Patent ID: 7586023

Claim:
A method of conferring resistance to protoporphyrinogen oxidase-inhibiting herbicides upon the green algae Chlamydomonas or cells thereof, comprising introducing a DNA fragment or a plasmid containing the DNA fragment into the algae or algal cells, wherein said DNA fragment has the following characteristics: (1) said DNA fragment is 2.6 to 13.8 kb in length; (2) said DNA fragment has a sequence that can be detected and isolated by DNA-DNA or DNA-RNA hybridization to a nucleic acid sequence that is complementary to a nucleotide sequence encoding the amino acid sequence of SEQ ID NO: 1, wherein said DNA-DNA or DNA-RNA hybridization occurs under 2×PIPES buffer, 50% deionized formamide, 0.5% (w/v) SDS, 500 μg/ml denatured sonicated salmon sperm DNA at 42° C. overnight; and said DNA fragment remains hybridized after washing in 0.2×SSC, 0.1% (w/v) SDS at 68° C.; (3) said DNA fragment encodes an amino acid sequence in which an amino acid at a position corresponding to position 13 of SEQ ID NO:1 is an amino acid other than valine; and (4) said DNA fragment has an ability to confer resistance to protoporphyrinogen oxidase-inhibiting herbicides in cells of the green algae Chlamydomonas when introduced therein.