International Symposium on Synthetic Biology in Toulouse, France (Part 1)
Samir Hamadache - November 9, 2018
The European Association of Synthetic Biology Students and Postdocs (EUSynBioS) held their third annual Symposium in Toulouse, France on October 22nd and 23rd. The event, which has previously been held in London, UK and Madrid, Spain, coincided with BioSynSys 2018, the 4th Conference of the French Research Group on Synthetic Biology, and the two meetings were combined.
EUSynBioS invited SynBio Canada, as well as other national & continental synthetic biology associations, to attend the event and introduce our organizations to each other. I had the privilege of attending on behalf of SynBio Canada, thanks in part to an experiential opportunity grant from Western University. This is the first of a series of posts about my experience. Unfortunately, I was unable to attend all the sessions, so I will only be summarizing presentations that I attended.
Cell-free biosensors, artificial tissues, and plug-and-play signal receptors
I arrived from Paris in time to hear Dr. Peter Voyvodic (Centre de Biochimie Structurale, Montpellier, France) speak about using metabolic pathways in cell-free biosensing systems to expand the range of detectable chemicals. Whereas biosensors commonly involve cells expressing chemical-detection genes, Dr. Voyvodic uses cell extracts including DNA constructs designed to sense the presence of chemicals in a solution without any cells. As a proof-of-concept, his team developed systems to sense hippuric acid and cocaine. These compounds are not easy to detect directly, so the team added genes encoding enzymes that convert either molecule into benzoic acid which is more easily detectable. In their system, the benzoic acid activates the expression of a green fluorescent protein. They found that their cells produced stronger signals in shorter times when compared with living biosensors while avoiding the maintenance requirements and constraints of a cell-based system.
Dr. Aurore Dupin demonstrating that signaling and differentiation can be engineered into an arrangement of droplets.
We then heard from Dr. Aurore Dupin, who is using bottom-up synthetic biology to assemble artificial multi-cellular systems at the Technische Universitat Munchen (Munich, Germany). In her lab, compartments made of water droplets containing E. coli cell extract and synthetic gene circuits, are fused together to simulate a multi-cellular tissue. The compartments are separated by membranes with selective pores that allow the diffusion of a fluorescent molecule between the “cells”. Using this system and a variety of gene circuits, Dr. Dupin and her team assembled artificial tissues with spatiotemporal regulation of signaling. This allows for individual compartments within the tissue to “sense” their position relative to one another, similar to the function of maternal effect genes in embryogenesis.
Dr. Jerome Bonnet presented work from his post-doc Hungju Chang and their team at the Centre de Biochimie Structurale (Montpellier, France) where they are developing a modular platform for bacterial signal receptors. The engineering of signal receptors responsive to a wide range of signals is vital for applications including environmental remediation and cell-based therapies. By pairing CadC, a membrane-bound transcription factor from E. coli, with the single-domain antibody VHH from llamas, they built a receptor that binds to caffeine and activates gene expression in response. Single-domain antibodies like VHHs are ideal for their stability and combinatorial libraries, allowing for easy swapping of the ligand-binding domain to detect molecules other than caffeine. The amino acids that hold the two domains together (the “linker”) plays an important role in determining the signal response level, however, it is difficult to identify relationships between linker structure and function. So, the team developed a mutational strategy to build a library of synthetic linkers such that receptor activity can be finely-tuned by choosing the right linker sequence.
SynBio Canada’s counterparts and breakout discussions
The synbio associations then separated from the rest of the symposium for a special session to introduce ourselves to one another and learn about each other’s work. We received presentations from Dr. Christian Boehm (Chair, EUSynBioS), Matt Tarnowski (President, SynBio UK), Dr. Max Mundt (Vice Head, German Association for Synthetic Biology), and Dr. Konstantinos Vavitsas (Communications Officer, SynBio Australasia). I then presented on behalf of SynBio Canada, after which we were joined by Cassandra Barrett (President, Engineering Biology Research Consortium: Student and Post-Doc Association, USA). This session was a great opportunity to establish the foundations of an international consortium, namely the SynBioS Consortium, by discovering our shared visions & challenges and starting a dialogue on collaboration and community building.
In the evening, we had two sets of three parallel breakout sessions, covering “Science Communication”, “Standards in Synthetic Biology”, and the “Opportunities and Challenges of Building an Academic Career on Synbio”. I first attended the Standards in Synthetic Biology session, which was led by Dr. Konstantinos Vavitsas. He facilitated an open discussion with participants expressing perspectives on areas in synbio where standardization may be beneficial and/or detrimental. Some recurring themes were brought up, such as standardizing measurement methodologies and the communication of experimental results. I expressed my own interest in how standardization fits in the context of educational curricula in synthetic biology, seeing as my university is in the early stages of developing undergraduate and graduate programs. At the end of the discussion, Dr. Vavitsas provided a sign-up sheet so that interested participants could continue the conversation after the symposium.
For the second breakout session, I attended Dr. Pablo Ivan Nikel’s session on academic careers in synthetic biology. After presenting briefly about his own career trajectory in metabolic engineering, he opened the floor for questions and group discussion. Predictably, many questions centered on the choice between paths in academia versus industry and other alternatives, as well as the possibilities of combining or switching between such paths. Dr. Nikel emphasized the importance of finding a niche area of interest and skills where a synthetic biologist can set themselves apart and increase their opportunities for success.
At night, the EUSynBioS Symposium attendees took the metro together to a fine restaurant named L’Ô Zen in the heart of Toulouse for dinner and networking.