Effect of fluoropyruvate on the swelling, phosphorylative activity and respiration of guinea-pig liver mitochondria

Abstract

The spectrum shows, in addition to the visu- ally recorded a-, ,B-and y-bands, a distinct 8-band, which takes the shape of a shoulder in the oxi- dized cytochrome c, and has a sharp maximum in the reduced form.This band has an isosbestic point for the ferriand ferro-forms of cytochrome c near to 340 ml,u which may be useful in the spectro- photometric study of oxidation and reduction of coenzyme I in systems also containing cytochrome c.There is a distinct difference in the so-called 'protein' band between the reduced and oxidized forms of cytochrome c around 280 m,.Since the spectra of the amino acids that absorb in this region (tyrosine, tryptophan and phenylalanine) were probably not affected by the state of oxidation or reduction of the haem, it must be assumed that the difference between the two spectra was due to a relatively large absorption of the haem in this region, which differed in the ferriand ferro-states.