Three proteins belonging to the thaumatin-like proteins family were compared in this study from a structural point of view: zeamatin, a new recently isolated PR-5 from Cassia didymobotrya and the commercial sweet-thaumatin. The former two proteins possess antifungal activities while commercial thaumatin is well known to be a natural sweetener. Intrinsic fluorescence studies have evidenced that the three proteins behave differently in unfolding experiments showing different structural rigidity. All the three proteins are more stable at slight acidic buffers, but sweet-thaumatin has a major tendency to destructurate itself. Similar observations were made from circular dichroism studies where a structural dependence relationship from the pH and the solvent used confirmed a hierarchic scale of stability for the three proteins. These structural differences should be considered to be significant for a functional role
Perri, F., Romitelli, F., Rufini, F., Secundo, F., Di Stasio, E., Giardina, B., Vitali, A., Different structural behaviors evidenced in thaumatin-like proteins: A spectroscopic study, <<PROTEIN JOURNAL>>, 2008; 27 (1): 13-20. [doi:10.1007/s10930-007-9103-2] [http://hdl.handle.net/10807/12297]
Different structural behaviors evidenced in thaumatin-like proteins: A spectroscopic study
Perri, Fabio;Romitelli, Federica;Di Stasio, Enrico;Giardina, Bruno;Vitali, Alberto
2008
Abstract
Three proteins belonging to the thaumatin-like proteins family were compared in this study from a structural point of view: zeamatin, a new recently isolated PR-5 from Cassia didymobotrya and the commercial sweet-thaumatin. The former two proteins possess antifungal activities while commercial thaumatin is well known to be a natural sweetener. Intrinsic fluorescence studies have evidenced that the three proteins behave differently in unfolding experiments showing different structural rigidity. All the three proteins are more stable at slight acidic buffers, but sweet-thaumatin has a major tendency to destructurate itself. Similar observations were made from circular dichroism studies where a structural dependence relationship from the pH and the solvent used confirmed a hierarchic scale of stability for the three proteins. These structural differences should be considered to be significant for a functional roleI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.