Validation of microarray data by real-time RT-PCR.

<p>Relative gene expression (A) in 2.4.1Δ<i>irr</i> under normal iron conditions compared to the wild type under normal iron conditions and (B) in 2.4.1Δ<i>irr</i> under iron limitation compared to normal iron conditions (light gray bars) and in wild type under iron limitation compared to normal iron conditions (dark gray bars). Values were normalized to <i>rpoZ</i> and to the respective control treatment. The data represent the mean of at least three independent experiments and error bars indicate standard deviation. Numbers in parentheses show the fold change of the respective genes as determined by microarray analysis.