We are interested in understanding the molecular logic by which Nature generates the diversity of biomolecules and applying the acquired knowledge and tools to the problems of biotechnology and medicine. Biomolecular diversity in many levels underlies not only the complexity of biological systems, but the adaptation and evolution of organisms in a new environment. The living organisms, therefore, have developed sophisticated mechanisms to generate and manipulate diverse biomolecules. For example, bacteria and fungi synthesize a vast number of structurally-diverse secondary metabolites (or natural products) by elegantly-organized biosynthetic processes, and mammalian immune system handles enormous number of different antibodies via a multitude of controlled genetic and cellular processes. Our research aims at dissecting various aspects of the generation of biomolecular diversity, and exploiting these Nature’s processes for practical applications.