Inhibition of the pathogenicity of Magnaporthe grisea by bromophenols, isocitrate lyase inhibitors, from the red alga Odonthalia corymbifera.
Magnaporthe grisea is a fungal pathogen of rice that forms appressoria that penetrate the outer cuticle of the rice plant. Data from recent studies indicate that M. grisea isocitrate lyase (ICL), a key enzyme in the glyoxylate cycle, is highly expressed during appressorium-mediated plant infection. Bromophenols isolated from the red alga Odonthalia corymbifera exhibited potent ICL inhibitory activity and blocked appressoria formation by M. grisea in a concentration-dependent manner. In addition, these compounds protected the rice plants from infection by M. grisea. Rice plants infected with wild-type M. grisea Guy 11 exhibited significantly lower disease severity with bromophenol treatment than without, and the treatment effect was comparable to the behavior of the Deltaicl knockout mutant I-10. The protective effect of bromophenols and their strong inhibition of appressorium formation on rice plants suggest that ICL inhibitors may be promising candidates for crop protection, particularly to protect rice plants against M. grisea.
Lee
Hyi-Seung
HS
Marine Natural Products Laboratory, Korea Ocean Research and Development Institute, Ansan P.O. Box 29, Seoul 425-600, South Korea.
Lee
Tae-Hoon
TH
Lee
Ji Hye
JH
Chae
Choong-Sik
CS
Chung
Soon-Chun
SC
Shin
Dong-Sun
DS
Shin
Jongheon
J
Oh
Ki-Bong
KB
D001966:Bromine / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology; D005659:Fungicides, Industrial / Q000494:pharmacology*; D007522:Isocitrate Lyase / Q000037:antagonists & inhibitors*; D020082:Magnaporthe / Q000187:drug effects*; D012275:Oryza / Q000382:microbiology; D010636:Phenols / Q000494:pharmacology*; D010935:Plant Diseases / Q000382:microbiology; D000461:Rhodophyta / Q000737:chemistry*
D004791:Enzyme Inhibitors; D005659:Fungicides, Industrial; D010636:Phenols; D007522:Isocitrate Lyase; D001966:Bromine