TY - JOUR
T1 - Peroxidases and the metabolism of hydroxycinnamic acid amides in Poaceae
AU - Kristensen, Brian Kaare
AU - Burhenne, Kim
AU - Rasmussen, Søren Kjærsgaard
PY - 2004/1/1
Y1 - 2004/1/1
N2 - The arsenal of plants to fight off microorganisms and herbivores include hydroxycinnamic acid amides (HCAA) and their oxidation products. Hydroxycinnamic acid amides are widespread in the plant kingdom and in the recent years our knowledge of their biosynthesis and catabolism has increased substantially. Peroxidases are the primary candidates as the oxidative enzymes responsible for the turnover of hydroxycinnamic acid amide monomers. In barley, hydroxycinnamoylagmatine derivatives accumulate in young seedlings and in tissues infected with fungi. Hydroxycinnamoylagmatine is found as anti-fungal soluble dimers, called hordatines, and it is also a likely constituent of cell walls. Current evidence suggest that peroxidases are involved in the cross-linking of hydroxycinnamoylagmatine with cell wall components and possibly also in the synthesis of hordatines. Epidermal cell walls of barley respond to infection by the powdery mildew fungus with the deposition of polyphenolic material, that apparently contains hydroxycinnamic acid amides, at the site of attempted penetration. Accumulation of these compounds lowers the successful penetration by the fungus. The recent characterization of agmatine coumaroyl transferase (ACT), the N-hydroxycinnamoyltransferase responsible for the synthesis of hydroxycinnamoylagmatine in barley, has indicated that the production of these metabolites is widespread in the plant body and suggests multiple physiological functions for HCAA derivatives. The cloning of ACT has enabled the revelation of homologues genes in several monocots and the presence of a range of structurally diverse HCAAs in cereals suggests that their peroxidase-mediated metabolism is a common theme. The prospects for metabolic engineering of these pathways into other crops are discussed.
AB - The arsenal of plants to fight off microorganisms and herbivores include hydroxycinnamic acid amides (HCAA) and their oxidation products. Hydroxycinnamic acid amides are widespread in the plant kingdom and in the recent years our knowledge of their biosynthesis and catabolism has increased substantially. Peroxidases are the primary candidates as the oxidative enzymes responsible for the turnover of hydroxycinnamic acid amide monomers. In barley, hydroxycinnamoylagmatine derivatives accumulate in young seedlings and in tissues infected with fungi. Hydroxycinnamoylagmatine is found as anti-fungal soluble dimers, called hordatines, and it is also a likely constituent of cell walls. Current evidence suggest that peroxidases are involved in the cross-linking of hydroxycinnamoylagmatine with cell wall components and possibly also in the synthesis of hordatines. Epidermal cell walls of barley respond to infection by the powdery mildew fungus with the deposition of polyphenolic material, that apparently contains hydroxycinnamic acid amides, at the site of attempted penetration. Accumulation of these compounds lowers the successful penetration by the fungus. The recent characterization of agmatine coumaroyl transferase (ACT), the N-hydroxycinnamoyltransferase responsible for the synthesis of hydroxycinnamoylagmatine in barley, has indicated that the production of these metabolites is widespread in the plant body and suggests multiple physiological functions for HCAA derivatives. The cloning of ACT has enabled the revelation of homologues genes in several monocots and the presence of a range of structurally diverse HCAAs in cereals suggests that their peroxidase-mediated metabolism is a common theme. The prospects for metabolic engineering of these pathways into other crops are discussed.
KW - Barley
KW - Cell wall
KW - Defence
KW - Hydroxycinnamic acid amide
KW - Pathogenic fungi
UR - http://www.scopus.com/inward/record.url?scp=23944456560&partnerID=8YFLogxK
U2 - 10.1023/B:PHYT.0000047800.59980.6e
DO - 10.1023/B:PHYT.0000047800.59980.6e
M3 - Review
AN - SCOPUS:23944456560
SN - 1568-7767
VL - 3
SP - 127
EP - 140
JO - Phytochemistry Reviews
JF - Phytochemistry Reviews
IS - 1-2
ER -