Table 1

ΔflaB mutants are unable to establish infection in mice by needle inoculationa

Mode of inoculation and relevant genotypeInoculumNo. of mice positive by serology/no. testedNo. of tissues positive/no. examinedNo. of mice infected/no. tested
EarBladderJoint
Subcutaneous injection
    WT5 × 1035/55/55/55/55/5
    ΔflaB#45 × 1030/50/50/50/50/5
    ΔflaB#65 × 1030/50/50/50/50/5
    Complemented flaB+5 × 1030/50/50/50/50/5
    Complemented flaB+1 × 106Not done5/55/55/55/5
    WT1 × 1094/44/44/44/44/4
    ΔflaB#41 × 1094/40/40/40/40/4
    ΔflaB#61 × 1094/40/40/40/40/4
Tail vein injection
    WT5 × 1034/43/44/44/44/4
    ΔflaB#45 × 1034/40/40/40/40/4
    ΔflaB#65 × 1034/40/40/40/40/4
  • a C3H/HeN mice were injected subcutaneously or via tail vein. Infectivity results with RML mice (5 × 103 spirochetes/mouse; 4 mice per strain) were the same as for the C3H/HeN mice but are not included. RML mice were injected via subcutaneous and intraperitoneal routes. Infectivity was determined by reisolation of B. burgdorferi from tissue samples from sacrificed mice. WT, wild type.