ACTIVE TRANSPORT OF INORGANIC PHOSPHATE AND MAGNESIUM IONS BY BEEF HEART MITOCHONDRIA

Abstract

Evidence is presented that the binding of inorganic phosphate by intact beef heart mitochondria is a process coupled to electron transfer, and that this translocation of phosphate (e.g., the binding phenomenon) is actually a process that shares one or more intermediate steps with that of oxidative phosphorylation but differs with regard to the final step(s). The occurrence of the binding phenomenon requires an intact mitochondrion and the presence of Mg ions. Evidence is also presented that supports the view that coupled phosphorylation and coupled translocation are two alternative processes competing for the same high-energy intermediate.