Oxidative Phosphorylation coupled with Aerobic and Anaerobic Respiration in a Bacterial Cell-free System

Abstract

IT has been presumed that in anaerobic respiration, such as nitrate¹ or sulphate² respiration, formation of some high-energy phosphate is coupled with the process in a similar way to oxidative phosphorylation in aerobic respiration. We have reported³ that, in the whole cell system of Pseudomonas denitrificans, radioactive inorganic phosphate (³²P_i) is incorporated into labile organic phosphates coupled with the denitrification reaction where nitrite plays a part as a terminal electron acceptor in the anaerobic condition. In this communication more direct evidence that phosphorylation is coupled with aerobic (oxygen) and anaerobic (nitrate) respiration in the cell-free system of this bacteria is described.