Figure 1

Route of de novo biosynthesis towards IMP. In red are the enzymatic steps associated with the LCA. In green is the enzymatic synthesis towards CAIR. In pink, are the enzymatic steps specifically identified in Archaea associated with the synthesis of AICAR to IMP. In gold are the folate-dependent enzymatic steps. The asterisk shows the second catalytic activity, IMP cyclohydrolase, achieved by PurH. The precursor PRPP is also indicated.