Abstract
KODA (9-hydroxy-10-oxo-12(Z),15(Z)-octadecadienoic acid), one of oxylipins formed with 9-lipoxygenase, has been found to be associated with flower induction of Lemna paucicostata [Yokoyama et al. (2000) Plant Cell Physiol. 41: 110-113; Yamaguchi et al. (2001) Plant Cell Physiol. 42: 1201-1209]. KODA biosynthesis is presumed to be formed with two enzymes, 9-lipoxygenase and allene oxide synthase [Feussner and Wasternack (2002) Annu. Rev. Plant Biol. 53: 275-297]. We here report the cloning of the 9-lipoxygenase from L. paucicostata for establishing the efficient production of KODA. Total RNA was extracted from L. paucicostata, SH and 441 strains, respectively. Partial sequences of the gene were obtained with degenerate PCR. Then, the complete cDNA sequences determined using 5' and 3' RACE gave one sequence from SH strain and two sequences from 441 strain. The lipoxygenase genes were introduced into E. coli and expressed. The recombinant proteins were examined in a reaction with α-linolenic acid as a substrate and confirmed to be 9-lipoxygenase.
