MIC values and kinetic and stability parameters of TEM-1, single mutants R164S and G238S, and double mutant R164S/G238S.

The kinetic were acquired in vitro with purified proteins. The Tm and m values (indicating the cooperativity of unfolding) were extracted from heat denaturation. N.D.; not determined. Errors shown are standard deviations. Because of the high TEM-1 levels under induction, MIC assays for ampicillin were determined without the addition of IPTG. For additional details see Figures S2 and S3.aMedian value across three replicates (see Table S3 for replicate measurements).bThe error ranges for TEM-1 and mutants R164S and R164S/G238S were determined from two independent measurements with two different protein preparations; error ranges for the remaining variant are estimated to be within the same range.