FIG.3.

Complementation of morphological defects by wild-type and hybrid dd-carboxypeptidase PBPs. Overnight cultures of E. coli strains with or without cloned PBP genes were diluted 1:250 into fresh LB broth and grown at 37°C until it reached an A₆₀₀ of 0.2. Cells were collected, prepared for microscopy, and photographed at a magnification of ×1,000. Two representative fields are shown for each strain, and all photographs are at equal magnification. E. coli CS109 is the parental strain; CS604-2 is missing six PBPs but expresses wild-type levels of PBP 5; CS701-1 is missing the same six PBPs as CS604-2 but also carries a deletion of dacA so that it makes no PBP 5. All plasmids were derived from pBAD18-CAM (A, B, and C). Hybrid proteins were produced from the following plasmids (described in Table 1): pPJ5C (D), pAG6 (E), pPJ5D (anchorless PBP 5 [PBP 5 Δ]) (F), pPJ5/6 (G), pPJ5/DacD (H), pPJ5/4 (I), pPJ5/W (J), pPJ5I/6II (K), and pPJ6I/5II (L).