Validation of DNA microarray results using quantitative real-time reverse-transcription PCR (RT-qPCR).

<p>Log₂ fold-changes of transcript levels measured with DNA microarrays (x-axis) and RT-qPCR (y-axis) in <i>C</i>. <i>botulinum</i> ATCC 3502 continuous culture 10 min (red) and 42 h (black) after temperature up-shift from 39 to 45°C. 16S <i>rrn</i> transcript levels were used as a normalization reference in the RT-qPCR. Linear regression analysis showed an R² correlation value of 0.99 between the microarray and RT-qPCR transcription fold-change results.</p

Number of CDSs of <i>Clostridium botulinum</i> ATCC 3502 being significantly up-regulated (red), down-regulated (green) or unaffected (grey) after exposure to high temperature at different time points after heat shock.

<p>1: immediately after heat shock, 2: 10 min, 3: 1 h, 4: 18 h, 5: 42 h after heat shock, 6: adapted culture.</p

Gene expression profile of <i>Clostridium botulinum</i> ATCC 3502 showing the average fold-change in gene expression at 45°C compared to growth at 39°C of the significantly heat-affected genes assigned to clusters 1 through 6.

<p>In brackets: number of genes in cluster. Time point 1: immediately after heat shock, 2: 10 min, 3: 1 h, 4: 18 h, 5: 42 h after heat shock, 6: adapted culture. Error bars: standard deviation.</p