Solution conformation of brazzein by H-1 nuclear magnetic resonance: resonance assignment and secondary structure

Brazzein is a sweet-tasting protein isolated from the fruit of the West Afr ican plant Pentadiplandra brazzeana Baillon. It is the smallest and the mos t water-soluble sweet protein discovered so far, it is also highly thermost able. The proton NMR study of brazzein at 600 MHz (pH 3.5, 300K) is present ed. Complete sequence specific assignment of the individual backbone and si dechain proton resonances were achieved using through-bond and through-spac e connectivities obtained from standard two-dimensional NMR techniques. The secondary structure of brazzein contains one alpha-helix (residues 21-29), one short 3(10)-helix (residues 14-17), two strands of antiparallel beta-s heet (residues 34-39, 44-50) and probably a third strand (residues 5-7) nea r the N-terminus. (C) 1999 Elsevier Science B.V. All rights reserved.