Fluorescence and transmission electron microscopy observations of R. etli stationary phase cells and bacteroids. Strains used are R. etli wild type (A, C and G) and the rel
mutant CMPG8708 (B, D, E, F). Panels A and B are fluorescence microscopic observation of stationary phase cells. Samples were coloured 120 h post inoculation (1/100 inoculated at OD 600 nm 0.4 in TY medium), using the LIVE/DEAD BacLight Bacterial Viability kit. Constrictions in several enlarged rel
mutant cells are indicated with a white arrow. Panels C, D and E are TEM observations of stationary phase bacteria at 5 days after inoculation in TY medium. The arrowhead indicates a constriction site, only observed for some cells in the mutant samples. Panels F and G are TEM observations of bacteroids isolated from the nodules 35 days after inoculation. Bar represents 5 μm (A, B), 1 μm (C, D, G), 0.5 μm (E, F).