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.

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.
References in periodicals archive ?
Laboratory data On day 1 of On day 19 after Normal range admission chelation therapy Hemoglobin 9.4g/dL 11.5 g/dL 13.5-17.5 Hematocrit 27.9% 42% 41-53% AST 57 U/L 32 U/L 0-37 U/L ALT 87U/L 40 U/L 0-40 U/L Blood lead level 62.8 g/dL 31 g/dL <40 [micro]g/dL Urine delta-ALA 81.8 mg/L nil <7mg/L/24hr Urine PBG 1.0 mg/L nil <4mg/L/24hr ALT = alanine aminotransferase; AST = aspartate aminotransferase; PBG = porphobilinogen; ALA = aminolevulinic acid.
D-aminolevulinate dehydratase (ALAD), porphobilinogen deaminase (PBGD) and magnesium chelatase (Mg-chelatase) were the key enzymes reported in the chlorophyll biosynthesis in higher plants.
Acute intermittent porphyria in Sweden: Molecular, functional and clinical consequences of some new mutations found in the porphobilinogen deaminase gene.
A qualitative urinalysis of porphobilinogen was performed, which was positive, confirming the diagnosis of acute intermittent porphyria.
For confirmatory diagnosis, porphobilinogen deaminase (PBGD) test was done which was found to be positive.
In the context of an abnormal excretion of porphobilinogen in the urine of three patients, one has to consider the occurrence of true porphyrias.
Two molecules of ALA are converted into porphobilinogen, reaction mediated by porphobilinogen synthase, and 5 other enzymes, 3 cytosolic and 2 mitochondrial, which lead to the formation of PpIX, which is a very efficient photosensitizer.
These tests revealed increased levels of coproporhyrin and porphyrin precursors such as porphobilinogen (PBG) and aminolevulinic acid.
As per porphyria profile Porphobilinogen and delta amino levaleunate was absent in urine.
Thus, N deficiency leads to decreased synthesis of glutamate, reduced ALA porphobilinogen synthesis and, consequently, a decrease in the biosynthesis of chlorophyll, which leads to the development of chlorosis in plants (CHU et al., 2007).
3-5) Test for urinary porphobilinogen was done by the method of Schwartz et al4 and was negative.