(A) Growth of the Escherichia coli strains TB28 (top) and RM349 (ΔftsZ, bottom) containing the unstable plasmid pOU82-Amp-ftsZ streaked on nutrient agar plates in the presence of X-gal. (B) L-form colonies of the E. coli strains RM349 (ΔftsZ, pOU82-Amp-ftsZ, top left), RM350 (ΔmurA, ΔftsZ, pOU82-Amp-ftsZ, pSK122-Cm-murA, top right), RM61 (ΔftsK, pSK122-Cm-ftsK, bottom left), and RM359 (ΔmreBCD, pHM82-Kn-mreBCD) on L-form-supporting medium (MSM) plates in the presence of fosfomycin (FOS) and X-gal, after several repeated streakings on MSM plates in the presence of FOS. (C) Multiplex PCR of the ftsK, murA, ftsZ, and mreC genes from genomic DNA of the E. coli strains RM349 (1, 2), RM350 (3, 4), RM61 (5, 6), and RM359 (7, 8) grown in the walled (1, 3, 5 and 7) or L-form (2, 4, 6 and 8) states obtained from the strains in panel (B). M represents the 100 bp DNA ladder. (D) Growth of the Staphylococcus aureus strain RNpFtsZ-1 (erm-pSPAC-ftsZ, Pinho and Errington, 2003) streaked on MSM plates in the absence (lipid II ON, left) or presence (lipid II OFF, middle and right) of FOS, with (+FtsZ, middle) or without (−FtsZ, left and right) isopropyl β-d-1-thiogalactopyranoside. (E) Growth profiles of Corynebacterium glutamicum in MSM with (L-form state; right, lipid II OFF) or without (walled state; left, lipid II ON) D-cycloserine, and in the absence (red) or presence (blue) of cephalexin.