Heme Metabolism Flashcards
What are the two starting materials of heme metabolism
Glycine and succinyl CoA
Where does heme metabolism start
Mitochondria
What is the limiting reaction catalysed by
¿-ALA synthase
What serves as a coenzyme for ALA synthase
Pyridoxine phosphate(PLP)
How many molecules of ALA condense in the cytosol
2
Which enzyme is zinc containing and is invited by lead, particularly.
ALA Dehydratase
What is the first pathway intermediate that has a pyrrole ring
Porphobilinogen
What does the condensation of four porphobilinigen(PBG) form? And what enzyme catalyses it
Hydroxymethylbilane
Catalysed by: porphobilinogen deaminase
What’s is protoporphrinogen IX oxidised to
Porphyrinogen IX
What catalyses the final step in hen synthesis
Ferrochelatase
Which step involves the incorporation of ferrous iron
Step from porphyrinigen to heme
What acts both as a repressor and inhibitor of ALA synthase
Heme
Hematin
Which two enzymes are einhiyed by lead
ALA dehydratase
Ferrochelatase
What does hemin inhibit
ALA Synthase
What are epossible triggers of porphyrias
Alcohol
Smoking
Lead poisoning or iron
Hiv
Eating disorders, stress, sunlight
