Linked Life Data

8424794

Source:http://linkedlifedata.com/resource/pubmed/id/8424794

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1993-2-23
pubmed:abstractText
The isomeric compositions of the heptacarboxylic, hexacarboxylic and pentacarboxylic porphyrinogens formed by incubation of porphobilinogen with human red-cell haemolysates have been analysed and compared with those derived from incubation with chemically prepared uroporphyrinogen III as substrate. The results indicated that when supplied with an excess (3.7 microM) of exogenous uroporphyrinogen III, uroporphyrinogen decarboxylase utilized the substrate at random and a mixture of isomers was produced; whereas with uroporphyrinogen III generated enzymically from porphobilinogen as substrate a clockwise decarboxylation sequence was observed, resulting in the formation of intermediates mainly with the ring-D, rings-AD and rings-ABD acetate groups decarboxylated. Using [14C]uroporphyrinogen III as substrate at low concentrations (0.01-0.5 microM) also led to preferential decarboxylation of the ring-D acetate group. It was concluded that the order of uroporphyrinogen III decarboxylation is substrate-concentration-dependent, and under normal physiological conditions enzymic decarboxylation is most probably orderly and clockwise, starting at the ring-D acetate group.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
289 ( Pt 2)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
529-32
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Order of uroporphyrinogen III decarboxylation on incubation of porphobilinogen and uroporphyrinogen III with erythrocyte uroporphyrinogen decarboxylase.
pubmed:affiliation
MRC Toxicology Unit, Medical Research Council Laboratories, Carshalton, Surrey, U.K.
pubmed:publicationType
Journal Article