Solution conformation of CCK9, a cholecystokinin analog.
Cholecystokinin (CCK) is a peptide hormone endowed with several important biological activities, both in the central and peripheral nervous system. Previous conformational studies have dealt mainly with its C-terminal octapeptide fragment (CCK8), which represents the shortest fully circulating form of this hormone. We have undertaken a detailed NMR conformational study in a DMSOd6/H2O cryomixture at 278 K of the CCK analog H-Arg-Asp-Tyr(SO3H)-Thr-Gly-Trp-Nle-Asp-PheNH2 (CCK9) which retains all the bioactivities of CCK8, but was found to be remarkably more stable in acidic media and unaffected by air oxidation due to Met replacements. The predominant conformation contains a gamma-turn centered on Thr4, separated by Gly5 from a helical segment that comprises the C-terminal residues.
Moroder
L
L
MPI für Biochemie, Martinsried bei München, Germany.
D'Ursi
A
A
Picone
D
D
Amodeo
P
P
Temussi
P A
PA
D000595:Amino Acid Sequence; D002766:Cholecystokinin / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D018377:Neurotransmitter Agents / Q000737:chemistry; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012996:Solutions
D018377:Neurotransmitter Agents; D012996:Solutions; D002766:Cholecystokinin