Figure 2
HPLC analysis of non-covalently bound hemes extracted from membranes of S. oneidensis grown under different O2 and nutrient conditions.
(a) Heme analysis by reversed-phase HPLC and detection at 405 nm. Hemes were extracted from 10 mg of membranes of S. oneidensis grown under different culture conditions: highly aerobic conditions and carbon starvation at the exponential (III) and the stationary (IV) phases; highly aerobic conditions and iron starvation at the stationary phase (V); aerobic conditions and carbon starvation at the stationary phase (VI). Hemes were identified by comparison with the retention times of hemin (I) and heme a extracted from the aa3-type cytochrome c oxidase from bovine heart (II). Retention times for hemin and heme a were 11.7 and 23.9 min, respectively. Insets are zoom-ins of the chromatograms between 22 and 25.5 min. (b) Absorption spectra (photo-diode array) of peaks 1 and 2 from panels II and IV, respectively.
