Read by QxMD icon Read

surfactant peptide

Siham Akmoussi-Toumi, Souad Khemili-Talbi, Imen Ferioune, Salima Kebbouche-Gana
The present study investigates the purification and biochemical characterization of an extracellular lipase (HML) from Haloarchaea Haloferax mediterranei strain ATS1, isolated from the Sebkha (Medea, Algeria). The pure protein was obtained with ammonium sulfate precipitation (40-70%)-dialysis and UNO Q-6 FPLC, and characterized biochemically. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis revealed that the purified enzyme was a monomer, with a molecular mass of 45,011...
May 15, 2018: International Journal of Biological Macromolecules
Lyné van Rensburg, Johann M van Zyl, Johan Smith
Background: Previous studies in our laboratory demonstrated that a synthetic peptide containing lung surfactant enhances the permeability of chemical compounds through bronchial epithelium. The purpose of this study was to test two formulations of Synsurf® combined with linezolid as respirable compounds using a pressurized metered dose inhaler (pMDI). Methods: Aerosolization efficiency of the surfactant-drug microparticles onto Calu-3 monolayers as an air interface culture was analyzed using a Next Generation Impactor™...
2018: Drug Design, Development and Therapy
Valeria Castelletto, Ruth H Barnes, Kimon-Andreas Karatzas, Charlotte J C Edwards-Gayle, Francesca Greco, Ian W Hamley, Robert Rambo, Jani Seitsonen, Janne Ruokolainen
The activity of antimicrobial peptides stems from their interaction with bacterial membranes, which are disrupted according to a number of proposed mechanisms. Here, we investigate the interaction of a model antimicrobial peptide that contains a single arginine residue with vesicles containing model lipid membranes. The surfactant-like peptide Ala6-Arg (A6R) is studied in the form where both termini are capped (CONH-A6R-NH2, capA6R) or uncapped (NH2-A6R-OH, A6R). Lipid membranes are selected to correspond to model anionic membranes (POPE/POPG) resembling those in bacteria or model zwitterionic membranes (POPC/DOPC) similar to those found in mammalian cells...
May 8, 2018: Biomacromolecules
Shixin Fa, Yan Zhao
Peptides rich in basic residues such as lysine and arginine play important roles in biology such as bacterial defense and cell penetration. Although peptide-binding materials with high sequence-specificity have broad potential applications, the diverse functionalities of peptide side chains make their molecular recognition extremely difficult. By covalently capturing micelles of a doubly cross-linkable surfactant with solubilized peptide templates, we prepared water-soluble molecularly imprinted nanoparticles with high sequence-specificity for basic peptides...
November 14, 2017: Chemistry of Materials: a Publication of the American Chemical Society
Marta Benigni, Silvia Pescina, Maria Aurora Grimaudo, Cristina Padula, Patrizia Santi, Sara Nicoli
Psoriasis is a widespread chronic disease affecting 2-4% of the population in Western countries. Its mild-to-moderate form, representing approximately 80% of the total cases, is treated by topical application, with corticosteroid being the standard treatment. However, in case of psoriasis, no single treatment works for every patient and optimizing topical therapy is a key aspect. A possible alternative is represented by cyclosporine, an immunosuppressant cyclic peptide administered orally in the treatment of the severe form...
April 23, 2018: International Journal of Pharmaceutics
Yan Zhao
Sequence-selective recognition of peptides in water has been one of the most important and yet unsolved problems in bioorganic and supramolecular chemistry. The motivation comes from not only the importance of these molecules in biology but also the fundamental challenges involved in the research. Molecular imprinting in doubly cross-linked surfactant micelles offers a unique solution to this problem by creating a "supramolecular code" on the micelle surface that matches the structural features of the peptide chain...
April 25, 2018: Chemistry: a European Journal
Anna Jasińska, Aleksandra Góralczyk, Adrian Soboń, Jerzy Długoński
The aim of this study was to overproduce, identify and apply novel laccase-like multicopper oxidases (LMCOs) from Myrothecium roridum in a dye removal process. LMCOs' production was enhanced by modifying the medium and adding copper ions. After purification, two proteins, LMCO1 and LMCO2, with molecular masses of 46.7 and 66.3 kDa were discovered. Peptide analysis by mass spectrometry revealed that they belong to the cupredoxin superfamily. Characteristic peptide sequences were obtained for MCOs and bilirubin oxidases...
April 25, 2018: Acta Biochimica Polonica
L M P Souza, J B Nascimento, A L Romeu, E D Estrada-López, A S Pimentel
Molecular dynamics simulations were successfully performed to understand the absorption mechanism of antimicrobial peptides LL-37, CATH-2, and SMAP-29 in a lung surfactant model. The antimicrobial peptides quickly penetrate in the lung surfactant model in dozens or hundreds nanoseconds, but they electrostatically interact with the lipid polar heads during the simulation time of 2 μs. This electrostatic interaction should be the explanation for the inactivation of the antimicrobial peptides when co-administrated with lung surfactant...
April 19, 2018: Colloids and Surfaces. B, Biointerfaces
Nicklas Österlund, Yashraj S Kulkarni, Agata D Misiaszek, Cecilia Wallin, Dennis M Krüger, Qinghua Liao, Farshid Mashayekhy Rad, Jüri Jarvet, Birgit Strodel, Sebastian K T S Wärmländer, Leopold L Ilag, Shina C L Kamerlin, Astrid Gräslund
The amphiphilic nature of the amyloid-β (Aβ) peptide associated with Alzheimer's disease facilitates various interactions with biomolecules such as lipids and proteins, with effects on both structure and toxicity of the peptide. Here, we investigate these peptide-amphiphile interactions by experimental and computational studies of Aβ(1-40) in the presence of surfactants with varying physico-chemical properties. Our findings indicate that electrostatic peptide-surfactant interactions are required for co-clustering and structure induction in the peptide and that the strength of the interaction depends on the surfactant net charge...
April 23, 2018: ACS Chemical Neuroscience
Yejiao Shi, Ran Lin, Honggang Cui, Helena S Azevedo
Peptide amphiphiles (PAs), consisting of a hydrophobic alkyl chain covalently bound to a hydrophilic peptide sequence, possess a versatile molecular design due to their combined self-assembling features of amphiphile surfactants and biological functionalities of peptides. Through rational design, PAs can self-assemble into a variety of nanostructures with controlled shape, size, and biological functionality to deliver therapeutic and imaging agents to target cells. Here, we describe principles to design multifunctional PAs for self-assembly into micellar nanostructures and targeted intracellular delivery...
2018: Methods in Molecular Biology
Grazia Licciardello, Andrea Caruso, Patrizia Bella, Rodolpho Gheleri, Cinzia P Strano, Alice Anzalone, Emmanouil A Trantas, Panagiotis F Sarris, Nalvo F Almeida, Vittoria Catara
Cyclic lipopeptides (CLPs) are considered as some of the most important secondary metabolites in different plant-associated bacteria, thanks to their antimicrobial, cytotoxic, and surfactant properties. In this study, our aim was to investigate the role of the Quorum Sensing (QS) system, PcoI/PcoR, and the LuxR-type transcriptional regulator RfiA in CLP production in the phytopatogenic bacterium, Pseudomonas corrugata based on our previous work where we reported that the pcoR and rfiA mutants were devoid of the CLPs cormycin and corpeptin production...
2018: Frontiers in Microbiology
Rianne Bartelds, Mohammad Hadi Nematollahi, Tjeerd Pols, Marc C A Stuart, Abbas Pardakhty, Gholamreza Asadikaram, Bert Poolman
Niosomes are used in studies for drug delivery or gene transfer. However, their physical properties and features relative to liposomes are not well documented. To characterize and more rationally optimize niosome formulations, the properties of these vesicle systems are compared to those of liposomes composed of phosphatidylcholine and phosphatidylethanolamine lipids plus cholesterol. Niosomes are highly stable and only slightly more leaky than liposomes as assayed by calcein leakage; the permeability for ions (KCl) is higher than that of liposomes...
2018: PloS One
William S Kish, Matthew K Roach, Hiroyuki Sachi, Amith D Naik, Stefano Menegatti, Ruben G Carbonell
Prior work described the identification and characterization of erythropoietin-binding cyclic peptides SLFFLH, VVFFVH, FSLLHH and FSLLSH (all of the form cyclo[(Nα -Ac)Dap(A)-X1 -X6 -AE], wherein X1 -X6 is the listed sequences). In this work, the peptide ligands were synthesized on Toyopearl chromatographic resins and utilized for purifying recombinant human erythropoietin (rHuEPO) from complex sources. Elution buffer pH and composition were optimized to maximize the recovery of standard rHuEPO from the peptide resins...
March 27, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Elise Azar, Doru Constantin, Dror E Warschawski
We study the local effect of the antimicrobial peptide Gramicidin A on bilayers composed of lipids or surfactants using nuclear magnetic resonance spectroscopy and wide-angle X-ray scattering, techniques that probe the orientational and positional order of the alkyl chains, respectively. The two types of order vary with temperature and peptide concentration in complex ways which depend on the membrane composition, highlighting the subtlety of the interaction between inclusions and the host bilayer. The amplitude of the variation is relatively low, indicating that the macroscopic constants used to describe the elasticity of the bilayer are unlikely to change with the addition of peptide...
March 28, 2018: European Physical Journal. E, Soft Matter
Yi Wang, Lele Zhou, Qi Kang, Li Yu
Trypsin plays a central role in catalyzing the hydrolysis of peptide bonds, so a technique with simple operation is needed to monitor the activity of trypsin. Here a simple and label-free senor based on liquid crystals (LCs) was developed by employing bovine serum albumin (BSA) as the enzyme substrate and dodecyl trimethyl ammonium bromide (DTAB) as the controller for the alignment of LC. It was found that DTAB could form a self-assembled monolayer at the aqueous/LC interface to produce the dark optical images of LCs...
June 1, 2018: Talanta
Jeness Campodonico, Massimo Mapelli, Emanuele Spadafora, Stefania Ghilardi, Piergiuseppe Agostoni, Cristina Banfi, Susanna Sciomer
Alveolar-capillary membrane evaluated by carbon monoxide diffusion (DLCO) plays an important role in heart failure (HF). Surfactant Proteins (SPs) have also been suggested as a worthwhile marker. In HF, Levosimendan improves pulmonary hemodynamics and reduces lung fluids but associated SPs and DLCO changes are unknown. Sixty-five advanced HF patients underwent spirometry, cardiopulmonary exercise test (CPET) and SPs determination before and after Levosimendan. Levosimendan caused natriuretic peptide-B (BNP) reduction, peakVO2 increase and VE/VCO2 slope reduction...
March 13, 2018: Respiratory Physiology & Neurobiology
Niloy Kundu, Debasis Banik, Nilmoni Sarkar
Amphiphiles are class of molecules which are known to assemble into a variety of nanostructures. The understanding and applications of self-assembled systems are based on what has been learned from biology. Among the vast number of self-assemblies, in this article, we have described the formation, characterization and dynamics of two important biologically inspired assemblies, vesicles and fibrils. Vesicles, which can be classified into several categories depending on the sizes and components, are of great interest due to their potential application in drug delivery and as nanoscale reactor...
March 15, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Noriho Sakamoto, Hiroshi Ishimoto, Tomoyuki Kakugawa, Minoru Satoh, Tomoko Hasegawa, Shin Tanaka, Atsuko Hara, Shota Nakashima, Hirokazu Yura, Takuto Miyamura, Hanako Koyama, Towako Morita, Seiko Nakamichi, Yasushi Obase, Yuji Ishimatsu, Hiroshi Mukae
BACKGROUND: Interstitial lung disease (ILD) is a prognostic indicator of poor outcome in myositis. Although the pathogenesis of myositis-associated ILD is not well understood, neutrophils are thought to play a pivotal role. Neutrophils store azurophil granules that contain defensins, which are antimicrobial peptides that regulate the inflammatory response. Here, we evaluated levels of the human neutrophil peptides (HNPs) α-defensin 1 through 3 in patients with myositis-associated ILD to determine whether HNPs represent disease markers and play a role in the pathogenesis of myositis-associated ILD...
March 12, 2018: BMC Pulmonary Medicine
Dipendra Gyawali, Jimin P Kim, Jian Yang
A novel photo-crosslinkable nanogel is prepared from a biodegradable polymer template with intrinsic photoluminescence and high photostability. The fluorescent nanogels display excellent biodegradability and cytocompatibility owed to the facile synthesis scheme involving a solvent-and surfactant-free one-pot reaction, derived entirely from biocompatible monomers citric acid, maleic acid, L-cysteine, and poly(ethylene glycol). The resultant nanogels are less than 200 nm in diameter with a narrow size distribution and monodispersity, and demonstrate long-term structural stability in biological buffer for two weeks...
March 2018: Bioactive Materials
Lucía Martínez-Jothar, Sofia Doulkeridou, Raymond M Schiffelers, Javier Sastre Torano, Sabrina Oliveira, Cornelus F van Nostrum, Wim E Hennink
Maleimide-thiol chemistry is widely used for the design and preparation of ligand-decorated drug delivery systems such as poly(lactide-co-glycolide) (PLGA) based nanoparticles (NPs). While many publications on nanocarriers functionalized exploiting this strategy are available in the literature, the conditions at which this reaction takes place vary among publications. This paper presents a comprehensive study on the conjugation of the peptide cRGDfK and the nanobody 11A4 (both containing a free thiol group) to maleimide functionalized PLGA NPs by means of the maleimide-thiol click reaction...
March 9, 2018: Journal of Controlled Release: Official Journal of the Controlled Release Society
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"