Abstract
This review explores the underlying biochemical and genetic principles leading to the formation of hybrid anthraquinones by recombinant anthracycline-producing streptomycetes transformed with genes encoding the early steps in actinorhodin biosynthesis. Experiments indicate that simple aromatic polyketides are probably synthesized using very similar mechanisms, allowing for the interspecies cloning of polyketide synthase genes for the potential production of novel aromatic polyketide structures.