Polymorphism and pedigree analysis of β-amylase isozymes in Australian wheat

β-Amylase encoded by multiple loci on chromosomes of triticeae crop plants is a starch metabolic enzyme with a significant physiological role in flour functionality. In this study, wheat grain β-amylase isozymes were characterized using an extensive Australian wheat population and genetic breeding/mapping lines. β-amylase isozymes were fractionated by high-resolution native polyacrylamide gel electrophoresis (PAGE) and validated by zymogram and peptide sequencing using electrospray ionization tandem mass spectrometry (ESI-MS/MS). Specific antibodies were generated against the β-amylase purified through protein chromatography and used for β-amylase identification. Further characterization of wheat β-amylases was carried out with immunoblotting and 2-dimensional electrophoresis (2-DE). The enzyme was found to be polymorphic among the Australian and foreign wheat cultivars, with a total of six isozymes: two common and four varying isozymes, the latter group including one novel β-amylase isozyme of fast-mobility in native PAGE, According to pedigree analysis, the origin of this particular isozyme was from the ancestral genotype, Ciano F 67.