9021 (PbgD) hemCThalassiosira pseudonana
GO:0004418 GO:0006779 -
hydroxymethylbilane synthase activity
Catalysis of the reaction: H(2)O + 4 porphobilinogen = hydroxymethylbilane + 4 NH(4)(+).
porphyrin-containing compound biosynthetic process
The chemical reactions and pathways resulting in the formation of any member of a large group of derivatives or analogs of porphyrin. Porphyrin consists of a ring of four pyrrole nuclei linked each to the next at their alpha positions through a methine group.