The conformation of the head-to-tail cyclic analogue of bradykinin in DMSO was investigated by nmr. Three sets of resonances were detected and fully assigned These were attributed to the presence of three stable conformers, two of which were exchanging on the nmr time scale. A fourth, incomplete set of resonances was detected but not assigned. The three major conformers differ in the conformation at the three X-Pro bonds present. From nuclear Overhauser effect spectroscopy (NOESY) spectra, three sets of interproton distances were derived and used in NOE-restrained distance geometry calculations. The resulting structures were refined by energy minimization to yield families of structures. Conformer I is characterized by the presence of two type VIb beta-turns between Arg(1) and Gly(4) and between Phe(5) and Phe(8). The first beta-turn is present also in conformer II, while an inverse gamma-turn bridging Pro(3) is the most pronounced structural feature of conformer III. (C) 1995 John Wiley & Sons, Inc.

Conformation of Cyclobradykinin By Nmr and Distance Geometry Calculations

MAMMI, STEFANO;GOBBO, MARINA;ROCCHI, RANIERO;PEGGION, EVARISTO
1995

Abstract

The conformation of the head-to-tail cyclic analogue of bradykinin in DMSO was investigated by nmr. Three sets of resonances were detected and fully assigned These were attributed to the presence of three stable conformers, two of which were exchanging on the nmr time scale. A fourth, incomplete set of resonances was detected but not assigned. The three major conformers differ in the conformation at the three X-Pro bonds present. From nuclear Overhauser effect spectroscopy (NOESY) spectra, three sets of interproton distances were derived and used in NOE-restrained distance geometry calculations. The resulting structures were refined by energy minimization to yield families of structures. Conformer I is characterized by the presence of two type VIb beta-turns between Arg(1) and Gly(4) and between Phe(5) and Phe(8). The first beta-turn is present also in conformer II, while an inverse gamma-turn bridging Pro(3) is the most pronounced structural feature of conformer III. (C) 1995 John Wiley & Sons, Inc.
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11577/2510879
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 11
  • ???jsp.display-item.citation.isi??? 11
social impact