FIG. 1.

Reduced-minus-oxidized difference spectra of cell extracts (soluble proteins obtained after disintegration of cells by sonification) from P. putida P8 and mutant S12. Samples were reduced with a pinch of dithionite and oxidized in the reference cuvette with potassium ferricyanide. (A) P. putida P8 wild type. (B) P. putida S12. The protein concentration was 10 mg ml⁻¹ for P8 and 12 mg ml⁻¹ for S12. OD, optical density.