Purification of cationic peroxidases bound ionically to the cell walls from the roots of Zinnia elegans

Cell wall-bound and tracheary element-specific peroxidase isoenzymes, designated P5A and P5B, were shown previously to be associated with lignification during the differentiation into tracheary elements of single cells isolated from the mesophyll of Zinnia elegans (Sate et al. Planta 189: 584-589, 1993; Planta 196: 141-147, 1995). Isoenzymes corresponding to P5 (RP5A and RP5B) were present at a relatively high level in the roots of Zinnia elegans. These isoenzymes were purified from the Zinnia roots by several column-chromatographic steps. Both RP5A and RP5B had molecular masses of 35 kDa. purified RP5A and RP5B were cleaved by CNBr and the partial amino acid sequences of these isoenzymes were determined.