Send to:

Choose Destination
See comment in PubMed Commons below
Biochem J. 1993 Aug 1;293 ( Pt 3):703-12.

Purification and properties of the uroporphyrinogen decarboxylase from Rhodobacter sphaeroides.

Author information

  • 1School of Biological Sciences, Queen Mary and Westfield College, University of London, U.K.


Uroporphyrinogen decarboxylase (EC was purified 600-fold from Rhodobacter sphaeroides grown anaerobically in the light. The enzyme, under both denaturing and non-denaturing conditions, is a monomer of M(r) 41,000. The Km values are 1.8 microM and 6.0 microM for the conversion of uroporphyrinogen I and III to coproporphyrinogen I and III respectively. The enzyme is susceptible to inhibition by both uroporphyrinogen and uroporphyrin. The pH optimum is 6.8 and the isoelectric point is 4.4. The importance of cysteine and arginine residues is implicated from studies with inhibitors. The sequence of the first 29 amino acids of the N-terminus shows a high degree of similarity to the primary structures of other uroporphyrinogen decarboxylases. Studies on the order of decarboxylation of the four acetic acid side chains of uroporphyrinogen III suggest that at high substrate levels a random route is preferred.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Portland Press Icon for PubMed Central
    Loading ...
    Write to the Help Desk