Wheat Pathogenesis-related Protein Thaumatin Protein Bioinformatics Analysis

Plant pathogenesis related (PR) proteins was responsible for the defense mechanism in the plant-pathologen interaction system. The thaumatin protein, as a member of plant PR protein, reported by several plant species, exhibits an important effect for plant resistant reaction. The most effective method to control the wheat powdery mildew, caused by Blumeria graminis f.sp tritici, is to grow wheat cultivars with disease resistance. Wheat thaumatin-like protein (TLP) has been considered to be related to the powdery mildew resistance. It is therefore interesting to study the member of wheat TLP at molecular level, with purpose to interprete the possible function for disease resistance. A wheat thaumatin-like protein, designated as TaTLP1 (GenBank accession number: AF384146) was cloned and sequenced. It was highly homologous to thaumatin proteins isolated from other plants. The objective of the study is to illustrate the chemical characters, possible function by the bioinformatics methods.1. The present wheat thaumatin-like protein (TaTLP1), whose expression was induced by fungus Erysiph graminis, has putative 173 amino acid residues. The TaTLP1 protein was predicted to be a acid protein with a THN domain. However, the great difference between the present TaTLP1 with other members of PR protein was the numbers of cysteine and bisulfide key. It is likely that this property may be related to wheat powdery mildew resistance. The homology comparision indicated that the present TaTLP1 protein was closed to the barley and rye in tribe of triticeae.2. Using internet-based Kyto & Doolittle, Hopp & Woods, as well as Vector NTI 8 software, the hydrophobicity analysis of the TaTLP1 protein indicated that the first 20 amino acids were highly hydrophobic, while the rest amino acids were of hydrophilicity, which may be a sequence of signal peptide. It is thus to conclude that the TaTLP1 was a signal independent...