Abstract: A method of determining the three-dimensional structure for proteins in aqueous solution by a set of distance constraints between backbond atoms (mainly for H-H, obtained from NMR) was developed. In this method, only dihedral angles were selected as independent variables, a proper target function was minimized by local-to-globular optimization, thus these dihedral angles and the coordinates of six kinds of the backbond atoms (N, H^N, C^α, H^α, C', O) were calculated. The program DISNMA for this method was designed, and proved with the standad structure of BPTI. It requires less amount of memory space and computing time and can be used for other larger molecules.

Key words: Protein comformation, NMR, Algorithm