Graduate Students Mini Symposium III-2023

Program

13:15 Tanguy Chotel - AG Erb
"Establishing Chlamydomonas reinhardtii as a prototyping chassis for chloroplast synthetic biology via high throughput part characterization"

Engineering plants to support the ever-growing population and rapidly changing climate conditions requires a platform to quickly prototype genetic designs, as current approaches are too slow to meet the needs for crop improvement. Synthetic biology approaches could accelerate the workflow for developing novel traits and functions for enhanced crop yield. This requires a standardized toolset for building, integrating and expressing complex genetic circuits. Due to the limitations of high-throughput plant engineering we have established the green microalga Chlamydomonas reinhardtii as a chloroplast prototyping chassis. In order to characterize hundreds of novel regulatory parts, we developed a high-throughput workflow relying on new luminescence and fluorescent reporter genes. Our method led to characterizing dozens new UTRs, Intercistronic Expression Elements, synthetic and natural promoters. This approach also led to the screening of promoter libraries, as a first proof of concept for screening genetic libraries within a photosynthetic chassis. This paves the way for more complex engineering of natural and synthetic metabolisms, using Chlamydomonas as a prototyping step to accelerate plant engineering.

13:45 Malay Shah - AG Sourjik

"Characterization of chemotactic responses to nucleosides in E.coli"

Nucleosides are precursors for synthesis of monomeric units of DNA, but bacteria can utilize them as alternative carbon, nitrogen and energy source for growth. It has been shown that mammalian cells such as macrophages are known to secrete these bio-molecules in their extracellular environment as signals for neighboring cells but influence of nucleosides on bacterial growth, and particularly on bacterial motility and chemotaxis has not been explored yet in detail. We used FRET based chemotaxis assay to demonstrate that E. coli can sense both deoxyribonucleosides and ribonucleosides. Further we also found that the response to thymidine and 5-methyluridine is mediated by Tap chemoreceptor.