COO Two molecules of 6-aminolevulinate CH2 Porphyrins Succinyl-COA C-S-CoA OoC CH%-Co0 IIn mammals are O CH, CH2 made from Gly Glycin COO CoA-SH m鬯来家 and succiny-CoA COo Four molecules of reactions I and 6 CH ③卜4NH occur in the mitochondria a-Amino-B C=0 ketoadipate the rest in the cytosols CH-NH s-aminolevulinate 4C02 COo synthase(main ⑥卜4CO2 ①CO2 control target for CH3 CH-CH COO heme biosynthesis) CH C=CH Ferrochelatase CH CHa-C-C C-CHa NH HN C=0 亚铁合 CH N C=C-CH=CHa tHeme CH, HC-C C-CH NHa F 8-Aminolevulinate δ-氨基—y-酮戊酸 CHo CH CH? Protoporphyrin IX 原卟Porphyrins In mammals are made from Gly and succinyl-CoA (reactions 1 and 6 occur in the mitochondria, the rest in the cytosols) d-aminolevulinate synthase (main control target for heme biosynthesis) 胆色素原 原卟啉 d-氨基—g-酮戊酸 Heme Ferrochelatase 亚铁螯合酶 Fe2+