title: Conformation propensities of des-acyl-ghrelin as probed by CD and NMR.
abstract: Des-acyl-ghrelin is a 28 amino acid peptide secreted by both human and rat stomach. Together with ghrelin and obestatin, it is obtained by post-translational modification of a 117 aminoacid prepropeptide mainly expressed in distinct endocrine cell type in the stomach. Although its receptor has not been unambiguously identified so far, des-acyl-ghrelin is considered one of the strongest antagonists of ghrelin in activating the growth hormone secretagogue receptor (GHS-R). Here the secondary structure of des-acyl-ghrelin in different experimental conditions has been investigated and compared with that of obestatin, a bioactive peptide having similar biological functions. CD and NMR techniques have been combined for gaining the desired conformational features. The obtained structures support a steady alpha-helix structure spanning residues from 7 to 14, very similar to that observed for obestatin at the same experimental conditions, leading to suggest that a similar secondary structure can be associated with the similar biological role.
authors.affiliation: Department of Biotechnology, University of Siena, Via A. Moro 2, 53100 Siena, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: De Ricco
authors.forename: Daniela
authors.initials: D
authors.lastname: Valensin
authors.forename: Elena
authors.initials: E
authors.lastname: Gaggelli
authors.forename: Gianni
authors.initials: G
authors.lastname: Valensin
mesh_terms: D002942:Circular Dichroism; D054439:Ghrelin / Q000737:chemistry*; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D015335:Molecular Probes / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation
chemical_list: D054439:Ghrelin; D015335:Molecular Probes; C422650:ghrelin, des-n-octanoyl