Siderophore synthesis in Magnaporthe grisea is essential for vegetative growth, conidiation and resistance to oxidative stress.
The plant pathogenic fungus Magnaporthe grisea excretes siderophores of the coprogen-type for iron acquisition and uses ferricrocin for intracellular iron storage. In the present report we characterize mutants with defects in extracellular siderophore biosynthesis. Deletion of the M. grisea SSM2 gene, which encodes a non-ribosomal peptide synthetase, resulted in a loss of the production of all coprogens. The mutant strains had a reduced growth rate, produced fewer conidia and were more sensitive to oxidative stress. Ferricrocin production was not affected. Upon deletion of M. grisea OMO1, a gene predicted to encode an L-ornithine-N(5)-monooxygenase, no siderophores of any type were detected, the strain was aconidial, growth rate was reduced and sensitivity to oxidative stress was increased. Abundance of several proteins was affected in the mutants. The Deltassm2 and Deltaomo1 mutant phenotypes were complemented by supplementation of the medium with siderophores or reintroduction of the respective genes.
Hof
Carolin
C
Institut für Biotechnologie und Wirkstoff-Forschung e.V., Kaiserslautern, Germany.
Eisfeld
Katrin
K
Antelo
Luis
L
Foster
Andrew J
AJ
Anke
Heidrun
H
D005656:Fungal Proteins / Q000235:genetics; D017353:Gene Deletion; D005816:Genetic Complementation Test; D020082:Magnaporthe / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D006899:Mixed Function Oxygenases / Q000235:genetics; D018384:Oxidative Stress; D010453:Peptide Synthases / Q000235:genetics; D017262:Siderophores / Q000096:biosynthesis*; D013172:Spores, Fungal / Q000254:growth & development*; D013312:Stress, Physiological
D005656:Fungal Proteins; D017262:Siderophores; D006899:Mixed Function Oxygenases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase