Figure 4.

Introduction of conformational flexibility results in cells with a switching phenotype and allosteric proteins. (a) Maltose-dependent fold increase in ampicillin resistance for cells expressing the indicated proteins at 18°C and 37°C. (b) Maltose-dependent fold increase in ampicillin resistance for cells expressing the indicated proteins grown in media with the indicated initial pH. The MIC_Amp ratio (+maltose/−maltose) was calculated using the median MIC_Amp value from three independent trials. (c) Maltose-dependent fold increase in initial rate of nitrocefin hydrolysis enzymatic activity of c4 and c4-3G at 18°C and 37°C. (d) Maltose-dependent fold increase in initial rates of nitrocefin hydrolysis enzymatic activity of c4 and c4-3hx at pH 6 and pH 8. Average rates were calculated from three independent trials.