EC Number   |
Reaction |
Reference |
|---|
    1.3.98.3 | coproporphyrinogen III + 2 S-adenosyl-L-methionine = protoporphyrinogen IX + 2 CO2 + 2 L-methionine + 2 5'-deoxyadenosine |
catalytic, radical mechanism |
656073 |
| 1.3.98.3 | coproporphyrinogen III + 2 S-adenosyl-L-methionine = protoporphyrinogen IX + 2 CO2 + 2 L-methionine + 2 5'-deoxyadenosine |
conversion of coproporphyrinogen III to protoporphyrinogen IX via the reaction intermediate harderoporphyrinogen. HemN contains a catalytically essential [4Fe-4S] cluster that transfers an electron to bound S-adenosyl-L-methionine, thereby producing methionine and a 5'-deoxyadenosyl radical. This radical then abstracts a hydrogen atom from the beta-carbon of the substrate propionate side chain, resulting in the formation of a coproporphyrinogenyl radical, overview |
711348 |
| 1.3.98.3 | coproporphyrinogen III + 2 S-adenosyl-L-methionine = protoporphyrinogen IX + 2 CO2 + 2 L-methionine + 2 5'-deoxyadenosine |
mechanism |
655340 |
| 1.3.98.3 | coproporphyrinogen III + 2 S-adenosyl-L-methionine = protoporphyrinogen IX + 2 CO2 + 2 L-methionine + 2 5'-deoxyadenosine |
this enzyme differs from EC 1.3.3.3, coproporphyrinogen oxidase, by using S-adenosyl-L-methionine, AdoMet, instead of oxygen as oxidant, it occurs mainly in bacteria, whereas eukaryotes use the oxygen-dependent oxidase, the reaction starts by using an electron from the reduced form of the enzymes [4Fe-4S] cluster to split AdoMet into methionine and the radical 5-deoxyadenosin-5-yl, this radical initiates attack on the 2-carboxyethyl groups, leading to their conversion into vinyl groups. The conversion of .CH-CH2-COO- leading to CH=CH2 + CO2 + e- replaces the electron initially used, reaction mechanism |
658501 |
