IL17RA and infection: To test our Tn-seq predictions, we compared the course of ΔwbkF and Δper (LPS O chain biosynthesis) and ΔfadA and ΔfadJ (β-oxidation of fatty acids) with a wild-type B. melitensis strain in wild-type, IL-17RA-/- and asthmatic mice, by counting the CFU 5 and 48 hours post-infection.