Fig 4.

Killing activities of doripenem, colistin, and colistin-doripenem against KPC-K. pneumoniae strains, stratified by doripenem MICs (A) and the presence of ompK36 mutations (B). The P values indicate the differences in median time kills by colistin versus doripenem-colistin in combination. (A) Median log₁₀ kills by doripenem, colistin, and doripenem-colistin against KPC-K. pneumoniae strains with MICs of ≤8 μg/ml (upper graph) and >8 μg/ml (lower graph). Note the lower level of kills for strains with MICs of >8 μg/ml at each time point. (B) Median log₁₀ kills by doripenem, colistin, and doripenem-colistin against other mutant/wild-type ompK36 strains (upper graph) and strains with ins aa134-135 GD or IS5 mutations (lower graph). Note the lower level of kills for ins aa134-135 GD or IS5 mutants.