part_of ATP biosynthetic pathway ATP biosynthetic process PW:0000035 Those metabolic reactions involved in the synthesis of adenosine triphosphate (ATP). ATP synthesis is coupled to the electron transfer or respiratory chain pathway which generates an electrochemical gradient that drives the phosphorylation of ADP. The coupling of the two pathways is called oxidative phosphorylation. Under certain circumstances however, the two may be uncoupled. pathway oxidative phosphorylation pathway