"Spain, 1944" "The civil war has ended." "Hidden in the mountains, armed groups continue fighting the new fascist regime, which struggles to put them down." "They say that a long, long time ago, in the Underground Realm – where neither deceit nor sorrow exists – lived a Princess who dreamt of the human world." "She dreamt of the blue sky, soft breeze, and shining sun." "One day... eluding all oversight, the Princess ran away." "Once on the surface, the light of the sun blinded her and erased from her memory any trace of the past." "The Princess forgot who she was..." "where she came from... her body suffered cold, sickness, and pain, and with the passing of the years... she died." "Nevertheless, her father, the King, knew thatGene acquisition, duplication and metabolic specification: the evolution of fungal methylisocitrate lyases.
Gene duplication represents an evolutionary mechanism for expanding metabolic potential. Here we analysed the evolutionary relatedness of isocitrate and methylisocitrate lyases, which are key enzymes of the glyoxylate and methylcitrate cycle respectively. Phylogenetic analyses imply that ancient eukaryotes acquired an isocitrate lyase gene from a prokaryotic source, but it was lost in some eukaryotic lineages. However, protists, oomycetes and most fungi maintained this gene and successfully integrated the corresponding enzyme into the glyoxylate cycle. A second gene, encoding a highly related enzyme, is present in fungi, but absent from other eukaryotes. This methylisocitrate lyase is specifically involved in propionyl-CoA degradation via the methylcitrate cycle. Although bacteria possess methylisocitrate lyases with a structural fold similar to that of