Article Figures & Data
Figures
- Fig. 1.
Sequence of the slpA promoter region in the wild type and the Δ5′UTR mutants. The sequences of theslpA promoter of the wild type (A) and the HB8ΔUTRK1 (B) and HB8ΔUTR1 (C) mutants are shown. Gray boxes indicate the consensus −35, −10, and ribosome binding site (SD) sequences. The thick arrow indicates the transcription and the thin lines label the inverted repeats (ir) in the wild-type promoter. The N- and C-terminal amino acids of the Kat and SlpA proteins are shown under the sequences. The box in the wild-type promoter labels the 5′UTR sequence deleted in the mutants.
- Fig. 2.
Expression of the slpA gene in Δ5′UTR mutants. (A) The stability of the slpA mRNA from the wild type (Wt) and the HB8ΔUTRK1 (ΔUTRK1) and HB8ΔUTR1 (ΔUTR1) mutants is analyzed. Exponential cultures of the three strains grown up to an optical density at 550 nm (OD550) of 0.8 were treated with rifampin (200 μg/ml) and identical cell mass samples were taken after 0, 5, 10, and 15 min of incubation at 70°C. The detection of the slpA mRNA was developed by Northern blotting with the specific oligonucleotide O-slpA1. (B) Transcription of the slpA gene along the growth of the wild type and the Δ5′UTR mutants. The optical densities at 550 nm of parallel cultures of the HB8 strain (black circles) and its derivatives HB8ΔUTRK1 (white squares) and HBRΔUTR1 (white circles) were monitored along the times indicated. Identical cell mass samples were taken at the times indicated by the black (wild type) and white (mutants) arrows and analyzed for the presence of slpA mRNA by Northern blotting.
- Fig. 3.
Effect of the Δ5′UTR mutation on cell morphology. (A and B) Phase-contrast micrographs of overnight cultures of the wild type (A) and the HB8ΔUTR1 mutant (B). (C) Thin section of an overnight culture of the HB8ΔUTR1 mutant showing the intercellular continuity of the external envelope. The bar corresponds to 0.5 μm.
