Figure 3

MGAS5005Δ srv Δ speB biofilm formation under continuous flow conditions. (A-C) Representative flow cell chambers containing 24 h grown cultures under a flow rate of ~ 0.7 mL/min of MGAS5005Δsrv ΔspeB, MGAS5005, and MGAS5005Δsrv, respectively. (A and B) Chambers inoculated with (A) MGAS5005Δsrv ΔspeB or (B) MGAS5005 were filled with dense viscous material indicative of GAS biofilms. (C) MGAS5005Δsrv was unable to form biofilms under flow conditions. Scanning electron microscopy of a 24 h (D) MGAS5005 and (E-G) a MGAS5005Δsrv ΔspeB continuous flow biofilm clearly depicts chains of cocci organized into a 3-dimensional structure encased in a matrix-like material.