TABLE 2.

Growth characteristics of S. aureus strains

Strain	Catabolizes acetate	Doubling time (min)	A600a	Pb relative to:		Beta-hemolytic titer	Production ofc:
				NCTC 8325	N315		Alpha-toxin	Protein A
N315	No	29 ± 1	6.88 ± 0.33	ND	ND	0.0 ± 0	No	Yes
NCTC 8325	No	29 ± 2	9.37 ± 0.21	ND	ND	5,120 ± 0	Yes	No
MRSA-252	Yes	27 ± 2	9.09 ± 0.77	0.2239	0.0024	120 ± 57	No	No
MSSA-476	Yes	23 ± 1	15.65 ± 0.44	<0.0001	<0.0001	320 ± 0	Yes	No
COL	Yes	50 ± 3	10.40 ± 0.20	0.0012	<0.0001	834 ± 274	No	Yes
RF122	Yes	28 ± 3	11.77 ± 0.63	0.0006	<0.0001	7,680 ± 3,620	Yes	No
Mu50	Yes	33 ± 2	12.36 ± 0.77	0.0004	0.0001	240 ± 113	No	Yes
MW2	Yes	23 ± 0	12.19 ± 0.47	0.0014	<0.0001	480 ± 226	Yes	Yes

^aGrowth yields were determined after 12 h of growth. Values are the means ± standard deviations for five independent determinations.

^bStatistical significance of the mean A₆₀₀ relative to value that for strain NCTC 8325 or strain N315 by the Student t test. ND, not determined.

^cThe presence of alpha-toxin and protein A was determined by Western immunoblot analysis of culture supernatants after 7 h of growth.