Regulation of Proton Transfer Through Cf0cf1 by Atp Under Photophosphorylation

Abstract

3.2 billion years ago primordial cyanobacteria started to produce molecular oxygen f r o m water through oxygenic, plant-type photosynthesis thereby transforming an essentially anaerobic into a n aerobic biosphere a n d atmosphere, thus forming the roots of all higher f o r m s of life, shaping the earth to w h a t we are used to now. As a logical consequence of the first production of free oxygen the cyanobacteria finally transformed their photosynthetic into a respiratory system with a n aerobic respiratory chain (conversion hypothesis). During the last three decades in my laboratory, respiratory properties of thirty-three species a n d strains of cyanobacteria were investigated. In all cases it was found, i.a. that isolated plasma as well as thylakoid membranes contained a fully functional aa3-type cytochrome-c oxidase very similar to its much better known counterpart in Paracoccus denitrificans, or even the mitochondrial enzyme, in bioenergetic, biochemical and genetic respects which will be discussed in some more detail in the present presentation (see G.A. Peschek, 1996: Biochem. SOC. Trans. 24,729-733, and BBA 1275,27-32).