FIG 4.
OmrA is not required for stimulation or lipoprotein transfer. (A) A nonmotile but stimulatable recipient (DW1466) was mixed with isogenic nonmotile donors that contain the indicated alleles (DK8601, DW1467, and DW1604 in the first, second, and third panels, respectively). In the far right panel, the stimulatable recipient (Rec) instead contains the omrA mutation (DW1612 mixed with DK8601). Micrographs were taken after 1 day of incubation. (B) (Top) Merged fluorescence micrographs showing that transfer (yellow) of the SSOM-mCherry lipoprotein to a GFP-labeled recipient (DW709) is Tra dependent (DW1478, tra+; DW1479, traA mutant). Bar, 3 μm. (Bottom) Lipoprotein transfer from an isogenic omrA::mini-Tn5 donor (DW1611). To show the transfer unambiguously, the red, green, and merged panels are all shown. Arrows, transfer to a recipient cell.