FIG 4.

Recovery of K. pneumoniae following carbapenem treatment. Following 2 h (A and C) or 24 h (B and D) of treatment, biofilms were placed in fresh medium and allowed to recover for the indicated time periods. Biofilms were then visualized using SEM (A and B) or plated (C and D) to determine cell viability. SEM indicated a majority of cells had recovered normal cell morphology after 2 h in imipenem-treated biofilms, 6 h in meropenem-treated biofilms, and 24 h in doripenem-treated biofilms. In general, although there were morphological differences observed, there were not significant differences in viability in most treated biofilms, with the exception of doripenem-treated biofilm cells. *, P < 0.05.