Figure 1.

Effect of the redD inactivation on morphological differentiation of S. coelicolor. (a) Pictures of R2YE plates inoculated with S. coelicolor M145 (WT, wild-type) and its redD mutant M510. Note the precocious appearance of white-pigmented aerial hyphae. (b) Scanning electron micrographs showing precocious sporulation of the S. coelicolor redD null mutant. In (a,b) (48 h) we can see in the WT the very first aerial hyphae emerging from the dense network of vegetative filaments while in strain M510 (∆redD; c,d) many aerial hyphae have already been produced with occasionally fully matured spore chains (d). In (e,f) (72 h) the redD mutant has fully differentiated into mature spore chains whereas the WT only displays erect aerial hyphae. Bars = 10 µm (a,c); = 3 µm (b,d); = 5 µm (e,f).