Isolation and Identification of the Reaction Product of α-Hydroxy-γ-Carboxymuconic ε-Semialdehyde Dehydrogenase 1
- 1 December 1979
- journal article
- research article
- Published by Oxford University Press (OUP) in The Journal of Biochemistry
- Vol. 86 (6) , 1671-1677
- https://doi.org/10.1093/oxfordjournals.jbchem.a132687
Abstract
The reaction product of enzymic dehydrogenation of ar-hydroxy-r-carboxymuconic e-semial-dehyde (HCMS) was isolated. The analytical data (elemental analyses, IR spectra, mass spectra, proton NMR spectra, and UV spectra) showed that the product was not er-hydroxy-7-carboxymuconic acid (HCMA), the expected primary product of HCMS dehydrogenation, but a lactone of HCMA. The structure of the lactone was tentatively determined as a-pyrone-4,6-dicarboxylic acid. HCMS was converted stoichiometrically to the lactone by the purified NAD(P)-linked HCMS dehydrogenase. The lactone was actively metabolized by a cell-free extract prepared from Pseudomonas ochraceae grown on phthalic acid, suggesting that it may be a metabolic intermediate in the bacterial metabolism of protocatechuic acid. Furthermore, a method for the chemical synthesis of the lactone of HCMA is presented and some of its chemical and biochemical properties are described.This publication has 0 references indexed in Scilit: