Search results for "PEPTIDE"
showing 10 items of 4589 documents
Increasing concentration of polyunsaturated fatty acids in browning boreal lakes is driven by nuisance algaGonyostomum
2020
Elevated concentrations of dissolved organic carbon (DOC) promote browning of lakes, which alters the physicochemical properties of water and ecosystem functioning. However, browning‐induced changes in basal production of polyunsaturated fatty acids from the n‐3 and n‐6 families (n‐3 and n‐6 PUFA) in lakes are not fully understood. The concentrations of PUFA, which are micronutrients required to maintain growth and reproduction of consumers, have been suggested to either rise or decline in seston as a response to lake browning. Elevated DOC concentrations may also promote bacterial biomass and production and thus potentially increase the concentration of bacterial fatty acids (BAFA) in sest…
Best Practices in Constant pH MD Simulations: Accuracy and Sampling
2022
Various approaches have been proposed to include the effect of pH in molecular dynamics (MD) simulations. Among these, the λ-dynamics approach proposed by Brooks and co-workers [Kong, X.; Brooks III, C. L. J. Chem. Phys.1996, 105, 2414−2423] can be performed with little computational overhead and hfor each typeence be used to routinely perform MD simulations at microsecond time scales, as shown in the accompanying paper [Aho, N. et al. J. Chem. Theory Comput.2022, DOI: 10.1021/acs.jctc.2c00516]. At such time scales, however, the accuracy of the molecular mechanics force field and the parametrization becomes critical. Here, we address these issues and provide the community with guidelines on…
High Lipid Content of Prey Fish and n−3 PUFA Peroxidation Impair the Thiamine Status of Feeding-Migrating Atlantic Salmon (Salmo salar) and Is Reflec…
2022
Signs of impaired thiamine (vitamin B1) status in feeding-migrating Atlantic salmon (Salmo salar) were studied in three Baltic Sea areas, which differ in the proportion and nutritional composition of prey fish sprat (Sprattus sprattus) and herring (Clupea harengus). The concentration of n−3 polyunsaturated fatty acids (n−3 PUFAs) increased in salmon with dietary lipids and n−3 PUFAs, and the hepatic peroxidation product malondialdehyde (MDA) concentration increased exponentially with increasing n−3 PUFA and docosahexaenoic acid (DHA, 22:6n−3) concentration, whereas hepatic total thiamine concentration, a sensitive indicator of thiamine status, decreased with th…
Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculoviru…
2015
Antimicrobial peptides (AMPs) and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae…
Low cholesterol stimulates the nonamyloidogenic pathway by its effect on the α-secretase ADAM 10
2001
Biochemical, epidemiological, and genetic findings demonstrate a link between cholesterol levels, processing of the amyloid precursor protein (APP), and Alzheimer's disease. In the present report, we identify the α-secretase ADAM 10 ( a d isintegrin a nd m etalloprotease) as a major target of the cholesterol effects on APP metabolism. Treatment of various peripheral and neural cell lines with either the cholesterol-extracting agent methyl-β-cyclodextrin or the hydroxymethyl glutaryl-CoA reductase inhibitor lovastatin resulted in a drastic increase of secreted α-secretase cleaved soluble APP. This strong stimulatory effect was in the range obtained with phorbol esters and was further increa…
Data from: Ergosterol biosynthesis: a fungal pathway for life on land?
2012
Sterols, essential lipids of most eukaryotic cells, ensure important structural and signaling functions. The selection pressure which has led to different dominant sterols in the three eukaryotic kingdoms remains unknown. Here we investigated the influence of the progression in the different steps of the ergosterol biosynthetic pathway (EBP) on the yeast resistance to transitions from aqueous to aerial media, typical perturbations of the higher fungi habitats. Five mutants of the EBP (ergΔ), accumulating different sterol intermediates in the EBP, and the WT strain were exposed to drying under atmospheric air or nitrogen and wetting. Results show that the progression in the EBP parallels an …
Analysis of complement C3 activation products in human atherosclerotic lesions.
1991
Abstract Cleavage of the complement C3 protein is essential for complement activation. Saline extracts of human atherosclerotic lesions were examined by various techniques for the presence of C3 cleavage fragments. Crossed intermediate gel immunoelectrophoresis revealed that native C3 was the predominate C3 protein in extracts and that the C3dg fragment was also detected. SDS-PAGE/ Western blot analyses of lesion extracts employing monoclonal antibodies directed at C3c and C3dg fragment determinants demonstrated molecular weight bands corresponding to the known molecular weights of all the physiologic C3 cleavage fragments, except Cab which is known to have a short half-life. After C3, the …
Paracentrin 1, a synthetic antimicrobial peptide from the sea-urchin Paracentrotus lividus, interferes with staphylococcal and Pseudomonas aeruginosa…
2014
The rise of antibiotic-resistance as well as the reduction of investments by pharmaceutical companies in the development of new antibiotics have stimulated the investigation for alternative strategies to conventional antibiotics. Many antimicrobial peptides show a high specificity for prokaryotes and a low toxicity for eukaryotic cells and, due to their mode of action the development of resistance is considered unlikely. We recently characterized an antimicrobial peptide that was called Paracentrin 1 from the 5-kDa peptide fraction from the coelomocyte cytosol of the Paracentrotus lividus. In this study, the chemically synthesized Paracentrin 1, was tested for its antimicrobial and antibiof…
Modular Solid-Phase Synthesis of Antiprotozoal Barnesin Derivatives
2020
Here, we applied and optimized a solid support (SP)-based Horner-Wadsworth-Emmons reagent to prepare SP-bound vinylogous amino acids. Subsequent SP-based peptide synthesis, global deprotection, and chemical modifications yielded 14 lipodipeptides carrying vinylogous amino acids, including the natural product barnesin A (1). Biological evaluation revealed that several synthesized derivatives show micromolar to nanomolar inhibitory activity against papain-like cysteine proteases, human cathepsin L, and rhodesain.
Anti-phospholipase A2 and anti-inflammatory activity of Santolina chamaecyparissus
2000
The activity of the Santolina chamaecyparissus methanol extract was tested against the phospholipase A2 (PLA2)-induced mouse paw edema and in vitro inhibition of PLA2 activity. After fractionation, only the dichloromethane extract was active against the PLA2 in vitro test. In addition, it reduced the edema induced by arachidonic acid, and by 12-O-tetradecanoylphorbol-13-acetate in a multidose test. After chromatography on silicagel and gel filtration on Sephadex, and using an in vitro anti-PLA2 assay-guided process, we have isolated and identified from the dichloromethane extract the flavone nepetin and four sesquiterpenes.