TABLE 2.

Quinolone susceptibility as a function of temperature in strains with varying SOS response regulation

E. coli strain and plasmid	Ciprofloxacin MIC (μg/ml) ata:
	21°C	30°C	37°C	43°C
GW1000 (lexA+recA441)	0.0005	0.001	0.002	0.004
pMG298 (qnrB1)	0.004	0.012	0.023	0.023
pMG301 (qnrB2)	0.003	0.012	0.012	0.023
pMG317 (qnrB3)	0.094	0.125	0.125	0.19
pMG320 (qnrB5)	0.023	0.032	0.047	0.094
pMG252 (qnrA1)	0.023	0.032	0.047	0.064
pMG306 (qnrS1)	0.064	0.094	0.125	0.125
J53 (lexA+recA+)	0.004	0.008	0.012	0.023
pMG298 (qnrB1)	0.19	0.38	0.38	0.38
pMG252 (qnrA1)	0.19	0.38	0.38	0.38

^aMeasured by Etest on Mueller-Hinton agar plates at the indicated temperatures except for R⁻ GW1000 and J53, for which MICs were performed by agar dilution. Determinations were repeated at least twice.