Quantitative biotransformation of catechol tocis,cis-muconate

Summary Growth ofNocardia sp. NCIB 10503 on a suitable aromatic substrate acts to induce a stable catechol 1,2-dioxygenase (EC 1.13.1.1. catechol: oxygen 1,2-oxidoreductase). This enzyme can be obtained without significant loss of activity, and free from the subsequent enzyme of the pathway, by simply freeze-drying a crude cell-free extract. The enzyme preparations can then be used to biotransform catechol quantitatively tocis, cis-muconate. Immobilising the enzyme by co-valently attaching it to cyanogen bromide-activated agarose increased its stability without significantly decreasing enzyme efficiency. The use of the immobilised crude enzyme material offers a cheap mode of generating a biocatalyst not only for the production ofcis, cis-muconate but also related substituted products.