Streptomycetes are Gram-positive multicellular soil-dwelling bacteria which are commercially used as natural producers of antibiotics, anticancer agents and immunosuppressants, as well as many... Show moreStreptomycetes are Gram-positive multicellular soil-dwelling bacteria which are commercially used as natural producers of antibiotics, anticancer agents and immunosuppressants, as well as many industrial enzymes (Hopwood 2007). Similarly to fungi, they carry out a complex developmental life cycle, forming highly structured multicellular colonies composed of physiologically distinct hyphae (Miguelez et al. 2000). A major scientific challenge lies in understanding how growth parameters are controlled in response to nutritional conditions, and how this affects the efficiency of production and secretion of proteins and antibiotics. The work presented in this thesis therefore aims to arrive at a better understanding of Streptomyces morphogenesis and development, and how these processes link to productivity. Studies performed include the analysis of several novel coiled-coil proteins and their effect on morphogenesis an d division, as well as fluorescent live imaging to better understand and localize dynamic secretion systems. Cryo-correlative light and electron microscopy, and specifically tomography, was performed to image vegetative cell division and its effect on development within a pellet. Combining the multi-scale information gained, a structured morphological model was created to provide a framework for rational design of Streptomyces sp. and provide a test drive for the fermentation process. Show less
