Open AccessStudies on the Mechanism and Stereospecificity of the Urocanase Reaction
Author(s) -
Kaeppeli Franz,
Rétey Jänos
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01609.x
Subject(s) - propionate , chemistry , stereospecificity , pseudomonas putida , double bond , deuterium , succinic acid , medicinal chemistry , stereochemistry , photochemistry , organic chemistry , catalysis , enzyme , physics , quantum mechanics
1 Nuclear‐magnetic‐resonance spectroscopy was used to follow the course of the urocanase reaction. It was shown that 3‐(4′‐hydroxyimidazol‐5′‐yl)‐propionate is the true enzymic product and that it spontaneously tautomerises to recemic 3‐(imidazol‐4′‐one‐5′‐yl)‐propionate. 2 Conversion of urocanate in deuterium oxide by a crude‐enzyme preparation from Pseudomonas putida led to a product containing two adjacent CH 2 H‐groups. Oxidative degradation of this product afforded optically pur ( RR )‐[ 2 H 2 ]succinic acid. This finding defines the sterochmistry of proton addition to the double bond of urocate.