Structure and conformation of linear peptides. V. Structure of L-prolyl-glycyl-glycine.
The tripeptide, L-prolyl-glycyl-glycine, crystallizes in the trigonal space group P3(2), with a = b = 8.682(2) A, c = 12.008(2) and Z = 3. The structure was solved by direct methods and refined to an R-value of 0.07 for 727 reflections (I greater than 1.0 sigma). The molecule exists as a zwitterion in the crystal. The peptide units are trans and show significant deviations from planarity (omega 1 = 169.7 degrees, omega 2 = -170.1 degrees). The peptide backbone adopts a left-handed helical conformation similar to that of polyglycine II and polyproline II.
V
V
Lalitha
E
E
Subramanian
R
R
Parthasarathy
D000595:Amino Acid Sequence; D003460:Crystallization; D006860:Hydrogen Bonding; D009842:Oligopeptides; D010455:Peptides; D011487:Protein Conformation; D014961:X-Ray Diffraction
D009842:Oligopeptides; D010455:Peptides; C049251:prolyl-glycyl-glycine