The cradle chemistry of life: On the origin of natural products in a pyrite-pulled chemoautotrophic origin of life

Abstract

It is argued that life originated in an autocatalytic carbon dioxide fixation cycle. Specifically, an archaic version of the reductive citrate cycle is discussed. The reducing power for this process is seen as being provided by the formation of pyrite from iron sulfide and hydrogen sulfide. A variety of novel pyrite-pulled redox reactions will be discussed which support this proposal. It is suggested that the mechanism of oxidative pyrite formation gives rise to group activation in the form of thioacids and thioesters and to the formation of carbanions for condensation reactions. As examples of the evolution of biosynthetic pathways the joint origin of fatty and isoprenoid lipids is discussed as well as an archaic version of the tetrapyrrol pathways. © 1993 IUPAC