R. Bhaskaran et al., NMR AND DYNAMICAL SIMULATED ANNEALING STUDIES ON THE SOLUTION CONFORMATION OF UROTENSIN-II, Biochimica et biophysica acta (G). General subjects, 1199(2), 1994, pp. 115-122
We determined the structure in solution of the vase-constrictor hormon
e urotensin II (dodecapeptide) using nuclear magnetic resonance spectr
oscopy. Complete assignment of all proton resonances has been achieved
and the structural information has been obtained from the interproton
distance measurements derived from the nuclear Overhauser enhancement
data. A combination of distance geometry and dynamical simulated anne
aling techniques was used to calculate the structure in solution. Nine
resultant structures with fewer distance constraint violations were s
elected that satisfy the experimental restraints very well. The confor
mation of the molecule in the cyclic hexapeptide segment (core region)
is well-defined whereas the N-terminal segment is disordered. This re
sult correlates very well with the earlier predictions about the biolo
gically active and inactive roles played by the core and the N-termina
l segment respectively.