FIG. 8.

Detection of cipC-cel48F and cel48F mRNA stabilities by Northern blot analyses. (A) Total RNAs were purified from cells grown at 32°C before addition of rifampin. RNAs were extracted at the indicated times (0, 9, 20, and 30 min) after addition of rifampin. The blotted RNAs were hybridized with cel48F- and 16S-specific Cy5-labeled cDNA probes. (B) Half-life determination of the cipC-cel48F (▪) and cel48F (▴) transcripts. Each RNA was quantified from the intensity of the corresponding area minus background contribution using the Multi Gauge, version 2.0, software. In order to compare the quantities of the two specific-mRNAs in the four samples, these quantities were normalized relatively to the extremely stable 16S RNA. This experiment has been performed twice with samples collected at different times (data not shown). Half-lives determined from each mRNA species from the two different experiments were equal.