Pharmaceuticals are indispensable for human survival, but there has been a long-term inssued bottleneck at both ends of drug development and production, that is, the efficient synthesis and engineering of the carbon scaffold. Structural modification is pivotal for development of natural products-derived drugs (NPD drugs). It is known that about 90% of NPD drugs have been structurally optimized. However, due to the limitation of chemical reactivity, chemical modification is usually only applicable to active functional groups (such as hydroxyl, amino, etc.), and rarely to the scaffold part composed of saturated carbon atoms (inert scaffold). Therefore, the inert carbon scaffold, which accounts for around half of the molecular scaffold, has always been a forbidden area for the development of new drugs. Hence, developing efficient and universal modification approaches to engineer them in natural products is of great significance to the development of NPD drugs. In drug production, chiral chemical catalysts are usually very expensive and difficult to be used in large-scale production, so current pharmaceutical industry still mainly relies on chiral resolution to obtain chiral drugs. This process is uneconomical, unsustainable and easy to form wastes, therefore development of efficient biosynthetic approaches to stereo-specifically making chiral carbon scaffolds is of great significance for industrial production of pharmaceuticals. The research direction of our group is 'biosynthesis of inert molecular scaffolds'. We focus on three important scaffold types, including polyketides, steroids and azacycles which constitute nearly 100,000 natural products and more than 1500 clinical drugs. Our aim is to i) understand the formation of these molecular scaffolds in natural products, and ii) to develop efficient and universal biosynthetic approaches to engineer or synthesis of these scaffolds. With our efforts, we wish to solve this long-standing bottleneck in the drug development and production.