Deciphering regulation and antibiotic production in Streptomyces using synthetic biology

Abstract

This thesis investigates how synthetic biology can be used to expand the genetic accessibility of Streptomyces and accelerate natural product discovery. Streptomyces are filamentous soil bacteria with complex developmental life cycles and an exceptional capacity to produce antibiotics and other bioactive metabolites. However, the rise of antimicrobial resistance, the repeated rediscovery of known compounds, and the silent nature of many biosynthetic gene clusters have limited traditional discovery approaches. This work addresses these challenges by developing and applying genetic tools that enable precise regulation, genome engineering, and pathway reconstruction in Streptomyces. A major focus is placed on CRISPR-based technologies, including inducible CRISPR interference for tunable gene repression and genome-wide functional analysis of transcription factors involved in growth, development, and antibiotic production. In addition, CRISPRi-assisted genome editing and modular biosynthetic gene cluster assembly strategies are established to facilitate large-scale genetic manipulation and pathway refactoring. Together, these approaches provide a versatile synthetic biology framework for dissecting Streptomyces biology and activating hidden metabolic potential. The findings presented in this thesis contribute to a deeper understanding of the regulation of antibiotic production and offer new strategies to support the discovery and engineering of valuable natural products.