Figure 4.

Comparison of heme and protein levels in the wild type (WT) and hcf222 mutants. Covalently bound heme groups were detected by their peroxidase activity using luminol as a substrate. A, Detection of heme in cytochrome f. The arrow marks the slight shift of the heme signal in hcf222-2. Corresponding levels of the cytochrome f protein were detected with an antibody (panel AB). B, Heme detection in cytochrome b₆ and the corresponding protein accumulation (gel AB). The AtpA subunit of the ATP synthase was used as a loading control. A total of 40 µg of protein (1x) or the indicated dilutions of the wild type was applied to the gel. The mutant lanes contained 40 µg of protein.