FIG 1.

A majority of emm1 GAS strains have a wild-type secreted SpeB protease phenotype. (A) Casein milk plate hydrolysis assays were performed on 3,615 emm1 GAS strains collected in comprehensive population-based studies conducted at 9 geographically disparate sites in North America and Europe. The number of strains with a SpeB-wild-type (red bar) or deficient (blue bar) phenotype is shown. (B) Comparison of secreted SpeB protease activities in strains recovered within overlapping time intervals from patients in Finland with pharyngeal or invasive infections. (C) Whole-genome sequence data were analyzed in order to identify polymorphisms in 21 genes encoding products implicated in secreted SpeB protease activity, including those involved in direct transcriptional regulation (dark green), indirect transcriptional regulation or posttranscriptional processing (light green), secretion (dark brown), posttranslational processing (light brown), or growth phase or environmental signaling (red), as well as speB and its upstream regulatory region (blue). In some SpeB-deficient strains, no likely causative polymorphisms were identified (gray).