FIG. 2.

Clonality test by PFGE restriction patterns of 15 tetracycline-resistant, M-nontypeable S. pyogenes strains and typing by comparison with the patterns of 11 strains of seven prevalent M types (11 pulsotypes). Chromosomal DNA was digested with SmaI. Lanes 1, 4, 5, 6, 7, 13, 16, 17, 19, and 22 to 27, nontypeable strains; lanes 2, 8, 9, and 12, M11 strains (three pulsotypes); lane 3, an M19 strain; lanes 10 and 18, PT2233 strains (two pulsotypes); lane 11, a PT2110 strain; lane 14, an M59 strain; lane 15, an M6 strain; lane 20, a PT2841 strain; lanes 21 and 28, incompletely digested DNA from an M60 and a nontypeable strain, respectively.