MANTA Ray: Development of a microbial co-culture system for heterologous protein production in Pseudomonas putida
Industrial production of proteins via the integration of target genes into foreign host organisms is a cornerstone of biotechnological applications, ranging from pharmaceutical production to agricultural biotechnology. The expression of foreign genes often imposes significant stress on the host cell, primarily due to the depletion of reducing equivalents and energy, as well as the competition for limited cellular machinery. To mitigate this enhanced metabolic load, a strategy know as division of labor, inspired by natural microbial consortium can be employed. The biosynthetic pathway and the associated metabolic burden is divided across two co-cultivated bacterial strains.
To this end, a synthetic co-culture consisting of two strains composed of two Pseudomonas putida strains is first designed, established, and characterized. Pseudomonas putida is a versatile, gram-negative soil bacterium known for its robustness, adaptability to diverse environmental conditions, and metabolic flexibility. Through targeted genetic modifications, an interdependence between the two strains is created, to establish states of balanced growth. This intricate population control mechanisms is based on cross-feeding. Within this first part of the project, particular emphasis is placed on understanding and modelling population dynamics over time.
In the second part of the project the performance of this system will be investigated for various complex biosynthetic pathways with associated high metabolic burden. One objective is to use a cellular capacity monitor to investigate the metabolic load per strain. The second objective is to investigate the optimal splitting point in the pathway to maximize overall product yield. In a first attempt flux balance analysis will be employed to predict such a metabolic node.
Guided by model-based analysis, both the division of the pathway and the adjustment of population ratios can be optimized to achieve an efficient distribution of metabolic tasks, leading to improved overall system performance. By tuning the population ratios of the constituent strains, metabolic fluxes can be effectively controlled, providing an additional layer of regulation over biotechnological processes. In the long term, this platform will enable flexible and scalable biosynthesis of diverse products by simply adjusting the genetic modules in each strain.
Project supervisor: M.Sc. Maren Beyer
Project start date: 01.01.2025