Biosynthesis of Porphyrins 



43 



In 1945 it was found that glycine was the nitrogenous 

 precursor of the porphyrin (Shemin and Rittenberg, 1945, 

 1946). However, it was not estabhshed from these experi- 



SCHj 



6CH3 3CH 



9CH2 

 6CH38CH 



HEM!N 



5CH3 9CH2 eCH2 5CH3 



3CH2 9CH2 



'OCOOH lOCOOH 



PROTOPORPHYRIN IX. 



CH3 C H, 



METHYLETHYLMALEIMIDE 



COOH 

 CH2 

 CH3 C H2 



C*D 



O^^N^^O 



HEMATINIG ACID 



CO2 

 CC /O, 10) 



CH3 CHj 



CH3 c »i CMl__pH2 



HC 



/^U^ 



H ^ • 



CH3 CH2 



CH2 CH, 



COOH CCOH 



MESOPORPHYRIN 



¥ 



CH3 



CHj CH2 



HOi ; OH 



.2-(3)-METHYL-3-(2) 

 ETHYLTARTARIMIDE 



METHYLETHYLMALEIMIDE 



r 



CH3-C0-C00H 



6 4 3 



CH3-CH2-CO— COOH 



9 a — 3 — 2 



V. 



CH3-COOH 



6 4 



+ 

 C02 



CHj-CHj-COOH 

 9 8 3 



-t- 

 CO2 

 2 



CHjNH2 

 6 



CO2 



4 



C02 

 6 



CH3-COOH. 



9 — a 



C02 

 9 



Fig. 2. Outline of haemin degradation. The letters and numbers 

 underneath the carbon atoms designate the positions of these 



atoms in protoporphyrin. 



*The methylethylmaleimide samples were degraded separately as outlined. 



