Hydroxymethylbilane Synthase article 48 porphobilinogen deaminase 46 Support, Non-U.S. Gov't 32 Male 28 nonhuman 28 Liver 26 male 26 Kinetics 24 Ammonia-Lyases 20 Animals 20 Porphobilinogen Synthase 20 enzymology 20 Animal 18 controlled study 18 Human 16 animal experiment 16 animal tissue 16 metabolism 16 porphobilinogen synthase 16 Erythrocytes 14 Female 14 Mice 14 human 14 liver 14 porphyrin 14 rat 14 5-Aminolevulinate Synthetase 12 Adult 12 Hydrogen-Ion Concentration 12