SEM of P. putida KT2440 and some of the P. putida tol mutants. Cells were grown on LB medium, harvested in the exponential phase of growth, and treated for SEM as described in Materials and Methods. (A) Strain KT2440. Magnification, ×15,000. (B) Strain QΩ. Magnification, ×10,000. (C) Strain RΩ. Magnification, ×10,000. (D) Strain AΩ. Magnification, ×10,000. (E) Strain BX. Magnification, ×5,000. (F) Strain DOT-OX2. Magnification, ×7,000.