Extended Data Fig. 5: Reduction potential of NAD(P)/FAD substitutes influences the size of expanded networks.
From: Environmental boundary conditions for the origin of life converge to an organo-sulfur metabolism
We plotted the size (number of metabolites, y-axis) of expanded networks as a function of reduction potential of NAD(P)/FAD substitutes (x-axis) for different physico-chemical conditions with (a) no fixed carbon or thiols, (b) fixed carbon and no thiols, (c) thiols and no fixed carbon, and (d) both fixed carbon and thiols. (e) We plot the range of physiologically feasible reduction potentials for classes of redox systems potentially relevant for early protometabolic systems, showing that dithiol/disulfide redox systems could potentially have enabled expansion under a variety of conditions.
