FIG. 7.
Abnormal septa in amidase mutants. Cultures of E. coli RP77 (ΔamiABC) (marked with an asterisk) and E. coli RP108 (ΔamiABC ΔPBP5) (unmarked) were stained to visualize septal cross-walls. (A and B) Paired representative chains stained with NHS-Oregon Green 488-X to label the outer membrane (A) or with FM4-64 to label the inner membrane (B). (C) Chains of cells producing GFP-FtsI from plasmid pDSW234. Arrows indicate some of the abnormal septa that are visibly misshapen or tilted relative to the longitudinal axes of the chains.