Figure 3. Identification of an SS2 transposon mutant exhibiting an altered anti-phagocytosis phenotype.

(A) ZY05719.74 mutant showed a significant decrease in its anti-phagocytosis phenotype compared to the ZY05719 wild strain (t-test statistical analysis). The apbE gene complement strain CapbE-ZY05719.74 restored the anti-phagocytosis phenotype. (B) The screening results of ZY05719.74 in 24-well plates. BV2 cells were cultured in 24-well plates; SS2 was used to infect cells with MOI = 1:1; after 1 h of incubation, extracellular bacteria was kill by 10 μg/ml penicillin G and 100 μg/ml gentamycin; ddH₂O was added to make cells lysis; 1 ml THB containing 7.5% agar was added to each well; bacterial number should be counted after culturing at 37 °C overnight.