TABLE 5.

Influence of mexZ on PA5471-dependent antimicrobial resistance

Strain	Relevant genotype	MIC (μg/ml)a
		Ami	Gen	Kan	Neo	Par	Spc	Str	Tob	Ery	Nor	Tet
K767		4	8	128	64	256	512	32	—	512	0.5	16
K2415	ΔmexZ	4	8	128	128	512	1,024	64	—	512	1	16
K2416	ΔmexZ ΔPA5471b	4	8	128	128	512	1,024	64	—	512	1	16

^aAntibiotic abbreviations are defined in Table 3. —, not determined. The loss of PA5471 did not impact the MICs of these agents in K767 (Table 3), and thus the impact of PA5471 loss on the MICs of these agents was not studied here. Agents for which resistance was increased upon loss of mexZ are indicated in bold.

^bIn contrast to the lack of any impact of PA5471 loss on resistance of the MexZ⁻ strain K2415, the loss of PA5471 in the MexZ⁺ strain K767 compromised resistance to all agents listed here, except for neomycin and norfloxacin (Table 3, compare K2418 and K767).