Figure 1.

The mutant cia6 demonstrated a typical CCM-deficient phenotype. The ability of cia6 to grow photoautotrophically was tested by comparing its growth on minimal plates under high-CO₂ (5% [v/v] CO₂; A) and very-low-CO₂ (0.01% [v/v] CO₂; B) conditions. A, cia6 grew well in high CO₂ compared with its parental strain D66. B, cia6 grew poorly under low-CO₂ conditions, similar to the CCM-deficient mutant cia5. The complemented cia6, cia6-comp, in which the wild-type CIA6 gene was put back into cia6, exhibited a phenotype similar to that of the wild-type D66. [See online article for color version of this figure.]