Quantifying Codon Usage in Signal Peptides: Gene Expression and Amino Acid Usage Explain Apparent Selection for Inefficient Codons
Publication date: Available online 19 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Alexander L. Cope, Robert L. Hettich, Michael A. GilchristAbstractThe Sec secretion pathway is found across all domains of life. A critical feature of Sec secreted proteins is the signal peptide, a short peptide with distinct physicochemical properties located at the N-terminus of the protein. Previous work indicates signal peptides are biased towards translationally inefficient codons, which is hypothesized to be an adaptation driven by selection to improve the efficacy and efficiency of the protein sec...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 20, 2018 Category: Biochemistry Source Type: research

Probing the effect of membrane contents on transmembrane protein-protein interaction using solution NMR and computer simulations
Publication date: Available online 18 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): P.E. Bragin, A.S. Kuznetsov, O.V. Bocharova, P.E. Volynsky, A.S. Arseniev, R.G. Efremov, K.S. MineevAbstractThe interaction between the secondary structure elements is the key process, determining the spatial structure and activity of a membrane protein. Transmembrane (TM) helix-helix interaction is known to be especially important for the function of so-called type I or bitopic membrane proteins. In the present work, we present the approach to study the helix-helix interaction in the TM domains of membr...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 19, 2018 Category: Biochemistry Source Type: research

Antimicrobial peptides from C-terminal amphipathic region of E. coli FtsA
Publication date: Available online 15 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Karabi Saikia, Nitin ChaudharyAbstractAntimicrobial peptides constitute an indispensable component of innate immune system in organisms ranging from bacteria to man. Despite this, peptides lag far behind the conventional antibiotics in treating infections. The menace of multidrug-resistant bacteria, however, has revived the antimicrobial peptide research. We reasoned that the membrane-binding regions of bacterial proteins could be purposed to combat them. Here, we identify potent antimicrobial peptides f...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 16, 2018 Category: Biochemistry Source Type: research

Intercellular communication via gap junction channels between chondrocytes and bone cells
In this study, we found for the first time that primary bone cells (BCs) including osteocytes, synovial cells (SCs) and chondrocytes (CHs) are able to establish cellular contacts and to couple through gap junction (GJ) channels with connexin43 (Cx43) being dominant. Transwell co-culture and identification by mass spectrometry revealed the exchange of essential amino acids, peptides and proteins including calnexin, calreticulin or CD44 antigen between contacting SCs, BCs and CHs. These results reveal that CHs, SCs and BCs are able to establish intercellular connections and to communicate through GJ channels, which provide a...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 15, 2018 Category: Biochemistry Source Type: research

Trypanosoma brucei aquaglyceroporins mediate the transport of metabolic end-products: Methylglyoxal, D-lactate, L-lactate and acetate
Publication date: Available online 12 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Néstor L. Uzcátegui, Katherine Figarella, Andrea Segnini, Sabrina Marsiccobetre, Florian Lang, Eric Beitz, Alexis Rodríguez-Acosta, Adam BertlAbstractBloodstream forms of Trypanosoma (T.) brucei, the causative agent of African sleeping sickness, possess a highly active glycolysis, which generates as main end-products: pyruvate under aerobic conditions, and pyruvate and glycerol under anaerobic conditions. To secrete them into the extracellular milieu, the parasites have at least two ...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 12, 2018 Category: Biochemistry Source Type: research

Editorial Board
Publication date: October 2018Source: Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1860, Issue 10Author(s): (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 12, 2018 Category: Biochemistry Source Type: research

Preface to Emergence of Complex Behavior in Biomembranes
Publication date: October 2018Source: Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1860, Issue 10Author(s): Marjorie L. Longo (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 12, 2018 Category: Biochemistry Source Type: research

Molecular details on the intermediate states of melittin action on a cell membrane
Publication date: Available online 10 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Jiaojiao Liu, Shufeng Xiao, Jingliang Li, Bing Yuan, Kai Yang, Yuqiang MaAbstractAntimicrobial peptides (AMPs) provide a promising solution to the serious threat of multidrug-resistant bacteria or superbugs to public healthcare, due to their unique disruption to bacterial membrane such as perforation. Unfortunately, the underlying action mechanism of AMPs, especially the possible transition between the membrane binding and perforation states of peptides (i.e., the classical two-state model), is still lar...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 11, 2018 Category: Biochemistry Source Type: research

Corrigendum to “The YhhN protein of Legionella pneumophila is a Lysoplasmalogenase” [Biochim. Biophys. Acta, Biomembr. 1848 (2) (2015) 742–751]
Publication date: Available online 8 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Marianne S. Jurkowitz, Aalapi Patel, Lai-Chu Wu, Annalise Krautwater, Douglas R. Pfeiffer, Charles E. Bell (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 9, 2018 Category: Biochemistry Source Type: research

Cholesterol and phosphatidylserine are engaged in adenoviral dodecahedron endocytosis
Publication date: Available online 7 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Marta Jedynak, Remigiusz Worch, Małgorzata Podsiadła-Białoskórska, Jadwiga Chroboczek, Ewa SzołajskaAbstractAdenoviral dodecahedron is a virus-like particle composed of twelve penton base proteins, derived from the capsid of human adenovirus type 3. Due to the high cell penetration capacity, it was used as a vector for protein, peptide and drug delivery. Two receptors are known to be involved in the endocytic dodecahedron uptake, namely αv integrins and heparan sulfate proteoglycans. Sinc...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 8, 2018 Category: Biochemistry Source Type: research

A DIE responsive NIR-fluorescent cell membrane probe
This study adds new and important findings to recent developments of DIE responsive probes and further applications of this controllable emission-switching event are anticipated.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 8, 2018 Category: Biochemistry Source Type: research

Short arginine-rich lipopeptides: From self-assembly to antimicrobial activity
Publication date: Available online 7 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Emilia Sikorska, Oktawian Stachurski, Damian Neubauer, Izabela Małuch, Dariusz Wyrzykowski, Marta Bauer, Krzysztof Brzozowski, Wojciech KamyszAbstractIn this paper, we examine antimicrobial and cytotoxic activities, self-assembly and interactions with anionic and zwitterionic membranes of short arginine-rich lipopeptides: C16-RRRR-NH2, C14-RRRR-NH2, C12-RRRR-NH2, and C16-PRRR-NH2. They show a tendency to self-assembly into micelles over a millimolar concentration range, but it is not required for antimic...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 7, 2018 Category: Biochemistry Source Type: research

Lipid bilayer position and orientation of novel carprofens, modulators of γ-secretase in Alzheimer's disease
Publication date: Available online 7 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Evgeniy Salnikov, Binia Drung, Gabin Fabre, Anna Itkin, Michal Otyepka, Norbert A. Dencher, Boris Schmidt, Thomas Hauß, Patrick Trouillas, Burkhard BechingerAbstractγ-Secretase is an integral membrane protein complex and is involved in the cleavage of the amyloid precursor protein APP to produce amyloid-β peptides. Amyloid-β peptides are considered causative agents for Alzheimer's disease and drugs targeted to γ-secretase are investigated as therapeutic treatments. We synthesiz...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 7, 2018 Category: Biochemistry Source Type: research

The oligomeric plasticity of Hsp20 of Sulfolobus acidocaldarius protects environment-induced protein aggregation and membrane destabilization
Publication date: Available online 7 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Mousam Roy, Sayandeep Gupta, Somi Patranabis, Abhrajyoti GhoshAbstractSmall heat shock proteins (sHsps) are a ubiquitous family of molecular chaperones that rescue misfolded proteins from irreversible aggregation during cellular stress. Many such sHsps exist as large polydisperse species in solution, and a rapid dynamic subunit exchange between oligomeric and dissociated forms modulates their function under a variety of stress conditions. Here, we investigated the structural and functional properties of H...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 7, 2018 Category: Biochemistry Source Type: research

Elementary processes of antimicrobial peptide PGLa-induced pore formation in lipid bilayers
Publication date: Available online 3 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Farliza Parvez, Jahangir Md. Alam, Hideo Dohra, Masahito YamazakiAbstractAntimicrobial peptide PGLa induces the leakage of intracellular content, leading to its bactericidal activity. However, the elementary process of PGLa-induced leakage remains poorly understood. Here, we examined the interaction of PGLa with lipid bilayers using the single giant unilamellar vesicle (GUV) method. We found that PGLa induced membrane permeation of calcein from GUVs comprised of dioleoylphosphatidylcholine (DOPC) and diol...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 3, 2018 Category: Biochemistry Source Type: research

The homologous Arabidopsis MRS2/MGT/CorA-type Mg2+ channels, AtMRS2-10 and AtMRS2-1 exhibit different aluminum transport activity
Publication date: Available online 31 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Sumio Ishijima, Yuri Manabe, Yuri Shinkawa, Ayumi Hotta, Akino Tokumasu, Moe Ida, Ikuko SagamiAbstractMagnesium (Mg2+) plays a critical role in many physiological processes. The AtMRS2/MGT family, which consists of nine Arabidopsis genes (and two pseudo-genes) belongs to a eukaryotic subset of the CorA superfamily of divalent cation transporters. AtMRS2-10 and AtMRS2-1 possess the signature GlyMetAsn sequence conserved in the CorA superfamily; however, they have low sequence conservation with CorA. Direct m...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 1, 2018 Category: Biochemistry Source Type: research

Expression of voltage-gated calcium channels augments cell susceptibility to membrane disruption by nanosecond pulsed electric field
Publication date: Available online 1 September 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Kiril Hristov, Uma Mangalanathan, Maura Casciola, Olga N. Pakhomova, Andrei G. PakhomovAbstractWe compared membrane permeabilization by nanosecond pulsed electric field (nsPEF) in HEK293 cells with and without assembled CaV1.3 L-type voltage-gated calcium channel (VGCC). Individual cells were subjected to one 300-ns pulse at 0 (sham exposure); 1.4; 1.8; or 2.3 kV/cm, and membrane permeabilization was evaluated by measuring whole-cell currents and by optical monitoring of cytosolic Ca2+. nsPEF had either...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - September 1, 2018 Category: Biochemistry Source Type: research

Effect of polyols on the DMPC lipid monolayers and bilayers
In this study, the effect of polyols, erythritol, xylitol, mannitol, on a model membrane systems composed of DMPC was investigated using differential scanning calorimetry and Fourier transform infrared spectroscopy. Generally, it is considered that polyols possess strong hydrophilic properties, and either does not interact with the hydrophobic environment at all, or these interactions are very weak. To better understand the mutual interactions between polyols and the lipid system, the Langmuir technique was used to examine the molecular organization of monolayers and to calculate their thickness in the presence of polyols ...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 30, 2018 Category: Biochemistry Source Type: research

Are the short cationic lipopeptides bacterial membrane disruptors? Structure-Activity Relationship and molecular dynamic evaluation
Publication date: Available online 25 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Katarzyna E. Greber, Joanna Zielińska, Łukasz Nierzwicki, Krzesimir Ciura, Piotr Kawczak, Joanna Nowakowska, Tomasz Bączek, Wiesław SawickiAbstractShort cationic lipopeptides are amphiphilic molecules that exhibit antimicrobial activity mainly against Gram-positives. These compounds bind to bacterial membranes and disrupt their integrity. Here we examine the structure-activity relation (SAR) of lysine-based lipopeptides, with a prospect to rationally design more active compounds. The presented study aim...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 25, 2018 Category: Biochemistry Source Type: research

Effect of late endosomal DOBMP lipid and traditional model lipids of electrophysiology on the anthrax toxin channel activity
Publication date: Available online 23 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Nnanya Kalu, Yoav Atsmon-Raz, Sanaz Momben Abolfath, Laura Lucas, Clare Kenney, Stephen H. Leppla, D. Peter Tieleman, Ekaterina M. NestorovichAbstractAnthrax toxin action requires triggering of natural endocytic transport mechanisms whereby the binding component of the toxin forms channels (PA63) within endosomal limiting and intraluminal vesicle membranes to deliver the toxin's enzymatic components into the cytosol. Membrane lipid composition varies at different stages of anthrax toxin internalization, wit...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 24, 2018 Category: Biochemistry Source Type: research

Biophysical characterization and antitumor activity of synthetic Pantinin peptides from scorpion's venom
In this study, we have explored the in vitro antitumor activity of antimicrobial pantinin peptides against the tumor cell lines MDA-MB-231 (breast adenocarcinoma) and DU − 145 (prostate adenocarcinoma) and healthy fibroblasts HGF − 1. To further improve our mechanistic understanding for this class of compounds, we have also performed a biophysical characterization of these peptides in lipid model membranes. Cell viability assays revealed that all peptides were more effective on tumor cells when compared to fibroblasts, indicating selectivity towards cancer cells. Furthermore, flow cytometry analysis rev...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 23, 2018 Category: Biochemistry Source Type: research

Modeling squid axon Na+ channel by a nucleation and growth kinetic mechanism
Publication date: Available online 23 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Rolando Guidelli, Lucia BecucciAbstractA kinetic model accounting for all salient features of the Na+ channel of the squid giant axon is provided. The model furnishes explanations for the Cole-Moore-like effect, the rising phase of the ON gating current and the slow ‘intermediate component’ of its decaying phase, as well as the gating charge immobilization. Experimental ON ionic currents are semi-quantitatively simulated by the use of only three free parameters, upon assuming that the Na+ channe...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 23, 2018 Category: Biochemistry Source Type: research

Cell surface proteoglycan-mediated uptake and accumulation of the Alzheimer's disease peptide Aβ(1–42)
Publication date: Available online 23 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Emelie Wesén, Audrey Gallud, Alexandra Paul, David J. Lindberg, Per Malmberg, Elin K. EsbjörnerAbstractProteoglycans (PGs) have been found in Alzheimer's disease amyloid-β (Aβ) plaques and their glycosaminoglycan chains reportedly influence Aβ aggregation, neurotoxicity and intracellular accumulation in cell and animal models, but their exact pathophysiological role(s) remain unclear. We have studied the cellular uptake of fluorescently labelled Aβ(1–42) and Aβ(1&n...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 23, 2018 Category: Biochemistry Source Type: research

Fine-tuning of the stability of β-strands by Y181 in perfringolysin O directs the prepore to pore transition
Publication date: Available online 21 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Magdalena Kulma, Aleksandra Kacprzyk-Stokowiec, Gabriela Traczyk, Katarzyna Kwiatkowska, Michał DadlezAbstractPerfringolysin O (PFO) is a toxic protein that forms β-barrel transmembrane pores upon binding to cholesterol-containing membranes. The formation of lytic pores requires conformational changes in PFO that lead to the conversion of water-soluble monomers into membrane-bound oligomers. Although the general outline of stepwise pore formation has been established, the underlying mechanistic detail...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 21, 2018 Category: Biochemistry Source Type: research

Calcium enhances binding of Clostridium perfringens epsilon toxin to sulfatide
In conclusion, the present work highlights the role of sulfatide as an important element in the pathophysiology of Etx and reveals the influence of calcium in the interaction of Etx, but not of proEtx, with the target membrane.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 16, 2018 Category: Biochemistry Source Type: research

Thermodynamics and kinetics of joint action of antiviral agent tilorone and DMSO on model lipid membranes
Publication date: Available online 15 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): N.A. Kasian, O.V. Vashchenko, L.V. Budianska, R.Ye. Brodskii, L.N. LisetskiAbstractIndividual and joint action of two water-soluble drugs, DMSO and tilorone, on model l-α-dipalmitoylphosphatidylcholine (DPPC) membranes were studied in equilibrium and kinetic regimes by differential scanning calorimetry (DSC). For equilibrium experiments, the drugs were introduced during preparation of the model membrane. In kinetic studies, one of the drugs was added to the DPPC membrane already containing the other d...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 15, 2018 Category: Biochemistry Source Type: research

The use of styrene-maleic acid copolymer (SMA) for studies on T cell membrane rafts
We examined this approach for studies on several types of T cell membrane proteins, previously defined as raft or non-raft associated, to see whether the properties of the raft derived SMALPs differ from non-raft SMALPs. Our results indicate that two types of raft proteins, GPI-anchored proteins and two Src family kinases, are markedly present in membrane fragments much larger (>250 nm) than those containing non-raft proteins (
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 14, 2018 Category: Biochemistry Source Type: research

Electrophysiological characterization of Tityus obscurus β toxin 1 (To1) on Na+-channel isoforms
Publication date: Available online 14 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Diogo Vieira Tibery, Leandro Ambrósio Campos, Caroline Barbosa Farias Mourão, Steve Peigneur, Andréa Cruz e Carvalho, Jan Tytgat, Elisabeth Ferroni SchwartzAbstractTo1, previously named Tc49b, is a peptide neurotoxin isolated from venom of the scorpion Tityus obscurus that is responsible for lethal human poisoning cases in the Brazilian Amazonian region. Previously, To1 was shown to be lethal to mice and to change Na+ permeation in cerebellum granular neurons from rat brain. In addition...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 14, 2018 Category: Biochemistry Source Type: research

Investigating the interaction of Grammostola rosea venom peptides and model lipid bilayers with solid-state NMR and electron microscopy techniques
Publication date: Available online 12 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Geraldine Polido, Xiangyan Shi, Dian Xu, Chengchen Guo, Rich Thai, Joseph P. Patterson, Nathan C. Gianneschi, Thomas M. Suchyna, Frederick Sachs, Gregory P. HollandAbstractSpider venom contains a number of small peptides that can control the gating properties of a wide range of ion channels with high affinity and specificity. These ion channels are responsible for coordination and control of many bodily functions such as transducing signals into sensory functions, smooth muscle contractions as well as servi...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 12, 2018 Category: Biochemistry Source Type: research

Membrane order and ionic strength modulation of the inhibition of the membrane-bound acetylcholinesterase by epigallocatechin‑3‑gallate
Publication date: Available online 11 August 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Paula B. Salazar, Fernando G. Dupuy, Alejandro de Athayde Moncorvo Collado, Carlos J. MinahkAbstractIn the present work, we analyzed how external factors can modulate the efficiency of epigallocatechin‑3‑O‑gallate (EGCG) inhibition of a membrane-bound isoform of the acetylcholinesterase. Increasing the ionic strength but not the osmolarity of the bulk medium proved to be an important factor. In addition, we verified a clear correlation between the inhibitory activity with the order degree of the membr...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 11, 2018 Category: Biochemistry Source Type: research

Fast and potent bactericidal membrane lytic activity of PaDBS1R1, a novel cationic antimicrobial peptide
This study reveals that PaDBS1R1 has potential application in antibiotic therapy.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 10, 2018 Category: Biochemistry Source Type: research

Editorial Board
Publication date: September 2018Source: Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1860, Issue 9Author(s): (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - August 9, 2018 Category: Biochemistry Source Type: research

Diverse residues of intracellular loop 5 of the Na+/H+ exchanger modulate proton sensing, expression, activity and targeting
In this study, we characterized the structure and function of intracellular loop 5 (IL5), specifically amino acids 431–443. Mutation of eleven residues to alanine caused partial or nearly complete inhibition of transport; notably, mutation of residues L432, T433, I436, N437, R440 and K443 demonstrated these residues had critical roles in NHE1 function independent of effects on targeting or expression. The nuclear magnetic resonance (NMR) solution spectra of the IL5 peptide in a membrane mimetic sodium dodecyl sulfate solution revealed that IL5 has a stable three-dimensional structure with substantial alpha helical ch...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 31, 2018 Category: Biochemistry Source Type: research

Cholesterol and phosphatidylethanolamine lipids exert opposite effects on membrane modulations caused by the M2 amphipathic helix
Publication date: Available online 30 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Jianjun Pan, Annalisa Dalzini, Likai SongAbstractMembrane curvature remodeling induced by amphipathic helices (AHs) is essential in many biological processes. Here we studied a model amphipathic peptide, M2AH, derived from influenza A M2. We are interested in how M2AH may promote membrane curvature by altering membrane physical properties. We used atomic force microscopy (AFM) to examine changes in membrane topographic and mechanical properties. We used electron paramagnetic resonance (EPR) spectroscopy to ex...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 31, 2018 Category: Biochemistry Source Type: research

Electrostatic state of the cytoplasmic domain influences inactivation at the selectivity filter of the KcsA potassium channel
Publication date: Available online 25 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Minako Hirano, Toru IdeAbstractKcsA is a proton-activated K+ channel that is regulated at two gates: an activation gate located in the inner entrance of the pore and an inactivation gate at the selectivity filter. Previously, we revealed that the cytoplasmic domain (CPD) of KcsA senses proton and that electrostatic changes of the CPD influences the opening and closing of the activation gate. However, our previous studies did not reveal the effect of CPD on the inactivation gate because we used a non-inactivat...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 25, 2018 Category: Biochemistry Source Type: research

Theonellamide A, a marine-sponge-derived bicyclic peptide, binds to cholesterol in aqueous DMSO: Solution NMR-based analysis of peptide-sterol interactions using hydroxylated sterol
In this study, we utilized 1H NMR chemical shift changes (Δδ1H) in aqueous DMSO solution to evaluate the TNM-A/sterol interaction. Because Chol does not dissolve well in this solvent, we used 25-hydroxycholesterol (25-HC) instead, which turned out to interact with membrane-bound TNM-A in a very similar way to that of Chol. We determined the dissociation constant, KD, by NMR titration experiments and measured the chemical shift changes of TNM-A induced by 25-HC binding in the DMSO solution. Significant changes were observed for several amino acid residues in a certain area of the molecule. The results from the s...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 25, 2018 Category: Biochemistry Source Type: research

The effects of oxidised phospholipids and cholesterol on the biophysical properties of POPC bilayers
Publication date: Available online 25 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Alexandra Schumann-Gillett, Megan L. O'MaraAbstractOxidation of unsaturated membrane phospholipids by oxidative stress is associated with inflammation, infection, numerous diseases and neurodegenerative disorders. Lipid oxidation is observed in experimental samples when the parent lipid is exposed to oxidative stressors. The effect of phospholipid oxidation on the properties of biological membranes are still being explored, while low concentrations (0.1–2.0 mol%) of oxidised phospholipids are associat...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 25, 2018 Category: Biochemistry Source Type: research

Revealing cardiolipins influence in the construction of a significant mitochondrial membrane model
Publication date: Available online 21 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): S.C. Lopes, G. Ivanova, B. de Castro, P. GameiroAbstractCardiolipins are essential for the integrity and the dynamics of the mitochondria membrane, where they exclusively exist in eukaryotes. Changes in cardiolipins membrane levels have been related to several cardiac health disorders. To evaluate cardiolipins impact on membrane properties a physico-chemical study was conducted using steady-state fluorescence anisotropy, dynamic light scattering and Nuclear Magnetic Resonance (1H and 31P NMR). Different binar...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 21, 2018 Category: Biochemistry Source Type: research

Polysialic acid chains exhibit enhanced affinity for ordered regions of membranes
Publication date: Available online 21 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Karolina Sapoń, Teresa Janas, Aleksander F. Sikorski, Tadeusz JanasAbstractPolysialic acid (polySia) forms linear chains which are usually attached to the external surface of the plasma membrane mainly through the Neural Cell Adhesion Molecule (NCAM) protein. It is exposed on neural cells, several types of cancer cells, dendritic cells, and egg and sperm cells. There are several lipid raft-related phenomena in which polySia is involved; however the mechanisms of polySia action as well as determinants of its ...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 21, 2018 Category: Biochemistry Source Type: research

Morphological changes induced in erythrocyte by amyloid beta peptide and glucose depletion: A combined atomic force microscopy and biochemical study
Publication date: Available online 21 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Cristiana Carelli-Alinovi, Simone Dinarelli, Beatrice Sampaolese, Francesco Misiti, Marco GirasoleAbstractCirculating red blood cells (RBCs) undergo aging, a fundamental physiological phenomenon that regulates their turnover. We show that treatment with beta amyloid peptide 1–42 (Aβ) accelerates the occurrence of morphological and biochemical aging markers in human RBCs and influences the cell metabolism leading to intracellular ATP depletion. The morphological pattern has been monitored using Atom...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 21, 2018 Category: Biochemistry Source Type: research

Crossover from picosecond collective to single particle dynamics defines the mechanism of lateral lipid diffusion
Publication date: Available online 20 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Dima Bolmatov, Yong Q. Cai, Dmitry Zav’yalov, Mikhail ZhernenkovAbstractIt has been widely accepted that the thermally excited motions of the molecules in a cell membrane is the prerequisite for the cell to carry its biological functions. On the other hand, the detailed mapping of the ultrafast picosecond single-molecule and the collective lipid dynamics in a cell membrane remains rather elusive. Here, we report all-atom molecular dynamics simulations of a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bil...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 20, 2018 Category: Biochemistry Source Type: research

Purification and reconstitution of polyspecific H+/organic cation antiporter human MATE1
Publication date: Available online 17 July 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Tatsuya Kawasaki, Takuya Matsumoto, Yuma Iwai, Mamiyo Kawakami, Narinobu Juge, Hiroshi Omote, Tomohiro Nabekura, Yoshinori MoriyamaAbstractHuman MATE1 (multidrug and toxin extrusion 1, hMATE1) is a H+/organic cation (OC) exchanger responsible for the final step of toxic organic cation excretion in the kidney and liver. To investigate the mechanism of transport, we have established an in vitro assay procedure that includes its expression in insect cells, solubilization with octyl glucoside, purification, and r...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 18, 2018 Category: Biochemistry Source Type: research

How to minimize dye-induced perturbations while studying biomembrane structure and dynamics: PEG linkers as a rational alternative
The objective was to compare, on equal footing, the relative strengths and weaknesses of acyl chain labeling, headgroup labeling, and labeling based on poly-ethyl-glycol (PEG) linkers in determining biomembrane properties. We observed that the most appropriate strategy to minimize dye-induced membrane perturbations and to allow consideration of Brownian-like diffusion in liquid-ordered membrane environments is to decouple the dye from a membrane by a PEG linker attached to a lipid headgroup. Yet, while the use of PEG linkers may sound a rational and even an obvious approach to explore membrane dynamics, the results also su...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 18, 2018 Category: Biochemistry Source Type: research

Cerium oxide nanoparticles as potential antibiotic adjuvant. Effects of CeO2 nanoparticles on bacterial outer membrane permeability
ConclusionsCeO2 NPs increases the effectiveness of antimicrobials which activity is compromised by drug resistance mechanisms. The synergistic effect is the result of the interaction of NPs with the bacterial outer membrane. The low toxicity of CeO2 NPs makes them attractive as antibiotic adjuvants against MDR pathogens.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 18, 2018 Category: Biochemistry Source Type: research

Simulations of simple Bovine and Homo sapiens outer cortex ocular lens membrane models with a majority concentration of cholesterol
This article is part of a Special Issue entitled: Emergence of Complex Behavior in Biomembranes edited by Marjorie Longo.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research

Serum albumin impedes the amyloid aggregation and hemolysis of human islet amyloid polypeptide and alpha synuclein
This study offers a new insight on the native inhibition of amyloidosis.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research

Trace amounts of pyroglutaminated Aβ-(3–42) enhance aggregation of Aβ-(1–42) on neuronal membranes at physiological concentrations: FCS analysis of cell surface
This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research

Molecular simulation aspects of amyloid peptides at membrane interface
This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy. (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research

Fluorescence imaging of the interaction of amyloid beta 40 peptides with live cells and model membrane
This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.Graphical abstract (Source: Biochimica et Biophysica Acta (BBA) Biomembranes)
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research

Electrostatic and hydrophobic interactions of lipid-associated α-synuclein: The role of a water-limited interfaces in amyloid fibrillation
Publication date: Available online 8 February 2018Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Tae Su Choi, Jong Yoon Han, Chae Eun Heo, Sun Woo Lee, Hugh I. KimAbstractHuman α‑synuclein (αSyn) is an intrinsically disordered protein (IDP) whose biological and pathological functions in brain neuronal cells have not yet been fully elucidated. αSyn intrinsically participates in aiding neurotransmitter trafficking through αSyn the association with lipid membranes. However, lipid-associated states of αSyn also induce amyloid self-assembly that is linked to the pathogenesis...
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - July 11, 2018 Category: Biochemistry Source Type: research