Process for the preparation of a novel modified dna sequence of the pyruvate de carboxylase gene.

摘要

A process for obtaining a pyruvate decarboxylase by isolation from a producer organism. The pyruvate decarboxylase is capable of forming (R)-(-)-phenylacetylcarbinole (I) in >/=95% enantiomer unit with a product ratio of (I) to 2-hydoxypropiophenone of >/=95%. In addition, the pyruvate decarboxylase has a specific activity with regard to phenylacetylcarbinole formation of >1U/mg. It is the aim of the invention to obtain a pyruvate decarboxylase with improved synthesis capacity concerning the formation of (R)-(-)-phenylacetylcarbinole. The process of the invention developed for this purpose is characterized in that use is made of a producing organism with a gene coding for pyruvate decarboxylase from Zymomonas mobilis, in the DNA sequence of which the tryptophane radical coding codon TGG is replaced at position 1174-1176 by a codon which codes for an amino acid radical with a reduced volume ratio.