PROTOPORPHYRINOGEN OXIDASE GENE AND ITS USE

摘要

PROBLEM TO BE SOLVED: To obtain the subject gene that is useful for artificially control the biosynthesis of plant porphyrin by the genetic engineering and can be used for breeding. SOLUTION: This gene encodes the protein that has the amino acid sequence of the formula and the protoporphyrinogen oxidase(PPO) activity. A PPO gene (hem G gene locus)-defective mutant strain of Escherichia coli is infected with the cDNA library based on the RNA extracted from the leaves and stems of soybean plants, grown on an agar culture medium and then colonies are selected to obtain the strain having the clone of the cDNA of the PPO gene originating from soybean plants. This phage clone having this cDNA is recovered to select the phage clone bearing the longest insert DNA and the PPO gene is cloned again to identify the base sequence of the incorporated DNA fragments. Then, the results are analyzed with the commercially available gene analysis software to identify the whole base sequence of the gene according to the present invention.