RESUMEN

The spatial organization and conformational flexibility of neuropeptides of the gallatostatin family was studied by the method of theoretical conformational analysis. It was found that the spatial organization of neuropeptides allows the realization of folded helical structures of the C-terminal pentapeptide, and the flexibility of neuropeptides is due to a great number of low-energy states in the N-terminal fragment of the molecule.

Asunto(s)

Neuropéptidos/química , Secuencia de Aminoácidos , Enlace de Hidrógeno , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Termodinámica

RESUMEN

The structures and conformational peculiarities of five members of the callatostatin family of neuropeptides, i.e. Leu- and Met-callatostatins, ranging in size from 8 to 16 amino acid residues have been investigated by a theoretical conformational analysis method. A comparative analysis of the conformational flexibilities of Met-callatostatin with those of the hydroxylated analogues, [Hyp2]- and [Hyp3]-Met-callatostatin has been carried out. Helically packed C-terminal pentapeptide in the structure of all investigated Leu-callatostatins are shown to be possible. The reason for the great number low-energy conformers for the callatostatin N-terminus is discussed.

Asunto(s)

Neuropéptidos/química , Secuencia de Aminoácidos , Animales , Simulación por Computador , Modelos Moleculares , Datos de Secuencia Molecular , Oligopéptidos/química , Fragmentos de Péptidos/química , Conformación Proteica , Termodinámica