TABLE 1.

CovRS mutations and in vitro SsE expression of SpeB^A− variants of MGAS2221 isolated from subcutaneous mouse infection^c

Straina	covRS mutation	Mutated CovS or CovR	SpeB production	In vitro SsEb production
1	132TTTCT136 deletion in covS	Truncated CovS	−	+
2	223G to T in covS	Truncated CovS	−	+
3	1166C to A in covS	CovSAla388Asp	−	+
4	481C to T in covS	Truncated CovS	−	+
5	Insertion of ATTTTCTCTGC at nucleotide 99 in covS	Truncated CovS	−	+
6	616A to T in covR	CovRIle205Phe	−	+
7	616A to T in covR	CovRIle205Phe	−	+
8	1166C to A in covS	CovSAla388Asp	−	+
9	1363C to T in covS	Truncated CovS	−	+
10	1363C to T in covS	Truncated CovS	−	+
11	1166C to A in covS	CovSAla388Asp	−	+
12	None	wt	+	−
13	None	wt	+	−
14	wt	wt	+	−

^aStrains 1 through 11 were all SpeB^A− variants detected among 48 randomly chosen colonies isolated from a mouse infected with MGAS2221, and strains 12 and 13 were randomly chosen from 37 SpeB^A+ colonies in the same test. Strain 14 was MGAS2221.

^bThe SsE production status was assigned according to the data shown in Fig. 7.

^cwt, wild type.