TABLE 1.

MICs for the strains that caused experimental endocarditis

Strain	MIC (μg/ml)
	Levofloxacin	Nafcillin	Penicillin	Rifampin	Vancomycin
S. sanguis M99	2a		<0.1
S. mitis 543	4a		2
S. aureus 1-63	0.5	0.25		<0.5
S. aureus 76	1	>64		<0.5	1

^aResults for the S. sanguis and S. mitis strains were determined in THB. The MICs determined in cation-adjusted MHB plus 2 to 5% lysed horse blood were 0.5 μg/ml for strain M99 and 2 μg/ml for strain 543.