The primary structure of the cDNA clone SF28 was determined in sunflower (H
elianthus annuus L.) flowers. The clone comprises a 874-bp insert correspon
ding to 227 amino acid residues of the C-terminal part of the cytochrome P4
50 gene. The sunflower cytochrome P450 was considerably different from the
already known plant and animal cytochromes P450.