Thaumatin conformation

Tancredi, T., Pastore, A., Salvatori, S., Esposito, V., and Temussi, P.A. (2004). Interaction of sweet proteins with their receptor A conformational study of peptides corresponding to loops of brazzein, monellin and thaumatin. Eur. J. Biochem. 271, 2231-2240. 

Fig. 8.7. A two dimensional representation of the conformation of the peptide chains of monellin (a) and thaumatin (b). (p-structure a-helix d p-turn d ...

Fig. 8.8. A stereoscopic representation of the conformation of the peptide chains of mon-ellin top) and thaumatin bottom) (the location of tryptic peptides that cross react with heterologous antibodies is indicated by thicker lines) (according to Kim et aL, 1991)...

The fruit of Thaumatococcus daniellii contains two sweet proteins thaumatin I and II, with /sac,g 2000. There are also low amounts of three other sweet proteins (thaumatin a, b and c). The complete amino acid sequence and the conformation (Fig. 8.7 and 8.8) of thaumatin I, a peptide chain with 207 amino acid residues, has been established (Table 8.5). As a result of cross reactions with an anti-serum against monellin (cf. 8.8.4), sequence Y(57)FD in a j3-tum is regarded as the site of contact with the sweetness receptor. It corresponds to sequence Y(A13)ASD of monellin. 

---