Representation of essential metabolic pathways in different versions of LUCA: glycolysis and gluconeogenesis. The enzyme names are accompanied by COG numbers and gene names (from E. coli unless indicated otherwise: PH, Pyrococcus horikoshii, BS, Bacillus subtilis). Phyletic patterns for all COGs are shown using the species abbreviations listed in the legend to Fig. 5. The COGs appearing in different reconstructed versions of LUCA are color-coded in this figure and Figures 7,8,9,10,11: LUCA0.9, yellow; LUCA1.0, green; LUCA1.5, blue; LUCA2.0 purple; LUCA3.0, red.