Regulation and manipulation of the gene clusters encoding type-I PKSs

Modular polyketide synthases are large, multifunctional enzyme complexes th at are involved in the biosynthesis of important polyketides. Recent studie s have revolutionized our understanding of the linear organization of polyk etide-synthase-gene clusters. They have provided crucial information on the initiation, elongation and termination of polyketide chains, and thus a ra tional basis for the generation of novel compounds, Combinatorial libraries have helped this field to move from a random approach to a more empirical phase, The large number of diverse analogs of antibiotics that are presentl y produced demonstrate the enormous potential of combinatorial biosynthesis .