Fig. 3

CydC Mediated [EMIM]OAc Tolerance Does Not Act Through cytochrome bd-I. a Schematic. Proposed relationship between CydC and cytochrome bd-I if [EMIM]OAc tolerance in CydC-D86G strains is due to directly activating cytochrome bd-I. b Conservation of cydC and cytochrome bd-I subunit cydB by strict (> 95% identity) homolog identification in bacteria. cydB is observed in a subset of species with detected cydC homologs. c Peroxide challenge assay. Wild-type DH1 cells or DH1 cydC-D86G cells grown in the presence of exogenous 30 mM hydrogen peroxide over a 20 h timeframe. No difference in hydrogen peroxide sensitivity was observed. Optical density (OD) is plotted on a log₁₀ scale. d Tolerance to [EMIM]OAc in improved cytochrome bd-I cells. E. coli BW25113 ∆oppF [P_trc-cydAB] or wild-type cells were grown in the presence of 50 mM [EMIM]OAc. Functional cytochrome bd-I activity was increased with 200 µM IPTG. Growth of cells was monitored over a 40 h timeframe. Optical density is plotted on a log₁₀ scale