Fig. 5. HvAPX1 in contrast to plant ascorbate peroxidases lacks introns. RT PCR (lanes 1,3,5) and genomic PCR amplification (lanes 2,4,6) of Chlorella vulgaris 211-11b and Hydra viridis ascorbate peroxidase. PCR was carried out with one set of primers against the Chlorella APX peroxidase domain (lanes 1,2), another set against the homologous region of HvAPX1 (lanes 3,4), and a third pair of primers flanking the complete open reading frame of HvAPX1 (lanes 5,6). PCR with primers flanking the peroxidase domain resulted in fragment sizes of 527 bp (lane 1) from Chlorella cDNA and of about 1000 bp from Chlorella genomic DNA as well as 523 bp (lane 3) and 1123 bp (lane 5) from Hydra cDNA and equally sized genomic fragments (lanes 4,6). M, size markers.