Search results for "Peptide"
showing 10 items of 4589 documents
Molluscan antimicrobial peptides, a review from activity-based evidences to computer-assisted sequences
2011
Antimicrobial peptides (AMPs) represent the most universal immune effectors. Molluscs constitute the second largest animal phylum, after Arthropods, in term of number of species. Only a negligible number has been investigated regarding AMPs. The choice of the species to be studied relied on their economical importance and availability. First studies on molluscan AMPs dated from 1996 and were based on biological activities of biochemical-purified fractions. Such approach released all the original structures we know, with biological activity sometimes different from one isoform to another. Then, molecular biology techniques were applied to molluscan AMPs starting in 1999. Complete screening o…
[60]Fullerene l -Amino Acids and Peptides: Synthesis under Phase-Transfer Catalysis Using a Phosphine–Borane Linker. Electrochemical Behavior
2017
International audience; A new method to link amino acid and peptide derivatives to [60]fullerene is described. It uses hydrophosphination with a secondary phosphine borane. First, the stereoselective synthesis of secondary phosphine borane amino acid derivatives was achieved by alkylation of phenylphosphine borane with gamma-iodo-alpha-amino ester reagents under phase transfer catalysis (PTC). Second, a sec-phosphine borane amino ester was saponified and coupled with alpha,gamma-diamino esters to afford the corresponding dipeptide derivatives in good yields. Finally, the hydrophosphination reaction of [60]fullerene by the sec-phosphine borane compounds was performed under PTC to obtain C-60…
Leki peptydowe przyszłością medycyny?
2022
To date, approximately 80 peptide drugs have been used practically. More than 150 peptides are in clinical development, and 400–600 peptides have been preclinically studied. Peptides act as hormones, growth factors, neurotransmitters, ion channel ligands, or antiinfective agents, therefore peptides are excellent candidates for drug discovery to complement medical treatment unmet by other types of medicines. For example, interfering peptides (IPs) have a high potential for modulation of protein-protein interaction (PPIs). Peptide drugs are used for bacterial and viral infections, problems with the circulatory system, diabetes, osteoporosis, appetite and hormone regulation, cancer, and many o…
Exploration of the sea urchin coelomic fluid via combinatorial peptide ligand libraries
2012
The urchin Paracentrotus lividus has been characterized via previous capture and enhancement of low-abundance proteins with combinatorial peptide ligand libraries (CPLL, ProteoMiner). Whereas in the control only 26 unique gene products could be identified, 82 species could be detected after CPLL treatment. Due to the overwhelming presence of two major proteins-the toposome (a highly glycosylated, modified calcium-binding, iron-less transferrin) and the major yolk proteins, belonging to the class of cell adhesion proteins-which constituted about 70% of the proteome of this biological fluid and strongly interfered with the capture of the minority proteome, no additional proteins could be dete…
Transport mechanism of peptides through supported liquid membranes
2007
The transport of selected dipeptides through supported liquid membranes impregnated with di(2-ethylhexyl) phosphoric acid in n-dihexyletherhas been investigated. The fluxes depend on the side chain of amino acids, presence in the peptide structure. The highest fluxes were obtainedfor the peptides extracted with the highest efficiency. It has been found that the hydrophobicity of investigated peptides, was not the major factor, influences their SLM permeation. In the conditions studied, it has been observed that the transport of peptide–carrier complex was depending on the acidic–basic properties of the analyte. The linearly least-square fittings of log { K 1 +[H + ]D } and log[(HR) 2 ] enable to…
Production and Characterization of Medium-Sized and Short Antioxidant Peptides from Soy Flour-Simulated Gastrointestinal Hydrolysate.
2021
Soybeans (Glycine max) are an excellent source of dietary proteins and peptides with potential biological activities, such as antihypertensive, anti-cholesterol, and antioxidant activity
Peroxisome Proliferator-Activated Receptors and Atherosclerosis
2011
The peroxisome proliferator-activated receptors (PPARs) represent the family of 3 nuclear receptor isoforms-PPARα, -γ, and -δ/β, which are encoded by different genes. As lipid sensors, they are primarily involved in regulation of lipid metabolism and subsequently in inflammation and atherosclerosis. Atherosclerosis considers accumulation of the cells and extracellular matrix in the vessel wall leading to the formation of atherosclerotic plaque, atherothrombosis, and other vascular complications. Besides existence of natural ligands for PPARs, their more potent synthetic ligands are fibrates and thiazolidindiones. Future investigations should now focus on the mechanisms of PPARs activation, …
Induction of body weight loss through RNAi-knockdown of APOBEC1 gene expression in transgenic rabbits
2014
In the search of new strategies to fight against obesity, we targeted a gene pathway involved in energy uptake. We have thus investigated the APOB mRNA editing protein (APOBEC1) gene pathway that is involved in fat absorption in the intestine. The APOB gene encodes two proteins, APOB100 and APOB48, via the editing of a single nucleotide in the APOB mRNA by the APOBEC1 enzyme. The APOB48 protein is mandatory for the synthesis of chylomicrons by intestinal cells to transport dietary lipids and cholesterol. We produced transgenic rabbits expressing permanently and ubiquitously a small hairpin RNA targeting the rabbit APOBEC1 mRNA. These rabbits exhibited a moderately but significantly reduced …
Extraction of peptides from body fluids using supported liquid membranes
2008
Sample pre-treatment is a very important step in many analytical procedures, especially when the analyte is presented in low concentration in complex sample matrices. In this paper, potential using of the supported liquid membrane (SLM) technique as a sample preparation step in order to isolate, pre-concentrate and separate small peptides and phosphono dipeptides from aqueous solutions and body fluids is discussed. An influence of various parameters including carrier type, donor and acceptor phase compositions, presence of salts and proteins in analysed samples on extraction efficiency and selectivity is presented. Additionally, comparison of SLM extraction efficiency from aqueous samples a…
Synthesis of Hybrid Tripeptide Peptidomimetics Containing Dehydroamino Acid and Aminophosphonic Acid in the Chain and Evaluation of Their Activity to…
2021
Synthesis of a new group of hybrid phosphonodehydropeptides composed of glycyl-(Z)-dehydrophenylalanine and structurally variable aminophosphonates alongside with investigations of their activity towards cathepsin C are presented. Obtained results suggest that the introduction of (Z)- dehydrophenylalanine residue into the short phosphonopeptide chain does induce the ordered conformation. Investigated peptides appeared to act as weak or moderate inhibitors of cathepsin C.