TABLE 4.

Characteristics of eight multistep fluoroquinolone-resistant mutants of M. hominis^a

M. hominis PG21 passage	Mutant	MIC (μg/ml)					Mutationb in QRDR of:
		NFX	PFX	OFX	CFX	SFX	GyrA	GyrB	ParC	ParE
Before passage		8	2	0.5	0.2	0.01
After 12 passages in:
CFX	C1	64	32	16	16	0.2	None	None	None	Asp426→Asn
	C6	64	32	16	16	0.5	None	None	None	Asp426→Asn
NFX	N3	128	32	32	32	1	Ser83→Leu	None	None	Asp426→Asn
	N7	128	32	32	32	1	Ser83→Leu	None	None	Asp426→Asn
OFX	O7	128	64	64	64	4	Ser83→Leu	None	Ser80→Ile	None
	O9	128	64	64	64	4	Ser83→Leu	None	Ser80→Ile	None
PFX	P1	128	32	16	4	0.05	None	None	Ser80→Ile	None
	P4	128	32	16	4	0.05	None	None	Ser80→Ile	None

^aFrom reference 2. 

^bM. hominis GyrA, ParC, and ParE residues are numbered in accordance with the E. coli GyrA, ParC, and GyrB coordinates.