TraA-dependent OM exchange confers protection from inter-strain killing.
A) Labeled M. fulvus (stained red with DiD lipid dye) was mixed at a 1∶1 cell ratio with isogenic labeled DK1622 derivative strains (stained green with CFDA SE) that contain either TraADK1622 (DK8601*) or TraAM. fulvus (DW1470*). After incubation on an agar surface for the indicated times, cells were collected for microscopic examination to determine the ratio of red to green or yellow cells. Between 300 and >1,000 cells were scored for each time point. B) The experiment was carried out as in A, except DK801 was mixed with isogenic DK1622 derivative strains that contained either TraADK1622 (DK8601*) or ΔTraA (DW1467*). Results are representative from multiple experiments.