|Kaeppler, Heidi - UNIV OF WISCONSON|
Submitted to: In Vitro Biology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: February 4, 2006
Publication Date: June 4, 2006
Citation: Wise, M.L. 2006. Biosynthesis of avenanthramides in chitin elicited oat (Avena sativa) suspension cultures [abstract]. In Vitro Biology Meeting. p. 34. Paper No. P-2002. Technical Abstract: Avenanthramides are polyphenolic alkaloids produced uniquely in oat. These metabolites stem from the phenylpropanoid and anthranilic acid biosynthetic pathways. Although numerous avenanthramides have been described, the three principle forms found in oat are conjugates of 5-hydroxy anthranilic acid and either p-coumaric, ferulic or caffeic acid (termed avenanthramide A, B and C respectively). Recent studies have shown that these phytonutrients can reduce exercise induced inflammation of muscle tissue in rats and that they also possess anti-atherosclerotic properties. In whole plants the avenanthramides are found primarily in leaf tissue, in response to fungal infection by the crown rust organism Puccinia coronata, and in the grain. In most oat cultivars all three avenanthramides are found in the grain; however the proportions and absolute quantities are highly variable depending on cultivar and growth environment. To investigate the signaling mechanisms and metabolic flux of this novel biosynthetic pathway we have developed a cell suspension system that is responsive to chitin elicitation. Hydroxycinnamoyl-CoA: hydroxyanthranilate N-hydroxycinnamoyl transferase (HHT) is the final enzyme in the biosynthetic pathway. Here we demonstrate the dynamics of HHT mRNA production, HHT enzyme activity and biosynthesis of avenanthramide A in response to elicitation with crude crab shell chitin in these oat cell cultures.