Fig. 2.

SpyCEP influences bacterial clearance in soft tissue and systemic spread of S. pyogenes. A. SpyCEP production by S. pyogenes parent strain H292 and mutant cepA strain H575. Western blots were performed on culture supernatants (left panel) and cell wall preparations (right panel). Wild-type SpyCEP was detected as an approximate 160 kDa band in both the supernatant and the cell wall preparation from strain H292. Strain H575 produced an inactive truncated N-terminal SpyCEP fragment of approximately 40 kDa in the culture supernatant, but not the cell wall due to lack of a cell wall anchor motif. B. Expression of SpyCEP by strain H292 enhanced S. pyogenes survival at the site of infection following intramuscular infection of CD1 female mice compared with strain H575 (P = 0.0019; inoculum 2 × 10⁸ cfu). C. Expression of SpyCEP also enhanced spread of S. pyogenes to the regional lymph node (P = 0.0001). n = 10 mice per group in each experiment, representative of two experiments. ND, not detected; cfu, colony-forming units; horizontal line, median.