Figure 5.

ALA treatment rescues synthetase function of HCCS mutants with heme binding defects. Recombinant GST-HCCS variants were coexpressed with cytochrome c in Δccm E. coli either in the presence (gray bars) or absence of ALA (black bars). Cells were lysed with BPER reagent and protein extracts were resolved by SDS-PAGE and transferred to nitrocellulose. Released cytochrome c was detected by heme stain and signal intensity was quantified by densitometry and plotted in GraphPad Prism. Data shown represent the average amount of cytochrome c released by each mutant relative to the level released by WT in the absence of ALA ± SEM, n = 3.