Host range of a plant pathogenic fungus determined by a saponin detoxifying enzyme.
Antifungal saponins occur in many plant species and may provide a preformed chemical barrier to attack by phytopathogenic fungi. Some fungal pathogens can enzymatically detoxify host plant saponins, which suggests that saponin detoxification may determine the host range of these fungi. A gene encoding a saponin detoxifying enzyme was cloned from the cereal-infecting fungus Gaeumannomyces graminis. Fungal mutants generated by targeted gene disruption were no longer able to infect the saponin-containing host oats but retained full pathogenicity to wheat (which does not contain saponins). Thus, the ability of a phytopathogenic fungus to detoxify a plant saponin can determine its host range.
Bowyer
P
P
Sainsburg Laboratory, John Innes Centre, Norwich, UK.
Clarke
B R
BR
Lunness
P
P
Daniels
M J
MJ
Osbourn
A E
AE
D001203:Ascomycota / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D018554:Avena / Q000382:microbiology*; D003001:Cloning, Molecular; D005656:Fungal Proteins; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D009154:Mutation; D009492:Neurospora crassa / Q000235:genetics; D012503:Saponins / Q000032:analysis* / Q000037:antagonists & inhibitors* / Q000378:metabolism; D014170:Transformation, Genetic; D014908:Triticum / Q000382:microbiology*; D001617:beta-Glucosidase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
D005656:Fungal Proteins; D012503:Saponins; C091460:avenacin A 1; C091461:avenacinase protein, Gaeumannomyces graminis; D001617:beta-Glucosidase