Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 2002
Publication Date: July 15, 2002
Citation: SIRVENT, T.M., MCLANE, H., TSANG, C., KRASNOFF, S., GIBSON, D.M., CHURCHILL, A.C. CHEMICAL AND GENETIC ANALYSES OF PIGMENT BIOSYNTHESIS IN THE CHESTNUT BLIGHT FUNGUS. AMERICAN PHYTOPATHOLOGICAL SOCIETY ANNUAL MEETING. 2002.
Cryphonectria parasitica synthesizes orange and yellow pigments, which are aromatic polyketides that exhibit numerous biological activities in vitro. The roles of the pigments in the biology of the fungus are unknown. We isolated 15 mitotically stable mutants that are altered in pigment production by insertional mutagenesis. We developed a HPLC method for the characterization of the pigments from crude extracts. Chemical analyses of pigment mutants showed significant alterations in amounts and ratios of known and unknown pigments. Aloe emodin was detected for the first time in C. parasitica in several of the pigment mutants, and several unknown compounds are being characterized by LC MS. Using PCR amplification with degenerate primers designed to conserved domains of polyketide synthase (PKS) genes, we cloned 10 unique fragments with similarity to known PKSs. Complementation analyses of pigment mutants with PKS containing cosmids are in progress to identify a cosmid that restores polyketide pigment production.