General aspects of haem synthesis.
D003065:Coenzyme A; D005998:Glycine; D006418:Heme / Q000096:biosynthesis*; D007501:Iron; D007982:Levulinic Acids; D011166:Porphyrins / Q000096:biosynthesis*; D013386:Succinates
D007982:Levulinic Acids; D011166:Porphyrins; D013386:Succinates; D006418:Heme; D007501:Iron; D003065:Coenzyme A; D005998:Glycine