an ab initio and density functional theory (dft) study about conformational analysis of tripeptide model hco−gly−l−ile−gly−nh2 is presented. the tripeptide was scanned about initial, central, and final residues, separately while for every scanning procedure the two other residues had been kept in the β conformation and side chain (sc) dihedral angles were maintained on the gauche− (g‾) state (χ...

We describe herein the synthesis of aziridine-containing amino acids embedded within tripeptide structures. A range of amine nucleophiles have been shown to open the aziridine amino acid regioselectively at the β-position under mild conditions and without the requirement for a catalyst, forming new adducts in the process. Amino acid N-termini (or an N-containing sidechain) also served as effect...

An enigma in the field of peptide transport is the structural basis for ligand promiscuity, as exemplified by PepT1, the mammalian plasma membrane peptide transporter. Here, we present crystal structures of di- and tripeptide-bound complexes of a bacterial homologue of PepT1, which reveal at least two mechanisms for peptide recognition that operate within a single, centrally located binding sit...

An ab initio and density functional theory (DFT) study about conformational analysis of tripeptide model HCO−GLY−L−ILE−GLY−NH2 is presented. The tripeptide was scanned about initial, central, and final residues, separately while for every scanning procedure the two other residues had been kept in the β conformation and side chain (SC) dihedral angles were maintained on the gauche− (g‾) state (χ...

The native-like structures of protonated glycine and peptide Gly3H+ were elucidated using cold ion IR spectroscopy these biomolecules hydrated by a controlled number water molecules. complexes generated directly from an aqueous solution gentle electrospray ionization. Already with single retained molecule, GlyH+ exhibits the structure characterized lack intramolecular hydrogen bonds. We use our...

This year marks the 50th anniversary of the coiled-coil triple helical structure of collagen, first proposed by Ramachandran's group from Madras. The structure is unique among the protein secondary structures in that it requires a very specific tripeptide sequence repeat, with glycine being mandatory at every third position and readily accommodates the imino acids proline/hydroxyproline, at the...