Figure 5

Lysozyme sensitivity of C. glutamicum strains. (a) C. glutamicum wild-type strain ATCC13869 (open circle), ATCC13869Δpbp1a (closed circle), ATCC13869ΔcspB (closed triangle), ATCC13869ΔcspBΔpbp1a (closed diamond), ATCC13869Δpbp1b (closed square), and ATCC13869ΔcspBΔpbp1b (X) were incubated in LB medium at 30°C. (b) Lysozyme (final concentration 25 μg/ml) was added to the cultures at the time indicated by an arrow. Growth was monitored by measuring OD₆₆₀. The ΔcspBΔpbp1a double mutation considerably increased lysozyme sensitivity compared with either mutation alone or the wild-type strain. The Δpbp1b mutation showed higher lysozyme sensitivity than Δpbp1a mutation, but had no synergistic effect with ΔcspB mutation.