Fig. 2
Phenotype of the Δcse mutant. Bright-field micrographs of four-day old cultures of wild-type (WT; left), Δcse (right) and Δcse::pBG2089 (g) growing in 3% CO2 in regular BG11 medium (a, b, g) or in BG110 medium lacking combined nitrogen (c and d). Alcian Blue stains (e and f) were used to visualise heterocysts and proheterocysts, indicated by carets, in long filaments