Influence of AreA and AreB on secondary metabolite cluster gene expression.

<p>The <i>F</i>. <i>fujikuroi</i> Wt and the Δ<i>AREA</i> and Δ<i>AREB</i> deletion mutants were cultivated for 3 (A, B, C) or 7 (D) days in ICI liquid cultures with 6 mM glutamine (6) or 60 mM glutamine (60) as sole nitrogen source. (A) Differentially regulated secondary metabolite gene clusters, represented by PKS-, NRPS-, TC- and DMATS-encoding genes. Data are based on microarray analysis. (B) Northern blot analysis of secondary metabolite cluster gene expression: <i>CPS/KS</i> (copalyl diphosphate/kaurene-synthase, GA-cluster), <i>BIK2</i> (monooxygenase, BIK-cluster), <i>APF6</i> (o-methyltransferase, APF-cluster), <i>FUB5</i> (homoserine o-acyltransferase, FUB-cluster). (C) Variation in pigmentation of the strains in ICI liquid culture. (D) Variation in bikaverin production. Culture supernatant was analyzed by HPLC-DAD. The peaks of bikaverin and norbikaverin were integrated at wavelength of 510 nm and depicted in relation to the total cell dry mass of the cultures.</p>