2.2 SQUARE inside PROTEIN p0 inside PROTEIN p1 inside SIMPLE_MOLECULE H_plus_ inside SIMPLE_MOLECULE CO2 inside SIMPLE_MOLECULE Corrinoid inside SIMPLE_MOLECULE Acetyl_minus_CoA inside SIMPLE_MOLECULE Methylcorrinoid inside SIMPLE_MOLECULE Formate STATE_TRANSITION Formate CO2 c5 c1 c0 STATE_TRANSITION Methylcorrinoid Acetyl_minus_CoA c4 c1 c3 c2