Multi-conformational peptide dynamics derived from NMR data: a new search algorithm and its application to antamanide.

R Brüschweiler; M Blackledge; R R Ernst

doi:10.1007/bf01874565

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Multi-conformational peptide dynamics derived from NMR data: a new search algorithm and its application to antamanide.

R Brüschweiler·M Blackledge·R R Ernst

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Abstract

A search algorithm, called MEDUSA, is presented which allows the determination of multiple conformations of biomolecules in solution with exchange rate constants typically between 10(3) and 10(7) s-1 on the basis of experimental high-resolution NMR data. Multiples of structures are generated which are consistent as ensembles with NMR cross-relaxation rates (NOESY, ROESY), scalar J-coupling constants, and T1 rho measurements. The algorithm is applied to the cyclic decapeptide antamanide dissolved in chloroform. The characteristic radio-frequency field dependence of the T1 rho relaxation rates found for the NH protons of Val1 and Phe6 can be explained by a dynamical exchange between two structures.

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Algorithms Amino Acid Sequence Magnetic Resonance Spectroscopy Models, Molecular Molecular Conformation Molecular Sequence Data Peptides Peptides, Cyclic Journal Article Research Support, Non-U.S. Gov't

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R Brüschweiler, M Blackledge, R R Ernst. 1991. Multi-conformational peptide dynamics derived from NMR data: a new search algorithm and its application to antamanide.. https://doi.org/10.1007/bf01874565

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