Peptides related to the active fragment of "proline rich polypeptide", an immunoregulatory protein of the ovine colostrum. Spectroscopic and computer modeling studies.
The preferred solution conformation of the PRP-hexapeptide (Tyr-Val-Pro-Leu-Phe-Pro) and of some of its structural analogues was investigated by NMR-spectroscopy, spectrofluorimetry and computer simulation technic. It was found that the preferred conformation is characterized by cis'-conformation of Pro3 and the gamma-turn on the Leu4-residue: for Val2 and Phe5 a beta-structure seems to be privileged. In such a conformation Val2 and Leu4 residues occupy exactly the same positions in space as residues i and i + 3 in an alpha-helix. It suggests that the PRP-hexapeptide can interact with receptor protein inducing or stabilizing its helical conformation by "knobs into holes" packing.
Siemion
I Z
IZ
Institute of Chemistry, Wroclaw University, Poland.
Folkers
G
G
Szewczuk
Z
Z
Jankowski
A
A
Kubik
A
A
Voelter
W
W
D000595:Amino Acid Sequence; D000818:Animals; D003126:Colostrum / Q000737:chemistry*; D005260:Female; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry* / Q000502:physiology; D011247:Pregnancy; D055232:Proline-Rich Protein Domains; D011487:Protein Conformation; D012756:Sheep
D010446:Peptide Fragments; D010455:Peptides