Structure of epi-isozizaene synthase from Streptomyces coelicolor A3(2), a platform for new terpenoid cyclization templates

The X-ray crystal structure characterization of recombinant epi-isozizaene synthase (EIZS), a sesquiterpene cyclase from Streptomyces coelicolor A3(2) is described. Comparison of EIZS and D99N EIZS provides insight into the conformational changes required for the substrate binding and catalysis in a bacterial terpenoid cyclase and the binding interactions of benzyltriethylammonium cation (BTAC) which might imitate those of a carbocation intermediate in catalysis.