RAD51 and infection: Next, a single representative from these three groupings (no recA induction, complete tolerance: LCV2; no recA induction or type 3 repression with partial tolerance: LCV7; no recA induction or type 3 repression with complete tolerance: LCV10) was tested for infection of host epithelial cells in the presence or absence of d-Ser (Fig. 3 C–E).