Transcriptional profiling of the T. thermophilus HB8 response to tetracycline (low concentration)

We observed the expression profile of the total mRNA in Thermus thermophilus HB8 wild-type strain at 5 min after the addition of 10 mM tetracycline. Three wild-type strain of T. thermophilus HB8 were pre-cultured at 70 degC for 16 hours in 3 mL of TT medium containing 0.8% polypeptone, 0.4% yeast extract, 0.2% NaCl, 0.4 mM CaCl2, and 0.4 mM MgCl2, which was adjusted to pH 7.2 with NaOH. The cells (2 mL) were inoculated into 1 L of the same medium and then cultivated at 70°C for 5 hours (A600 value being ~0.47). Then the 10 mM of tetracycline was added into the medium, and continued cultivation. Cells were collected at 5 min time point after the addition of tetracycline, and then crude RNA was extracted. The expression of each mRNA was analyzed on a GeneChip.