Phenotypic screenings assisted by laboratory robots have emerged as a potent approach for assessing numerous candidate strains under diverse conditions, serving the dual purpose of advancing basic research and tailoring cell factories. Utilizing replica plating robots, microbial strains can be systematically arranged as arrays of 96 to 1536 colonies on a single rectangular agar plate, facilitating comprehensive genome-wide comparisons of genetic traits. Genetically encoded fluorescent biosensors have emerged as a powerful tool to support phenotypic screenings of microbes, enabling the analysis of key physiological parameters such as internal pH, oxidative stress, and concentrations of cofactors and metabolites.
One main focus of my research group has been on integrating robot-assisted replica plating with genetically encoded biosensors to gather in-depth insights into microbial physiology and streamline strain engineering. However, the optical analysis of fluorescent sensor signals from colonies grown on solid media presents certain challenges. To enable physiological studies using genetically encoded biosensors in arrayed colonies, we developed in my group new imaging technologies. In my presentation, I will introduce various applications of this technology platform, including its role in engineering promoters and genetic switches for Saccharomyces cerevisiae and Corynebacterium glutamicum, as well as its contribution to identifying novel regulatory targets in the pH-homeostasis of E. coli. In the final segment of my talk, I will discuss the limitations we encountered during the phenotyping of Corynebacterium strains, particularly in the context of valorizing next-generation feedstocks. Lastly, I will describe our recent approach involving information mining from parallel micro-cultivation experiments, aiming to efficiently select the most suitable strain candidate and predict its performance on a larger scale.
In conclusion, my presentation highlights the advancements in high-throughput methods for physiological studies on microorganisms, offering valuable insights into both technological developments and their practical applications in the field.