title: Harnessing D-amino acids for peptide motif designs. Synthesis and solution conformation of Boc-D-Glu-Ala-Gly-Lys-NHMe and Boc-L-Glu-Ala-Gly-Lys-NHMe.
abstract: In examining the use of D-amino acids in designing specific peptide folding motifs, the tetrapeptide Boc-D-Glu-Ala-Gly-Lys-NHMe 1 and its analog 2 featuring L-Glu were synthesized for a comparison of their solution conformations by NMR spectroscopy. The temperature coefficients of amide proton resonances, NOE data, side-chain CH2 anisotropies and salt titration results suggest a weak type II reverse-turn conformation for peptide 2, and a tandem II' turn-3(10)-helix conformation of appreciable conformational stability for peptide 1 in apolar solvents. The latter is of potential interest as the N-terminal helix cap that could support the design of longer 3(10) helices. Possible origins of appreciable difference in the conformational stabilities of the diastereomers are discussed.
authors.affiliation: Biotechnology Centre, Indian Institute of Technology, Powai, Bombay.
authors.forename: V
authors.initials: V
authors.lastname: Bobde
authors.forename: Y U
authors.initials: YU
authors.lastname: Sasidhar
authors.forename: S
authors.initials: S
authors.lastname: Durani
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry*; D004355:Drug Stability; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding; D012680:Sensitivity and Specificity; D012996:Solutions; D013237:Stereoisomerism; D013696:Temperature
chemical_list: D000596:Amino Acids; D010455:Peptides; D012996:Solutions