Coproporphyrinogen III oxidase

Coproporphyrinogen III oxidase - Uroporphyrinogen...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Coproporphyrinogen III oxidase The mitochondrial enzyme, coproporphyrinogen III oxidase, catalyzes the next reaction. The substrate is coproporphyrinogen III. The reaction is conversion of the propionic acid groups of rings I and III to vinyl groups. We now have the final substituent pattern of MV MV MP PM (note that "Petrarchan" pattern of the last four substituent groups). The product is protoporphyrinogen IX (pronounce) . (Some naming systems would call this protoporphyrinogen III to preserve the logic of the nomenclature, but "protoporphyrinogen III" is a departure from a time-honored tradition of referring to this and subsequent compounds by the number "IX.")
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Uroporphyrinogen decarboxylase Uroporphyrinogen decarboxylase decarboxylates the acetic acid groups, converting them to methyl groups. • The physiologically significant substrate is uroporphyrinogen III. • The product is coproporphyrinogen III (pronounce) , which is transported back to the mitochondria, where the remainder of heme synthesis occurs. • The substituent pattern in the coproporphyrinogen is MP MP MP PM. • Uroporphyrinogen decarboxylase also acts on uroporphyrinogen I, yielding coproporphyrinogen I. Coproporphyrinogen I has no known function, and its formation is thought to be a blind pathway....
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online