Cited by 76Porphyrin Metabolism and DisordersPorphyrin and Phthalocyanine ChemistryNeonatal Health and Biochemistry

Purification and characterization of bovine hepatic uroporphyrinogen decarboxylase

Straka, James G., Kushner, James P.·1983·Biochemistry

Abstract

Uroporphyrinogen decarboxylase (EC 4.1.1.37) has been purified to homogeneity from bovine liver by using isoelectric and salt precipitations, followed by chromatography on DEAE-cellulose, phenyl-Sepharose, hydroxylapatite, and Sephacryl S-200. The purified enzyme is a monomer with an Mr approximately 57 000 and an isoelectric point at pH 4.6. Enzyme activity is optimal in buffers having an ionic strength of approximately 0.1 M and a pH of 6.8. The purified enzyme has a specific activity (expressed as the disappearance of uroporphyrinogen I) of 936 nmol X h-1 X (mg of protein)-1. The purified enzyme catalyzes all four decarboxylation reactions in the conversion of uroporphyrinogen I or III to the corresponding coproporphyrinogen. The rate-limiting step in the physiologically significant conversion of uroporphyrinogen III to coproporphyrinogen III is the decarboxylation of heptacarboxylate III. Kinetic data suggest that the enzyme has at least two noninteracting active sites. At least one sulfhydryl group is required for catalytic activity. The enzyme is inhibited by sulfhydryl-specific reagents and by divalent metal ions including Fe2+, Co2+, Cu2+, Zn2+, and Pb2+. The pattern of accumulation of intermediate (hepta-, hexa-, and pentacarboxylate porphyrinogens) and final (coproporphyrinogen) decarboxylation products is affected by the ratio of substrate (uroporphyrinogen I or III) concentration to enzyme concentration. Under physiologic conditions where the uroporphyrinogen to enzyme ratio is low, the substrate is nearly quantitatively decarboxylated, and the major product is coproporphyrinogen. If the ratio of uroporphyrinogen to enzyme is high, intermediates accumulate, and heptacarboxylate porphyrinogen becomes the major decarboxylation product.(ABSTRACT TRUNCATED AT 250 WORDS)

Integrity signals

Registry

Crossref · 10.1021/bi00289a009

Cites

24 of 24 references verified0 citation errors · 0 not checkable

Statistics

Recomputing p-values needs the paper’s full text.

Claims the paper makes

We couldn’t retrieve this paper’s full text, so its claims and self-check weren’t run. The registry and citation checks still apply.

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Uroporphyrinogen decarboxylase (UROD) catalyzes decarboxylation of all four acetate side chains of uroporphyrinogen III to methyl groups.

    “Uroporphyrinogen decarboxylase (UROD) catalyzes decarboxylation of all four acetate side chains of uroporphyrinogen III to methyl groups [17].”

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Straka, J. G., & Kushner, J. P.
Venue
Biochemistry
Published
1983-09-27
Volume
22
Issue
20
Pages
4664-4672
ISSN
  • 0006-2960 (ISSN-L)
  • 1520-4995
OpenAlex
W1991671513
Cited by
76
References
24
Citations by year
2026: 1 · 2017: 1 · 2016: 1 · 2013: 1
FWCI
1.54
Type
journal article
Language
en
Open access
closed
Locations
  • Biochemistry (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Institutes of Health (2s07rr005428-30, 2t32am007115-11)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Porphyrin Metabolism and Disorders
  • Physical Sciences › Materials Science › Materials Chemistry › Porphyrin and Phthalocyanine Chemistry
  • Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Neonatal Health and Biochemistry
Keywords
uroporphyrinogen decarboxylase, enzyme purification, bovine liver, uroporphyrinogen III, porphyrin synthesis, enzyme kinetics, active site, sulfhydryl groups, metal ion inhibition
MeSH terms
Animals, Carboxy-Lyases, Cations, Divalent, Cattle, Kinetics, Liver, Molecular Weight, Osmolar Concentration, Salts, Substrate Specificity, Uroporphyrinogen Decarboxylase

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review