Laccase is upregulated via stress pathways in the phytopathogenic fungus Sclerotinia sclerotiorum.
We report on the factors affecting the production of the newly characterized laccase from the phytopathogenic fungus Sclerotinia sclerotiorum (Lib.) de Bary. The carbon/nitrogen ratio appears to be of great importance. Rather than a simple nutrient-rich nitrogen source, yeast extract (YE) behaves as a true laccase upregulator, apparently acting via a stress pathway. Chelidonium majus extract, a known antifungal agent, acts in a similar manner. The compound(s) in the YE responsible for enhancing laccase synthesis are suggested to be hydrolysable choline derivatives. Both extracts reduce biomass and sclerotia development and enhance laccase production, leading to an increase in laccase activity by one order of magnitude compared to controls. The pH of the medium, a well-known virulence regulator for this fungus, also acts as a true laccase regulator, though via a different mechanism. The effect of pH appeared to be linked to the acidification kinetics of the extracellular medium during fungal development. A number of other known laccase inducers were found to enhance laccase production at most twofold.
Department of Chemistry and Chemical Engineering, 'Babeş-Bolyai' University, 1, M. Kogălniceanu Street, Cluj-Napoca RO-400084, Romania.
Cristina
C
Coman
Augustin C
AC
Moţ
Emese
E
Gal
Marcel
M
Pârvu
Radu
R
Silaghi-Dumitrescu
D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D002244:Carbon / Q000378:metabolism; D003470:Culture Media / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D006863:Hydrogen-Ion Concentration; D042845:Laccase / Q000235:genetics* / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D015854:Up-Regulation
D003470:Culture Media; D005656:Fungal Proteins; D002244:Carbon; D042845:Laccase; D009584:Nitrogen
Culture optimization; Laccase regulation; Sclerotinia sclerotiorum; Stress response; Yeast extract; pH