Do cyanobacteria contain "mammalian-type" cytochrome oxidase?

The cytochrome content of membranes isolated from seven species of cyanobacteria was investigated in terms of conventional difference spectra, carbon monoxide difference spectra, photoaction spectra and photodissociation spectra, and by extraction of acid-labile heme followed by spectral identification. In addition, the effect of various inhibitors and activators on the oxidation of horse heart cytochrome c by the membrane was studied. Both the spectral features and the properties of the cytochrome oxidase reaction catalysed by the membranes suggested the presence of a terminal oxidase strikingly similar to mitochondrial ferrocytochrome c:oxygen oxidoreductase (EC. 1.9.3.1).