SAR in plants is found to correlate with induction of a set of putative defense genes including PR proteins (Linthorst, 1991). The PR proteins are a group of extracellular proteins that are induced by different phytopathogens such as viruses, bacteria, and fungi, and SAR-inducing compounds such as salicylic acid and 2,6-dichloroisonicotinic acid (Bol et al., 1990; Uknes et al., 1992). These pro...

We have purified a 21-kDa protein, designated as P1, from Rehmannia glutinosa to homogeneity by ammonium sulfate precipitation, anion exchange chromatography, hydrophobic interaction chromatography, and preparative native PAGE. The purified P1 had chitin degradation activity. The N-terminal amino acid sequence of P1 indicated that it is very similar to those of thaumatin and other reported thau...

Background Oral allergy syndrome to sapodilla plum is caused by a 21 kD allergen existing as two isoforms: an acidic thaumatin-like protein (TLP-1) and a basic thaumatin-like protein (TLP-2). The composite sequence of TLP-1 comprising the N-terminal sequence 1-7 (A-T-F-D-V/I-V-N-) and the deduced sequence 8-207 (GenBank JN624813.1) was used for this analysis. The major objective of this study w...

Thaumatin, an intensely sweet protein, is the major proteinaciouscompnentinthe arils ofThaumatococcusdaniellii [l].Thaumatinisamemberofafamilyofatleastfiveisoforms, separable on cation exchange chromatography and all with a molecular weight of approx. 22 kDa and possessing eight disulphide bridges. Thaumatin I and II are derived from distinct genes, the other subforms may result from post-trans...

Wheat (Triticum aestivum) contains a previously unknown type of xylanase (EC 3.2.1.8) inhibitor, which is described in the present paper for the first time. Based on its >60% similarity to TLPs (thaumatin-like proteins) and the fact that it contains the Prosite PS00316 thaumatin family signature, it is referred to as TLXI (thaumatin-like xylanase inhibitor). TLXI is a basic (pI> or =9.3 in isoe...

The protein composition of the grape (Vitis vinifera cv Muscat of Alexandria) berry was examined from flowering to ripeness by gel electrophoresis. A protein with an apparent molecular mass of 24 kD, which was one of the most abundant proteins in extracts of mature berries, was purified and identified by amino acid sequence to be a thaumatin-like protein. Combined cDNA sequence analysis and ele...

To clarify the structural basis for the sweetness of thaumatin I, lysine-modified derivatives and carboxyl-group-modified derivatives were prepared by chemical modification followed by chromatographic purification. The sweetness of derivatives was evaluated by sensory analysis. Phosphopyridoxylation of lysine residues Lys78, Lys97, Lys106, Lys137 and Lys187 markedly reduced sweetness. The inten...