Figure 7.

Translation of bmrB is essential for efficient and lincomycin-induced transcription of bmrCD. A. Schematic representation of plasmid pRM3-bmrBΔstart with the sequences of the first 15 nucleotides of bmrB and bmrBΔstart, and 70 nucleotides of the 5′-UTR. The mutations that were introduced to preclude translation of bmrB are marked with an asterisk (*). B. Maximum GFP expression values (AU) obtained from B. subtilis carrying pRM3-bmrB162 or pRM3-bmrBΔstart in response to xylose induction, either with or without lincomycin (0.75 μg/ml). C. ErmC-mediated methylation of the lincomycin-binding site on the ribosome prevents lincomycin-induced expression of bmrB-gfp. B. subtilis cells carrying pRM3-bmrB162 were pre-cultured in medium with or without erythromycin (0.5 μg/ml) and maximum GFP expression values were measured upon xylose induction, either with or without lincomycin (0.75 μg/ml). Culturing of cells in the presence of erythromycin induces expression of the ermC gene located on pRM3.