Team:WashU StLouis/St Louis
On June 21st, our team was able to tour Pfizer’s facility to learn about their synthetic drug manufacturing process. Many of their drug compounds are synthesized using E. coli and yeast and are produced in large quantities. To ensure top quality, they conduct their drug manufacturing in a separate building with increased safety measures. The building contains numerous bioreactors of various sizes for different stages of production.
We visited numerous labs, all working with synthetic biology and were able to see the incredibly large amount of bioreactors being used, as well as the microbioreactors that were a fraction of the size of traditional ones. A couple scientists in each lab explained to us the work they were doing from R&D to testing the synthesized compounds to material purification.
Several of our team members met with Dr. Kunkel, who researches virulence in the model plant-pathogen system of Arabidopsis thaliana and Pseudomonas syringae at Washington University. During the meeting, she spoke about the methods of plant-pathogen interaction in A. thailiana and P. syringae, and compared them to interactions that occur between wheat and wheat rust fungi. She gave the example of an effector AvrRpt2, a protease that is injected into cells by type three secretion system, which interferes with the plant’s production of and response to auxin, a plant hormone and does not necessarily cause a hypersensitive response. She also discussed how new effectors are found and methods of interaction are investigated. While P. syringae is a weak pathogen that is rarely an agricultural issue, this system is a very good model for more complex systems that allows other researchers to understand what patterns to look for in more complicated systems.
Our team met with Dr. Shah, a researcher at the Danforth Plant Sciences Center who studies plant defensin proteins, another method of innate plant resistance to fungal pathogens. He compared resistance and defensin proteins, noted the benefits and drawbacks, and discussed how both are being studied as methods of providing durable resistance to pathogen infection. In contrast to resistance proteins, defensin proteins actively attack the fungal pathogen. For instance, some target and damage the plasma membrane of the fungus. Also, one defensin gene can provide broad spectrum resistance to a variety of pathogens and strains, unlike resistance genes, which are typically pathogen-specific, and in some cases, strain-specific. However, in order to provide durable resistance, one or more defensin genes are often combined with resistance genes to reduce the possibility that a pathogen can develop resistance. Defensin proteins have been shown to protect against leaf rust, but have not yet been tested with stem rust.
Prior to our meeting with Dr. Shah, our team had intended to use a polystyrene membrane for our spore trap based on what we had previously read in literature. However, Dr. Shah informed us that any hydrophobic material could be used as a spore trap, so we decided to change the material of our membrane to polyethylene with a lower environmental impact.