Afterwards, hydroxymethylbilane is converted to uroporphyrinogen III and catalyzed to coproporphyrinogen III via uroporphyrinogen III cosynthase and uroporphyrinogen decarboxylase, respectively.

之后，羟甲基胆素通过III协同合成酶转化III，再由羧酶催化粪III。

Next, coprophyrinogen III is brought back into the mitochondria and converted into protoporphyrinogen IX by coproporphyrinogen oxidase.

然后，粪Ⅲ被运送回线粒体，并通过粪氧化酶转化IX。

Afterwards, hydroxymethylbilane is converted to Uroporphyrinogen III and catalyzed to coproporphrinogen III, via uroporphyrinogen III co-synphase and uroporphyrinogen decarboxylase respectively.

之后，羟甲基胆色烷转化III，并分别通过Ⅲ共合酶与羧酶催化形成粪Ⅲ。