TABLE 2.

Isolation of CIP-resistant mutants of V. parahaemolyticus AQ3815 and their susceptibilities to various quinolone antibacterials

Strain	Selection step	Concn (μg/ml) of CIP used for isolation	Isolation frequency	MIC (μg/ml)a
				CIP	ENX	NAD	NOR	OFX	SPX	NAL
AQ3815b	nac	na	na	0.20	0.39	0.39	0.20	0.39	0.39	0.39
VP-M1	1st	0.78	6 × 10−8	0.78	3.13	3.13	0.78	0.78	0.39	12.5
VP-M2	2nd	3.13	4 × 10−7	6.25	25	6.25	25	6.25	3.13	50
VP-M3	3rd	25	6 × 10−8	50	100	25	100	50	12.5	100
VP-M4	4th	50	1 × 10−7	200	100	100	>200	200	50	100

^aENX, enoxacin; NAD, nadifloxacin; NOR, norfloxacin; OFX, ofloxacin; SPX, sparfloxacin; NAL, nalidixic acid. 

^bWild-type strain. 

^cNot applicable.