Prenyltransferase (PT) and terpene cyclase (TC) are key enzymes in the formation of the basic carbon skeleton of terpenoids, which constitute one of the most structurally and stereochemically diverse families of natural products. By using a genome-based approach, I. Abe (University of Tokyo, Japan) and co-workers identified two new chimeric diterpene synthases composed of three domains (α, β, and γ).These are the first enzymes possessing both Type II TC and PT activities . The α domain is responsible for the PT activity, while the βγ domains compose the Type II TC. Additionally, between the α and βγ domains, there is a characteristic linker in which minimal secondary structure is predicted. This linker does not exist in the other characterized three domain (αβγ) terpene synthases. Therefore, both the catalytic activities and protein architecture substantially differentiate these new enzymes from the previously characterized terpene synthases.