Journal: PLoS Pathogens
Article Title: Deciphering the Cryptic Genome: Genome-wide Analyses of the Rice Pathogen Fusarium fujikuroi Reveal Complex Regulation of Secondary Metabolism and Novel Metabolites
Figure Lengend Snippet: Functional characterization of the PKS19 cluster, a putative polyketide biosynthetic gene cluster that is unique to F. fujikuroi . (A) Position and organization of the PKS19 gene cluster on F. fujikuroi chromosome VIII, GC content, distribution of active histone marks, and gene expression in the PKS19 cluster. Histone marks are described in the legend for Figure 3 . Expression data are from microarray analysis of wild-type F. fujikuroi (strain IMI58289). Values are log 2 change in expression in a high versus low-nitrogen medium. H3K9ac and gene expression are correlated, as both are increased in the high-nitrogen medium. Some genes exhibited increased levels of H3K4me2 in the high-nitrogen medium, which also suggests transcription. (B) Chemical analysis of the SM product(s) of the PKS19 cluster. The traces show the combined extracted ion chromatograms for metabolites with molecular formulas [C 12 H 16 O 4 +H] + , [C 12 H 18 O 5 +H] + and [C 12 H 18 O 4 +H] + determined by HPLC-FTMS of culture fluids from F. fujikuroi strains: IMI58289, wild-type strain; OE::TF, a strain over-expressing the transcription factor encoded by FFUJ_12242; OE::PKS19, a strain over-expressing the PKS19 gene FFUJ_12239; and OE::TF/OE::PKS19, a strain over-expressing both FFUJ-12242 and FFUJ_12239. (C) Northern blot analysis of PKS19 cluster genes in strains IMI58289 (WT), OE::TF, OE::PKS19 and OE::TF/OE::PKS19. (D) UV spectra of metabolites corresponding to peaks 1 through 4 from chromatograms shown in C. The similar spectra of the metabolites suggest structural similarity.
Article Snippet: HPLC-FTMS The HPLC-FTMS system used an HPLC system (Accela LC with Accela Pump 60057-60010 and Accela Autosampler 60057-60020, Thermo Scientific, Dreieich, Germany) coupled to a Fourier transform mass spectrometer with a heated ESI source (LTQ Orbitrap XL, Thermo Scientific, Dreieich, Germany).
Techniques: Functional Assay, Expressing, Microarray, High Performance Liquid Chromatography, Northern Blot