Growth behavior of R. eutropha H16 and various mutants. Group A comprises the wild type H16, H16 ΔH16_A2203, H16 ΔH16_A0384, H16 ΔptsMHI ΔH16_A0384, H16 ΔfrcACB, and H16 ΔnagFEC (Figure 1a). Group B is represented by mutant strains PHB-4, H16 ΔptsMHI, H16 ΔptsM, H16 ΔptsH, H16 ΔptsI, H16 ΔptsH ΔH16_A2203, H16 ΔptsMHI ΔfrcACB, H16 ΔptsMHI ΔnagFEC, HF39 ptsMH::Tn5::mob, and HF39 ptsI::Tn5::mob (Figure 1b). All strains were cultivated under conditions permissive for PHB storage in MSM containing 1.0% (v/v) glycerol as a sole carbon source. Samples were withdrawn in the exponential, early stationary and stationary growth phase to analyze the PHB contents of the cells. After withdrawal of the sample in the early stationary phase, NH4Cl was added to the cultures to a final concentration of 0.05% (w/v, arrows). Experiments were done in duplicate.