New peptidomimetics containing a β2,2-isoxazoline amino acid, 5-(aminomethyl)-3-phenyl-4,5-dihydroisoxazole-5-carboxylic acid (Isox-β2,2AA), were prepared and studied by NMR theoretical calculations. Interestingly, inserting R-Isox-β2,2AA in short tri- hexapeptide models, an unexpected α-turn-like motif was observed, thanks to unprecedented strong H-bond involving C=N of isoxazoline side chain ...

The mechanisms that protect mammalian cells against amino acid deprivation are only partially understood. We found that during an acute decrease in external amino acid supply, before up-regulation of the autophagosomal-lysosomal pathway, efficient translation was ensured by proteasomal protein degradation. Amino acids for the synthesis of new proteins were supplied by the degradation of preexis...

Introduction: Meteoritic amino acid abundances and abundance ratios have been diversely applied in cosmochemistry. Abundances have gauged the duration of experimental heating of Murchison [1], and abundance ratios have exhibited differences according to meteorite classification group and the extent of asteroidal parent body aqueous and thermal alteration [25]. Enantiomeric excesses (ees), expre...

In this study, a series of dipeptide compounds were synthesized as result the reaction Fmoc group-protected amino acids and chalcones with triazine reagent. The structures characterized by FT-IR, 1H 13C APT NMR spectroscopy techniques. electrical behavior conjugares was investigated an impedance analyzer in frequency range 1-30 kHz. variation dielectric constant, loss, susceptibility parameters...

Many commonly used force fields for protein systems such as AMBER, CHARMM, GROMACS, OPLS, and ECEPP have amino-acid-independent force-field parameters for main-chain torsion-energy terms. Here, we propose a new type of amino-acid-dependent torsion-energy terms in the force fields. As an example, we applied this approach to AMBER ff03 force field and determined new amino-acid-dependent parameter...