Table 1.

Effect of copper on the MIC of ampicillin (µg/mL) against E. coli and E. faecium strains

CuCl2 (mM)	E. coli BW25113*			E. faecium*
	WT (none)	M1 (LDT)	pTRC99aΩ blaTEM116 (β-Lactamase)	M512 (LDT)	D344R (PBP5)
0	8	128	>512	512	32
0.25	8	64	>512	512	32
0.5	8	64	>512	512	32
1	16	8	>512	512	32
2	8	8	>512	4	32
4	16	16	>512	8	64
8	32	32	>512	8	512

The values are medians of five independent experiments.

^*The resistance mechanism of strains is in parenthesis.