospholipid. For comparison, oxysterol, which is formed by oxidation of cholesterol, was also studied. The phospholipid used was 1-palmitoyl-2-oleoyl-<em>sn</em>-glycero-3-phosphocholine (POPC), which is abundantly found in mammalian biomembranes, and 7β-hydroxycholesterol, which is highly cytotoxic, was used as the oxysterol. The apparent molecular volume was calculated from the mass density determined by the flotation method using H₂O and D₂O, and the bilayer thickness was determined by reconstructing the electron density distribution from X-ray diffraction data of the POPC/sterol mixtures at a sterol concentration of 30 mol%. The apparent occupied area at the bilayer surface was calculated from the above two structural data. The cholesterol system had the thickest bilayer thickness and the smallest occupied area of the three sterols studied here. This indicates that the POPC/cholesterol bilayer has a better barrier property than the other two systems. Compared to cholesterol, the effects of lanosterol and 7β-hydroxycholesterol on lipid bilayer properties can be interpreted as suboptimal for the function of mammalian biomembranes.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139688534","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":"Micelle formation of sodium taurolithocholate","authors":"Keisuke Matsuoka ,&nbsp;Rina Sekiguchi ,&nbsp;Tomokazu Yoshimura","doi":"10.1016/j.chemphyslip.2024.105378","DOIUrl":"10.1016/j.chemphyslip.2024.105378","url":null,"abstract":"<div><p>The proportion of sodium taurolithocholate (NaTLC) is extremely low in human bile salts. NaTLC forms aggregates with other lipids in the bile and functions as an emulsifying and solubilizing agent. The molecular structure of NaTLC contains hydrophilic hydroxyl and sulfonic acid groups at both ends of the steroid ring. This molecular structure is similar to bolaform amphiphilic substance having hydrophilic groups at both ends due to the characteristics of its molecular structure. This study investigated the aggregate properties of the NaTLC using surface tension measurements, light scattering, small-angle X-ray scattering (SAXS), and cryo-transmission electron microscopy (cryo-TEM). Surface tension measurement showed that the surface tension of the NaTLC solution decreased to 54 mN m⁻¹. The concentration that showed the minimum surface tension corresponded to the critical micelle concentration (CMC: 0.6 mmol L⁻¹, 308 K) determined by the change in light scattering intensity. On the other hand, the degree of counterion (sodium ions) binding to the micelles increased with increasing NaTLC concentration. SAXS and cryo-TEM measurements showed that the NaTLC formed large string-like micelles. The surface activity and large aggregates showed the potential for use as biosurfactants. However, because of the relatively low solubility of NaTLC in water, its use as a biosurfactant is limited to a narrow concentration range.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139688531","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":"Non-lamellar lyotropic liquid crystalline nanoparticles as nanocarriers for enhanced drug encapsulation of atorvastatin calcium and proanthocyanidins","authors":"Mardhiah Maslizan ,&nbsp;Muhammad Salahuddin Haris ,&nbsp;Mokrish Ajat ,&nbsp;Siti Nurul Ain Md Jamil ,&nbsp;Shah Christirani Azhar ,&nbsp;N. Idayu Zahid ,&nbsp;Intan Diana Mat Azmi","doi":"10.1016/j.chemphyslip.2024.105377","DOIUrl":"10.1016/j.chemphyslip.2024.105377","url":null,"abstract":"<div><p>Atorvastatin calcium (ATV) and proanthocyanidins (PAC) have a strong antioxidant activity, that can benefit to reduce the atherosclerotic plaque progression. Unfortunately, the bioavailability of ATV is greatly reduced due to its limited drug solubility while the PAC drug is unstable upon exposure to the atmospheric oxygen. Herein, the lyotropic liquid crystalline nanoparticles (LLCNPs) constructed by a binary mixture of soy phosphatidylcholine (SPC) and citric acid ester of monoglyceride (citrem) at different weight ratios were used to encapsulate the hydrophobic ATV and hydrophilic PAC. The LLCNPs were further characterized by small-angle X-ray scattering and dynamic light scattering. Depending on the lipid composition, the systems have a size range of 140–190 nm and were able to encapsulate both drugs in the range of 90–100%. Upon increasing the citrem content of drug-loaded LLCNPs, the hexosomes (H₂) was completely transformed to an emulsified inverse micellar (L₂). The optimum encapsulation efficiency (EE) of ATV and PAC were obtained in citrem/SPC weight ratio 4:1 (L₂) and 1:1 (H₂), respectively. There was a substantial change in the mean size and PDI of the nanoparticles upon 30 days of storage with the ATV-loaded LLCNPs exhibiting greater colloidal instability than PAC-loaded LLCNPs. The biphasic released pattern (burst released at the initial stage followed by the sustained released at the later stage) was perceived in ATV formulation, while the burst drug released pattern was observed in PAC formulations that could be attributed by its internal H₂ structure. Interestingly, the cytokine studies showed that the PAC-LLCNPs promisingly up regulate the expressions of tumor necrosis factor-alpha (TNF-α) better than the drug-free and ATV-loaded LLCNPs samples. The structural tunability of citrem/SPC nanoparticles and their effect on physicochemical characteristic, biological activities and potential as an alternative drug delivery platform in the treatment of atherosclerosis are discussed.</p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139688629","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":"Bottom-up approach to explore alpha-amylase assisted membrane remodelling","authors":"Harshit Kumar ,&nbsp;Sayar Mandal ,&nbsp;Reena Yadav ,&nbsp;Suhasi Gupta ,&nbsp;Hemraj Meena ,&nbsp;Mayur Kadu ,&nbsp;Rajni Kudawla ,&nbsp;Pratibha Sharma ,&nbsp;Indu Pal Kaur ,&nbsp;Subhabrata Maiti ,&nbsp;John H. Ipsen ,&nbsp;Tripta Bhatia","doi":"10.1016/j.chemphyslip.2023.105374","DOIUrl":"10.1016/j.chemphyslip.2023.105374","url":null,"abstract":"<div><p><span>Soluble alpha-amylases play an important role in the catabolism of polysaccharides. In this work, we show that the malt </span><em>α</em><span><span><span> -amylase can interact with the lipid membrane<span> and further alter its mechanical properties. Vesicle fluctuation spectroscopy is used for quantitative measurement<span> of the membrane bending rigidity of phosphatidylcholines </span></span></span>lipid vesicles from the shape fluctuation based on the whole contour of Giant </span>Unilamellar Vesicles<span> (GUVs). The bending rigidity of the 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine lipid vesicles in water increases significantly with the presence of 0.14 micromolar alpha-amylase (AA) in the exterior solution. It appears that the enzyme<span> present in the external solution interacts with the outer layer of the bilayer membrane, leading to an asymmetry of the solution on either side of the bilayer membrane and altering its elasticity. At AA concentration of 1.5 micromolars and above, changes in the morphology of the GUV membrane are observed. The interaction between AA in the external solution and the external leaflet causes the bilayer membrane to curve spontaneously, leading to the formation of outbuds, giving a positive spontaneous curvature of </span></span></span><em>C</em>₀ ≤ 0.05 <em>μ</em>m⁻¹<span> at ≈ 1 mg / ml of the AA concentration. We validate and characterize its concentration-dependent role in stabilizing the membrane curvature. Our findings indicate that the involvement of the enzyme, depending on the concentration, can have a considerable effect on the mechanical characteristics of the membrane.</span></p></div>","PeriodicalId":275,"journal":{"name":"Chemistry and Physics of Lipids","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139095368","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}