The development of skin-care products is recently growing. Cosmetic formulas containing active ingredients with proven efficacy, namely cosmeceuticals, are based on various compounds, including peptides. Different whitening agents featuring anti-tyrosinase activity have been applied in the cosmeceutical field. Despite their availability, applicability often limited due to several drawbacks toxicity, lack stability, and other factors. In this work, we present inhibitory effect diphenolase...

Hydrophobic zinc(II) phthalocyanine-type derivatives, solubilized in polymeric micelles (PMs), provide a befitting group of so-called nanophotosensitizers, suitable for variety photodynamic therapy (PDT) protocols. The factors that influence the success such products PDT are location active cargo PMs and nanocarrier-enhanced ability to safely interact with biological systems fulfill their therapeutic functions. Therefore, aim this work was determine solubilization loci three phthalocyanines...

ABSTRACT Effective peptidomimetics should posses structural rigidity and appropriate interaction pattern leading to potential spatial electronic matching the target receptor site. Rational design of such small bioactive molecules could push chemical synthesis molecular modeling toward faster progress in medicinal chemistry. Conformational properties N‐t ‐butoxycarbonyl‐glycine‐( E/Z )‐dehydrophenylalanine N′,N ′‐dimethylamides (Boc‐Gly‐( )‐ΔPhe‐NMe 2 ) chloroform were studied by NMR IR...

The promotion of protein dimerization using the aggregation properties a ligand was explored and shown to produce complexes with unusual stoichiometries. Helical foldamer 2 synthesized bound human carbonic anhydrase (HCA) nanomolar active site ligand. Crystal structures show that hydrophobicity interactions its side chains lead formation an HCA2-23 complex in which three helices are stacked, two them being linked HCA molecule. middle stack can be replaced by alternate sequences 3 or 5....

Abstract The design of synthetic foldamers to selectively bind proteins is currently hindered by the limited availability molecular data establish key features recognition. Previous work has described dimerization human carbonic anhydrase II (HCA) through self‐association a quinoline oligoamide helical foldamer attached tightly binding HCA ligand. A crystal structure complex provided atomic details explain observed induction single helix handedness and revealed an unexpected...

Peptidotriazolamers are hybrid foldamers with features of peptides and triazolamers, containing alternation amide bonds 1,4-disubstituted 1H-1,2,3-triazoles conservation the amino acid side chains. We report on synthesis a new class peptidomimetics, in elucidation their conformational properties solution. Based enantiomerically pure propargylamines bearing stereogenic center propargylic position α-azido esters, building blocks were obtained by copper-catalyzed azide-alkyne cycloaddition....

Abstract Synthesis, structural and biological studies of pentapeptides containing two ΔPhe residues ( Z E isomers) in position 2 4 peptide chain were performed. All the investigated peptides adopted bent conformation majority them could exist as different conformers solution. Only pentapeptides, free N ‐termini appeared to act weak inhibitors cathepsin C with slow‐binding, competitive mechanism inhibition, acids being bound slightly better than their methyl esters. Results molecular modeling...

Tetrapeptide p-nitroanilides containing (E)-dehydrophenylalanine were synthesized and evaluated as inhibitors substrates of cathepsin C. Peptides a free, unblocked amino group appeared to be quite good the enzyme, whereas fully protected peptides acted very weak inhibitors. Structural studies by means NMR CD, alongside with molecular modelling, have proved that these are hydrolysed in one step direct removal p-nitroaniline from tetrapeptide.

Abstract Peptides conjugated with organic molecules can be useful tools for the development of novel bioactive compounds. The lysine side‐chain is an interesting functional group to act as a linker connect small in peptide conjugates. Herein we present design and synthesis four Safirinium derivatives, their facile conjugation solid phase, incorporation peptides. compounds differing functionalization nitrogen N2 condensed triazolyl moiety are building blocks conjugates perform...

Three‐dimensional structures of molecules traditionally assigned from nuclear Overhauser effects and vicinal coupling constants are recently complemented by measurements residual dipolar couplings. Residual couplings measured in a stretched poly(dimethylsiloxane) gel were used to determine the structure cyclolinopeptide A chloroform solution at −50 °C. After refinement, conformational details main cluster discussed relation crystal effect derived structures. Copyright © 2014 European Peptide...

Helically folded aromatic foldamers may constitute suitable candidates for the ab initio design of ligands protein surfaces. As preliminary steps toward exploration this hypothesis, a tethering approach was developed to detect interactions between and foldamer by confining former at surface latter. Cysteine mutants two therapeutically relevant enzymes, CypA IL4, were produced. Two series ten synthesized bearing different proteinogenic side chains either long or short linker functionalized...

The procedures for the synthesis of esters dehydropeptides containing C-terminal (Z)-dehydrophenylalanine and dehydroalanine have been elaborated. These appeared to be moderate or weak inhibitors cathepsin C, with some them exhibiting slow-binding behavior. As shown by molecular modeling, they are rather bound at surface enzyme not submersed in its binding cavities.

Structural studies of pentapeptides containing an achiral block, built from two dehydroamino acid residues (Δ(Z)Phe and ΔAla) glycines, as well one chiral L-Val residue were performed using NMR spectroscopy. The key role the in generation secondary structure peptides is discussed. obtained results suggest that strongest influence on conformation arises a valine inserted at C-terminal position. most ordered was found for peptide Boc-Gly-ΔAla-Gly-Δ(Z)Phe-Val-OMe (3), which adopts right-handed...

The increasing interest in peptidomimetics of biological relevance prompted us to synthesize a series cyclic peptides comprising trans-2-aminocyclohexane carboxylic acid (Achc) or trans-2-aminocyclopentane (Acpc). NMR experiments combination with MD calculations were performed investigate the three-dimensional structure peptides. These data compared conformational information obtained by electronic circular dichroism (ECD) and vibrational (VCD) spectroscopy. Experimental VCD spectra...

Abstract Conformational preferences of a group hexapeptides containing two dehydroamino acid residues in Positions 2 and 5 peptide chain were investigated by means spectroscopic methods (NMR CD) theoretical calculations. In the case dimethylsulfoxide (DMSO) solution, only with free N‐termini adopted rigid 3 10 ‐helical conformation, for rest examined peptides extended “zig‐zag” conformers predominant. CD measurements showed that chloroform solution conformational freedom was restricted. ©...

The development of peptide stapling techniques to stabilise α-helical secondary structure motifs peptides led the design modulators protein-protein interactions, which had been considered undruggable for a long time. We disclose novel approach towards utilising macrocyclisation by late-stage Suzuki-Miyaura cross-coupling bromotryptophan-containing catenin-binding domain axin. Optimisation linker length in order find compromise between both sufficient rigidity and flexibility resulted with an...

Antifreeze glycoproteins are a class of biological agents which enable living at temperatures below the freezing point body fluids. glycopeptides usually consist repeating tripeptide unit (-Ala-Ala-Thr*-), glycosylated threonine side chain. However, on microscopic level, mechanism action these compounds remains unclear. As previous research has shown, antifreeze activity strongly relies overall conformation molecule as well an stereochemistry amino acid residues. The desired monoglycosylated...

Biosurfactants are microbial surface active compounds which, contrary to synthetic surfactants, natural in origin, biodegradable and less toxic a human organism. For that reason, there is great research potential studies aimed at their purification, finding ways of utilization decreasing production costs. This paper demonstrates the process isolating purifying surfactin synthesized by Bacillus subtilis PCM 1949. Surfactin samples were prepared classical organic solvent extraction studied...