Sphere-rod morphogenesis of Escherichia coli.

The morphogenetic capacity of E. coli was studied by converting the rod-shaped cells into spheres and then determining whether these spheres could revert to rods. The morphogenesis of cells was followed by immobilizing them in a viscous Methocel-containing medium. Two different types of spheres were prepared: cells which retained a mechanically intact sacculus, and osmotically sensitive sphaeroplasts lacking a sacculus. The sphaeroplasts were not able to revert to rods although they were able to synthesize a new sacculus. In contrast, spheres which had retained an intact sacculus were able to reshape themselves into rods. The were also able to form new ends at (or near) the sites of the ends on the original rods.