NMR ANALYSIS OF MOLECULAR FLEXIBILITY IN SOLUTION - A NEW METHOD FOR THE STUDY OF COMPLEX DISTRIBUTIONS OF RAPIDLY EXCHANGING CONFORMATIONS- APPLICATION TO A 13-RESIDUE PEPTIDE WITH AN 8-RESIDUE LOOP

A new methodology, called NAMFIS (NMR analysis of molecular flexibilit y in solution), is described for the analysis of flexible molecules in solution. Once a complete set of conformations is generated and is ab le to encompass all the possible states of the molecule that are not a priori incompatible with the available experimental NMR evidence, NAM FIS allows for the examination of the occurrence and relevance of arbi trary elements of secondary structure, even when extensive conformatio nal averaging defies a detailed experimental characterization. The:ana lysis is based on the available experimental NMR data.