Targeting integrins: insights into structure and activity of cyclic RGD pentapeptide mimics containing azabicycloalkane amino acids.
Bioorg Med Chem
; 14(1): 169-80, 2006 Jan 01.
Article
en En
| MEDLINE
| ID: mdl-16214345
ABSTRACT
A small library of cyclic RGD pentapeptide mimics incorporating stereoisomeric 5,6- and 5,7-fused bicyclic lactams was synthesized. This library was found to contain high-affinity ligands for the alpha(v)beta3 integrin. The aim of this study was to investigate activity, selectivity, and structure of these ligands in order to identify new specific alpha(v)-integrin antagonists that could be evaluated as tumor angiogenesis inhibitors. In vitro screening, including receptor-binding assays to purified alpha(v)beta3, alpha(v)beta5, and alpha5beta1 integrins, and platelet aggregation assay, revealed ST1646 as a potent, highly selective alpha(v)beta3/alpha(v)beta5 integrin antagonist. Structure determination of the cyclic RGD pentapeptide mimics performed by a combination of NMR spectroscopy, and molecular mechanics and dynamics calculations showed a strong dependence of the RGD cyclopeptide conformation on lactam ring size and stereochemistry. ST1646 revealed the highest ability within the library to adopt the proper RGD orientation required for binding to the alpha(v)beta3 integrin, as deduced from the recently solved crystal structure of the extracellular segment of integrin alpha(v)beta3 in complex with a cyclic pentapeptide ligand.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Oligopéptidos
/
Integrinas
/
Aminoácidos
Límite:
Animals
Idioma:
En
Revista:
Bioorg Med Chem
Asunto de la revista:
BIOQUIMICA
/
QUIMICA
Año:
2006
Tipo del documento:
Article
País de afiliación:
Italia