Figure 5.

Morphology and CcO activity in wt and mutant strains of S. lividans. (a) S. lividans 1326 (wt), the Δsco and the cox: :Apra mutants were grown on R5 and R5 supplemented with 10 μM Cu(II) for 5 days. (b) The top two frames show the growth of the cox::Apra and Δsco mutants on DNA medium and DNA supplemented with 10 μM Cu(II). Drops of 10 μl containing 1000 spores were spotted on the plates and incubated for 48 h. The appearance of the white fluffy aerial mycelium and grey spores demonstrates that a strain is capable of full morphological development. The lower two frames show the in vivo detection of CcO activity with TMPD as substrate. The blue colour is the result of TMPD conversion to indophenol blue by CcO. (c) Morphology and CcO activity of wt and Δsco mutant transformed with empty vector (pHJL401), pHJL401 containing sco under its own promoter (pSco) and pHJL401 expressing the H176A mutant (pH176A) on DNA plates and DNA supplemented with 10 μM Cu(II). (d) CcO activity detected by the TMPD assay and recorded by digital imaging of the plates. The ImageJ software (http://imagej.nih.gov/ij/) was used to calculate average pixel intensities (s.d. varied from 1% to 15%) of the indophenol blue stained mycelium as seen in (b) and (c). After correction for background reading, the data were multiplied by −1 and plotted as arbitrary units against time.