porphobilinogen


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porphobilinogen

 [por″fo-bĭ-lin´o-jen]
an intermediary product in the biosynthesis of heme.

por·pho·bi·lin·o·gen (PBG),

(pōr'fō-bī-lin'ō-jen),
A porphyrin precursor of porphyrinogens, porphyrins, and heme; found in the urine in large quantities in cases of acute or congenital porphyria.

porphobilinogen

/por·pho·bi·lin·o·gen/ (por″fo-bĭ-lin´ah-jin) an intermediary product in the biosynthesis of heme; it is produced in excess and excreted in the urine in acute intermittent porphyria.

porphobilinogen

[pôr′fōbilin′əjən]
a chromogen substance that is an intermediate in the biosynthesis of heme and porphyrins. It appears in the urine of people with porphyria, representing an error of metabolism. See also heme, porphyria.

por·pho·bi·lin·o·gen

(PBG) (pōr'fō-bī-lin'ŏ-jen)
A porphyrin precursor of porphyrinogens, porphyrins, and heme; found in the urine in large quantities in cases of acute or congenital porphyria.

porphobilinogen

an intermediary product in the biosynthesis of heme. Not detectable in normal animals.

porphobilinogen deaminase
an enzyme involved in the condensation of porphobilinogen. Now called uroporphyrinogen I synthetase.
References in periodicals archive ?
Estimation and application of biological variation of urinary delta-aminolevulinic acid and porphobilinogen in healthy individuals and in patients with acute intermittent porphyria.
Erythrocyte porphobilinogen synthase activity as an indicator of lead exposure in children.
Allosteric inhibition of human lymphoblast and purified porphobilinogen deaminase by protoporphyrinogen and coproporphyrinogen: a possible mechanism for the acute attack of variegate porphyria.
The ALAD gene codes for the enzyme [delta]-aminolevulinic acid dehydratase (ALAD), which catalyzes the second step of heme synthesis involving the condensation of two molecules of aminolevulinic acid (ALA) to form porphobilinogen.
A suspicion of acute intermittent porphyria (AIP) was confirmed when a markedly elevated porphyrin level was detected in her blood and urine (urinary aminolaevulanic acid 1 521 ([micro]mol/10 mmol creatinine, normal <45; urinary porphobilinogen 1 426 ([micro]mol/10 mmol creatinine, normal <16, with a positive plasma peak at 619 nm).
The affinity of human erythrocyte porphobilinogen synthase for Zn2+ and Pb2+.
With the exception of [delta]-aminolevulinic acid dehydratase deficiency, which is very rare, acute porphyrias that present with neurovisceral complaints (acute intermittent porphyria, hereditary coproporhyria, and variegate porphyria) are characterized by large increases in urine porphobilinogen.
These include aminolevulinate (ALA) dehydratase, porphobilinogen deaminase (hydroxymethylbilane synthase), and uroporphyrinogen decarboxylase in spleen and ALA synthase in liver.
Concentrations of the target genes, expressed relative to our housekeeping set [low-abundance housekeeping gene hydroxymethylbilane synthase (HMBS, formerly porphobilinogen deaminase, PBGD), medium-abundance hypoxanthine phosphoribosyltransferase (HPRT), and highabundance [[beta].
Under normal conditions, [delta]-ALA is rapidly dimerized by [delta]-ALA dehydratase (ALAD) to form porphobilinogen.