Fig. 1.

Growth in photoheterotrophic versus phototrophic growth conditions in response to iron nutrition. Cells were grown in the presence (A) and absence (B) of acetate in various concentrations of iron. Cultures lacking acetate were bubbled with air. Various concentrations of iron represented by empty triangles (0.1-μM Fe), filled triangles (0.2-μM Fe), empty circles (1-μM Fe), and filled circles (20-μM Fe). Standard deviation based on biological triplicates. Dotted line indicates cell density at which cells were collected for analysis