Table 3.

Combined activity of amino RES 5 and traditional antibiotics against selected Gram-negative bacteria. AB, A. baumannii LMG 01041, ECl, E. cloacae LMG 02783. ECo, E. coli LMG 8224, KE, K. aerogenes LMG 02094, KP, K. pneumoniae LMG 20218, SE, S. enterica LMG 07233.

		Amino RES 5 (µM)				FICI
		0	2	4	8
AB	Erythromycin	8	2	0.5	0.25	0.132
	Novobiocin	2	0.25	0.031	0.008	0.14
	Rifampicin	0.5	0.062	0.004	0.001	0.133
ECl	Erythromycin	32	32	16	16	0.625
	Nalidixic acid	10.66 ± 2.67	2	1.33 ± 0.33	1.33 ± 0.33	0.25
	Novobiocin	26.67 ± 5.33	6.67 ± 1.33	2.67 ± 0.67	1.33 ± 0.33	0.225
	Rifampicin	>32	21.33 ± 5.33	8	2	0.250
ECo	Erythromycin	32	16	2.33 ± 0.88	0.1 ± 0.02	0.286
	Nalidixic acid	8	4	1	0.080.02	0.375
	Novobiocin	42.66 ± 10.66	16	4	0.031	0.343
	Rifampicin	4	1	0.08 ± 0.02	0.05 ± 0.01	0.27
KA	Erythromycin	>32	32	13.33 ± 2.66	2	0.156
	Minocyclin	4	1	0.5	0.5	0.187
	Nalidixic acid	>32	13.33 ± 2.66	2	2	0.093
	Novobiocin	13.33 ± 2.66	4.67 ± 1.76	2.67 ± 0.66	2	0.262
	Rifampicin	21.33 ± 5.33	8	0.5	0.125	0.085
KP	Minocyclin	>32	32	10.66 ± 2.66	1.33 ± 0.33	0.145
	Nalidixic acid	>32	>32	>32	5.33 ± 1.33	0.208
	Rifampicin	32	32	16	0.42 ± 0.08	0.138
SE	Erythromycin	>32	>32	32	16	0.5
	Nalidixic acid	8	6.66 ± 1.33	4	2	0.5
	Polymyxin B	0.25	0.1 ± 0.04	<0.004	<0.004	0.133
	Rifampicin	8	8	2	0.125	0.265

For the FICI calculations, twice the highest concentration tested was used in the cases where the MIC was not reached. The FICI value for the best combination is represented. The concentrations are expressed in µM ± SE.