High magnetic field solid-state NMR was performed on amphipathic cationic antimicrobial peptides from fish to characterize their secondary structure and orientation in hydrated phospholipid bilayers. High-resolution distance and orientational restraints on 13C- and 15N-labeled amidated piscidins 1 and 3 provided site-specific information establishing alpha-helicity and an orientation parallel t...

Transpeptidase-catalyzed protein and peptide modifications have been widely utilized for generating conjugates of interest biological investigation or therapeutic applications. However, all known transpeptidases are constrained to ligating in the N-to-C orientation, limiting scope attainable products. Here, we report that an engineered asparaginyl ligase accepts diverse incoming nucleophile sub...

A 1.8-million-member D-octapeptide combinatorial library was constructed in which each member comprised a diversity-containing N-terminal pentapeptide and a C-terminal amidated triarginine motif. The C-terminal motif concentrated the library members at the fungal cell surface. A primary screen for inhibitors of Saccharomyces cerevisiae and Candida albicans growth, together with an in vitro seco...

We report the investigation of two 16-residue peptides in aqueous solution by means of molecular-dynamics simulations. The peptides constitute the C- and N-terminal halves of the 33-residue monomer whose dimer constitutes the leucine zipper of the yeast transcriptional activator, denoted GCN4-p1. To examine a hypothesis about coiled-coil formation, in which the C-terminal half contains a helix-...

The effects of hydrophobic thickness and the molar phosphatidylglycerol (PG) content of lipid bilayers on the structure and membrane interaction of three cationic antimicrobial peptides were examined: aurein 2.2, aurein 2.3 (almost identical to aurein 2.2, except for a point mutation at residue 13), and a carboxy C-terminal analog of aurein 2.3. Circular dichroism results indicated that all thr...

The effects of octadecylamide alginic acid (amidated alginate) and tetrahydrolipstatin on serum hepatic cholesterol, the faecal output fat sterols, were investigated in rats. Amidated alginate is a sorbent lipids, an inhibitor pancreatic lipase. Rats fed diets containing cholesterol palm at 10 70 g/kg, respectively. Palm was provided by coconut meal. 40 g/kg diet significantly decreased total l...

background: antimicrobial peptides with relative length (2-100 amino acids) and positive charge (pure charge (+9)-(+2)) are amphiphilic that isolated from a wide range of animals. recently, these peptides have been known as a part of innate immune response. nowadays, more than 500 antimicrobial peptides from animals have been reported. objectives: the aim of this study was to evaluate the anti-...

The tailed frog Ascaphus truei occupies a unique position in phylogeny as the most primitive extant anuran and is regarded as the sister taxon to the clade of all other living frogs. Eight structurally related peptides, termed ascaphins 1-8, were isolated from norepinephrine-stimulated skin secretions of A. truei and were shown to possess differential growth inhibitory activity against Escheric...