Fig 1.
Morphology and motility of 702mot-, WT and 702compl strains.
(A) Observation under dark-field microscopy at ×20 or ×200 magnifications of cultures in liquid EMJH. (B) Spread of bacteria on soft 0.5% agar EMJH plates observed after 10 days of incubation. Identical results were obtained on 0.3% agar plates (S2 Fig). (C) Images taken every 0.1 s during 0.6 s under dark-field microscopy at ×200 magnification.
Table 1.
Mean cell and flagella length as determined by dark-field microscopy, immunofluorescence (IFA) and electron microscopy (TEM).
Fig 2.
Mutation in fliM gene in 702mot- strain.
(A) Genetic locus of fliM gene in L. interrogans. The arrow indicates the localization of the SNP in the 702mot- strain. Gene nomenclature corresponds to the homologs in L. interrogans serovar Copenhageni strain Fiocruz L1-130. (B) fliM nucleotide and corresponding amino acid sequences in mutated and WT strains. The deletion at position 105 of the coding sequence in strain 702mot- induces a stop codon. (C) Detection of FliM and LipL41 by immunoblots. Uncropped gels are presented in S4 Fig.
Fig 3.
Virulence of 702mot-, WT and 702compl strains.
The hamsters were infected intraperitoneally with the three strains. One group of 5 hamsters received 108 leptospires of 702mot- strain, 2 groups of 5 hamsters received 108 or 106 leptospires of WT strain and 2 groups of 10 hamsters received 108 or 106 leptospires of 702compl strain.
Fig 4.
Flagella integrity in 702mot-, WT and 702compl strains.
(A) Immunofluorescence assay using FlaB antibody on methanol permeabilized cells detected by Cy3 coupled secondary antibodies (yellow) and DAPI counterstaining (blue). Merged images are presented. (B and C) Observation of flagella preparations by transmission electron microscopy after negative staining with uranyl acetate at ×4,800 magnification (B) and ×30,000 magnification (C). The arrows point flagellar motors.
Fig 5.
Flagellar protein content in 702mot-, 702compl and WT strains.
(A) Purified flagella analyzed by Coomassie stained SDS-PAGE. (B and C) Detection of FlaA2 and FlaB by immunoblots in (B) purified flagella and (C) whole cell lysates. Uncropped gels are presented in S7 Fig.