We previously reported that inhibition of the Na⁺ translocating NADH:ubiquinone oxidoreductase (NQR), either by chemical inhibition or mutation, increased toxT transcription in Vibrio cholerae. In this study, we revealed that the nqr mutant strain showed similar phenotypes as the Escherichia coli NADH dehydrogenase I (nuo) mutant strain (e.g. growth defect...