Inhibition of protohaem ferro-lyase by N-substituted porphyrins. Structural requirements for the inhibitory effect.
N-Methyl mesoporphyrin was a powerful inhibitor of protohaem ferro-lyase in vitro, whereas N-ethyl mesoporphyrin and N-methyl coproporphyrin were not and neither was the newly described green pigment produced by giving rats ethylene. This suggests that the size of the substituent at a pyrrole nitrogen and also the number of carboxylic acid side chains of the substituted porphyrin are important for the inhibitory effect. Evidence that N-methyl mesoporphyrin inhibited the enzyme, whereas the ethylene-derived pigment did not, was also obtained in vivo.
D000624:5-Aminolevulinate Synthetase / Q000378:metabolism; D000818:Animals; D003306:Coproporphyrins / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D005294:Ferrochelatase / Q000037:antagonists & inhibitors*; D008099:Liver / Q000378:metabolism; D008190:Lyases / Q000037:antagonists & inhibitors*; D008297:Male; D008652:Mesoporphyrins / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D010860:Pigments, Biological / Q000494:pharmacology; D011166:Porphyrins / Q000494:pharmacology*; D013053:Spectrophotometry; D013329:Structure-Activity Relationship
D003306:Coproporphyrins; D008652:Mesoporphyrins; D010860:Pigments, Biological; D011166:Porphyrins; C028471:N-ethyl mesoporphyrin; C028472:N-methyl coproporphyrin; D000624:5-Aminolevulinate Synthetase; D008190:Lyases; D005294:Ferrochelatase