Phenotype and metabolism alterations in acid-induced Rhodococcus biphenylivorans TG9T

This work interprets the acid responses from metabolism in strain Rhodococcus biphenylivorans TG9T induced at pH3. To compare the expression regulations effected by acid stress, four treatment samples were prepared for transcription analysis, including LP sample (log phase with OD600 = 1.2), PER sample (the log-phase culture was induced with acid for 7 days), RE sample (the log-phase culture was induced 20 days until no culturability and then resuspended in neutral LB for 48 h until its OD600 start rising), REL sample (the resuspension is incubated for another 12 h with obvious OD600 rise (around 1.6 in three replicates)). Each of the treatments was in three biological replicates.