31110-56-2Relevant academic research and scientific papers
Direct assay of enzymes in heme biosynthesis for the detection of porphyrias by tandem mass spectrometry. Uroporphyrinogen decarboxylase and coproporphyrinogen III oxidase
Wang, Yuesong,Gatti, Paula,Sadilek, Martin,Scott, C. Ronald,Turecek, Frantisek,Gelb, Michael H.
, p. 2599 - 2605 (2008/09/20)
We report new assays of enzymes uroporphyrinogen decarboxylase (UROD) and coproporphyrinogen III oxidase (CPO) in the heme biosynthetic pathway. The assays were developed for use in clinical diagnostics of inherited disorders porphyria cutanea tarda and hereditary coproporphyria, respectively. Electrospray ionization tandem mass spectrometry is used to monitor the decarboxylation of pentaporphyrinogen I or uroporphyrinogen III catalyzed by UROD and to determine the enzyme activity in human erythrocytes by measuring the production of coproporphyrinogen I or III. The Km value for pentaporphyrinogen I was measured as 0.17 ± 0.03 μM. A mass spectrometric assay was also developed for the two-step decarboxylative oxidation of coproporphyrinogen III to protoporphyrinogen IX catalyzed by CPO in mitochondria from human lymphocytes (Km = 0.066 ± 0.009 μM). The assays show good reproducibility, use simple workup by liquid-liquid extraction of enzymatic products, and employ commercially available substrates and internal standards.
Synthesis of substrate analogs of methyltransferases in the vitamin B12 biosynthetic pathway and characterization of their enzymatic products
Pichon-Santander, Clotilde,Santander, Patricio J.,Scott, A. Ian
, p. 3904 - 3922 (2007/10/03)
The specificity toward substrate analogs of the first two methyltransferases in the vitamin B12 biosynthetic pathway was probed with 15 synthetic porphyrinogens. Several novel methylated chlorins and isobacteriochlorins were isolated and charac
