Submitted to: Free Radical Biology and Medicine
Publication Type: Abstract only
Publication Acceptance Date: 7/8/2004
Publication Date: 11/13/2004
Citation: Baker, C.J., Whitaker, B.D., Mock, N.M., Rice, C., Roberts, D.P., Deahl, K.L., Averyanov, A.A. 2004. Stimulatory effect of acetosyringone on plant/pathogen recognition. Free Radical Biology and Medicine. Interpretive Summary:
Technical Abstract: Plants produce a broad variety of phenolic compounds. Much of the interest in these compounds is due to their potential beneficial bioactivity in humans and animals such as anti-depressants or anti-tumor activity. In plants, key roles for these phenolics include acting as antibiotics in fungal diseases, building blocks for lignin providing structural strength, and antioxidants to counter prooxidants produced during pathogen or environmental stresses. Very little attention has been given to the bioactive nature of these compounds in plants to determine if they affect physiological events or interactions. We have found that extracellular phenolics buildup in suspension cells and ameliorate the oxidative burst triggered by incompatible pathogens. One of the antioxidants was identified as acetosyringone. Acetosyringone produced in plant wounds has been documented to trigger genes in Agrobacterium tumefaciens that allow plant transformation to occur. We found acetosyringone to be bioactive in plant/bacterial interactions in that it sped up recognition of the incompatible pathogen by plants, which can be monitored by oxygen consumption. Acetosyringone buildup in plants is induced by bacteria and increases with increased bacterial concentration. It is redox sensitive in that its concentration is reduced by oxidative events associated with the pathogen interaction. This demonstrates that acetosyringone is a bioactive redox sensitive antioxidant.