B. Finkle, J. C. Lewis, J. Corse
Sep 1, 1962
Citations
0
Influential Citations
64
Citations
Journal
The Journal of biological chemistry
Abstract
SUMMARY 1. A constitutive nonoxidative decarboxylase from Aerobackr species is described whose substrates are cinnamic acids bearing a 4-hydroxy group. p-Coumaric, caffeic, and ferulic acids (4-hydroxy, 3,4-dihydroxy, and 4-hydroxy-3-methoxycinnamic acids, respectively) are attacked in decreasing order of rate by Aerobacter uerogenes NRRL B-2614. ages, suggests that the ring substituents were not altered by the reaction. The presence of a hydroxyl resonance, even though the bands from the reaction product were too weak to determine the number of hydroxy substituents, makes it most likely that the 3,Cdihydroxy structure of the parent acid was retained and that the compound was 3,4-dihydroxystyrene. 2. The products from p-coumaric and caffeic acids were estab- lished as hydroxystyrenes (4-vinylphenol and 4-vinylcatechol) . The products were identified by their characteristic properties and by nuclear magnetic resonance spectra and, in the case of the product from p-coumaric acid, by synthesis. Absorption spectra and the RF values of the hydroxystyrenes in four solvent systems are given. The decarboxylation product from ferulic acid, presumably 2-methoxy-4-vinylphenol, was not specifically characterized. .&Hydroxystyrene and Product from p-Coumaric Acid-Values from the spectrum of the product in acetone are shown in Table III together with those of 4-methoxystyrene. Again the spec- trum of a substituted styrene is immediately apparent. In this case the aromatic methoxyl region could be scanned without solvent interference, and no peaks were observed. The aromatic band is entirely typical of an asymmetric p-disubstituted ben- zene. Unknown product and synthetic 4-hydroxystyrene gave identical spectra. REFERENCES 3. A cell-free extract of the enzyme showed similarity of sub- strate specificity and pH optimum to the cell-bound enzyme. 4. Aspects of the microbial and higher plant occurrence of the enzyme are discussed.