FIGURE 6.

Model of the central metabolism indicating the shift from acetoin to ethanol production observed by all four antibiotics. Blue indicate decreased expression of lmo1992 and alsS and red indicate increased expression of lmo1634 by all four antibiotics. Pyruvate formate-lyase encoded by pflAC (light red) and involved in degradation of pyruvate under anaerobic condition is induced by gentamicin and co-trimoxazole but not ampicillin and tetracycline whereas pyruvate dehydrogenase encoded by pdhA (light blue) involved in degradation of pyruvate under aerobic condition are down-regulated by co-trimoxazole but not any of the other antibiotics. Broken circle illustrate the microcompartment in which ethanolamine is degraded and the degradation pathway of ethanolamine to ethanol and acetyl-CoA. Neither of the four genes lmo1179, lmo1171, lmo1165, or lmo1166 (gray) are differentially expressed by any of the four antibiotics.