The flavohemoglobin BCFHG1 is the main NO detoxification system and confers protection against nitrosative conditions but is not a virulence factor in the fungal necrotroph Botrytis cinerea.
Flavohemoglobins constitute a group of proteins involved in the metabolism of nitric oxide (NO). Botrytis cinerea was shown to have a single flavohemoglobin coding gene, Bcfhg1. Its expression was developmentally regulated, with maximum expression levels during germination of conidia, and was enhanced very quickly upon exposure to NO of germinating conidia, but not of mycelium growing and branching actively. Expression in planta paralleled the expression pattern during saprophytic growth with maximal expression occurring during the very early stages of the infection process. Bcfhg1 complemented the Saccharomyces cerevisiae yhb1 mutation, indicating that the encoded enzyme has NO dioxygenase activity. Biochemical and functional characterization of DeltaBcfhg1 mutants in comparison with the wild type strain demonstrated that, although BCFHG1 showed a high affinity for its substrate, appeared to represent the main inducible NO detoxification system and conferred protection against nitrosative stress in B. cinerea, the ability of the DeltaBcfhg1 mutant strains to infect different hosts was not affected.
Turrion-Gomez
Juan Luis
JL
Centro Hispano-Luso de Investigaciones Agrarias (CIALE), Departamento de Microbiología y Genética, Universidad de Salamanca. C. Río Duero, No. 12., Campus de Villamayor, Parque Científico, 37185 Villamayor, Salamanca, Spain.
Eslava
Arturo P
AP
Benito
Ernesto P
EP
D020171:Botrytis / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D006420:Hemeproteins / Q000235:genetics / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000382:microbiology; D008969:Molecular Sequence Data; D009569:Nitric Oxide / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
D005656:Fungal Proteins; D006420:Hemeproteins; D037521:Virulence Factors; D009569:Nitric Oxide