Figure 1. Transcription with M. tuberculosis promoters. A Scheme of transcription initiation. B Sequences of promoters used in this study.

The -35, -10 elements and the transcription start sites are underlined. Sequences are aligned with E. coli σ⁷⁰ and mycobacterial σ^A dependent promoter consensus. C in vivo reporter assays. Transcriptional activities of the promoters were determined by β-galactosidase reporter assays from the early exponential phase cultures of M. smegmatis. The promoter activities are represented in Miller units on Y axis. D Growth curve of M. smegmatis . The OD₆₀₀ of the culture was recorded at 0, 6, 12, 24, 30, 36 and 48 Hrs. The time points at which the β-galactosidase reporter assays were carried out are indicated with asterisks. E in vivo reporter assays in different phases of growth. M. smegmatis cells harbouring pSD5B promoter constructs were grown upto 48 hours and promoter activity was determined at different times of growth by β-galactosidase assay as mentioned above.