Purification and some properties of the enzyme catalyzing the C sub( gamma )-elimination of a diarylpropane-type lignin model from Pseudomonas paucimobilis) TMY1009

A novel enzyme catalyzing the C sub( gamma )-elimination of a diarylpropane-type lignin model, erythro-1,2-bis(4-hydroxy-3-methoxyphenyl)-propane-1,3-diol, was purified from a cell-free extract of Pseudomonas paucimobilis) TMY1009. When the diarylpropane was decomposed by the purified enzyme, equimolar amounts of 1,2-bis(4-hydroxy-3-methoxyphenyl)-ethylene and formaldehyde were produced as reaction products, suggesting that the enzymatic reaction is C sub( gamma )-deformylation accompanied with dehydroxylation at the C sub( alpha )-position. Consequently, this enzyme was designated tentatively as diarylpropane formaldehyde lyase. The optimum pH for the enzyme activity was around 7.5 and the Km value for the diarylpropane was 71 mu M. This enzyme was seemed to be composed of two identical subunits and the molecular weight of the native enzyme was estimated to be 80,000.