The Conformation of α-Human Atrial Natriuretic Polypeptide in Solution

The three-dimensional structure of α-human ANP in solution was determined through the combined use of nuclear magnetic resonance spectroscopy and distance geometry. The results are based on distance constraints determined by nuclear Overhauser effect measurements and one disulfide bond. The structure is as follows. Three separate regions, which are Ser¹-Cys⁷, Arg¹¹-Ile¹⁵, and Gln¹⁸-Tyr²⁸ each have some ordered structure. The remaining parts in the sequences of Gly⁹-Gly^l0 and Gly¹⁶-Ala¹⁷ act as hinges. And the C-terminal part is folded back toward the cyclic moiety. The conformation of α-hANP reported here is expected to give a better understanding of the relationships between its biological activities and three-dimensional structure.