In a polypeptide chain, a cis-to-trans rearrangement of two consecutive proline residues can be achieved by rotating the: (1) O angle to 10° (2) w angle to 180° (3) Ψ angle to 0° (4) x angle to 60° In a polypeptide chain, cis-to-trans isomerization primarily involves rotation around the peptide bond (ω angle). ω (omega) … Read more
The measured values of main chain torsion angles of a residue in a polypeptide has values (Φ=+50, Ψ=+60). What type of secondary structure is it most likely to be present in?
(1) Left-handed a-helix
(2) Right-handed a-helix
(3) Type II ẞ-turn
(4) Parallel B-sheet
In peptides the values of dihedral angle phi (D) is based on rotation around (1) N-Ca bond (2) Ca -C’ bond (3) C’-N bond (4) N-H bond The phi (φ) angle in peptides is defined as the dihedral angle around the N–Cα bond. This angle is measured between the plane formed by the C’ (of … Read more