Thaumatin-like protein in kiwifruit

A 21-kDa protein extracted from woody tissue underlying the pedicel of kiwi fruit (Actinidia deliciosa var deliciosa [A Chev] Liang and Ferguson) was p urified to homogeneity by cation exchange, gel filtration, sodium dodecyl s ulphate polyacrylamide gel electrophoresis (SDS-PAGE) on a 15% gel and elec tro-transfer onto a polyvinylidene difluoride (PVDF) membrane, followed by excision of the band of interest. Amino terminal sequence analysis of this band revealed a high degree of homology with basic endochitinase (EC 3.2.1. 14) in orange and thaumatin-like proteins in tobacco, barley, maize and tom ato. This is the first record of a thaumatin-like protein in a subtropical berryfruit. Potential implications of this finding and the need for future research are discussed. (C) 1999 Society of Chemical Industry.