evolution of porins , sodium extrusion and potassium import , conversion of the facilitated diffusion proteins to active pumps , and the evolution of intermediary metabolism , carbon and nitrogen fixation , and of substrate level phosphorylation , completed the origin of the first negibacterial eubacterium , from which all other cells evolved , and from which they have inherited most of their major catalytic properties -- with the notable exceptions of reverse transcriptase , rna splicing , and methanogenesis , all of which i believe evolved very much later .
C0031715
phosphorylation
C0035379
reverse