Analysis of Pools of Targeted Salmonella Deletion Mutants Identifies Novel Genes Affecting Fitness during Competitive Infection in Mice
106 cfu of 933 mutants (pool) or a 1∶1 mixture of individual mutants versus wild-type ATCC14028 ΔphoN::kan were injected into 5–6 mice and recovered from spleen one or two days post infection. Statistical significance was determined using a Student's 2-tailed t test, and asterisks indicate that normalized output ratios were significantly statistically different from the equivalent ratio in the inoculum. ** P value of <0.001, * P value of <0.05. Strains marked with (FRT) have undergone FLP-mediated recombination to reduce or eliminate polar effects. A. Confirmation of mutants, identified by ABACUS, in competitive infections in BALB/c mice. ABACUS prediction for selected mutants (black bars) and confirmation data from competitive infections in BALB/c mice (dark blue bars are from spleen, lighter blue are from liver and cecum) of infected animals. B. Complementation of ΔSTM2303::FRT and ΔSTM3121::FRT mutants in trans. The predictions from ABACUS are indicated as black bars. For complementation experiments animals were infected with either a 1∶1 mixture of the mutant bearing pWSK29 vs. ATCC14028 ΔphoN::kan (negative control, blue bars) or the mutant bearing the corresponding complementing gene on pWSK29 vs. the wild-type ATCC14028Δ phoN::kan (complemented, grey bars).