Biosynthesis of 2-Nor-6-deoxyerythronolide B by Rationally Designed Domain Substitution

-keto group reduction. The apparentuse of each enzyme activity in the PKS only once duringbiosynthesis suggests that novel polyketides can be generatedby genetic manipulation of the individual activities. Further,the modularity of the PKSs has led to the idea that the con-cepts of combinatorial chemistry can be translated into “com-binatorial biosynthesis” through rearrangement of the geneticmodules.