Effect of mutation of polar and lateral flagellar genes of A. caviae Sch3N on lateral flagellum expression and swarming motilitya

StrainMutationPolar flagellabLateral flagellabSwimming phenotypecSwarming phenotyped
Wild type
    A. caviae Sch3++++++
Polar flagellar mutants
    AAR269 flaA::Kmr++++
    AAR27 flaB::Kmr+++++
    AAR31 flaA::CmrflaB::Kmr
    AAR150 flaG::Kmr++++++
    AAR59 flaH::Kmr
    AAR8 flaJ::Kmr
Lateral flagellar mutants
    AAR58 lafA1::Kmr++++
    AAR5 lafA2::Kmr++++
    AAR9 lafB::Kmr++
    AAR20 fliU::Kmr++++
    AAR6 lafA1::CmrlafA2::Kmr++
  • a Strains were tested in duplicate in at least two separate experiments, and the wild-type strain, A. caviae Sch3, was included in all experiments.

  • b Flagellum expression was determined by TEM and Western blotting (10).

  • c Swimming was determined as migration from the source of inoculation in LB broth containing 0.3% agar (Oxoid) after 16 to 24 h at 30°C. Symbols: ++, spreading zone ≥7 cm from central point of inoculation; +, spreading zone ≥2 cm but <7 cm from the inoculation point; −, growth at the inoculum site but no movement.

  • d Swarming was determined as surface migration on Eiken agar swarm plates (0.5% agar in Difco nutrient broth) after 16 to 24 h at 30°C. Symbols: ++, surface motility zone ≥8 cm; +, surface motility zone ≥3 cm but <8 cm; or −, growth at the inoculum site but no surface movement.