Desiree Francis Email & Phone Number

Kitchener, On, Ca

Guelph, Ontario, Canada

As Escarpment Lab's Production and Laboratory Assistant, I had a number of roles within the company, and took on more roles as I gained experience. My primary duties included harvesting yeast slurries from bioreactor tanks using aseptic techniques and completing quality checks on the products to ensure that they were contamination free. These quality checks were completed on intermediate and final products and included streak plating, spread plating, cell counts, qPCR and small scale test ferments. I also contributed to R&D projects, with most of my time being dedicated to the genetic modification of yeast strains using CRISPR. This included primer design, plasmid construction and purification, bacterial transformations and yeast transformations. Sensory testing demonstrated successful genome editing and the development of new potential yeast strains for propagation.

Stuttgart, Baden-Württemberg, Germany

The main focus of my project over the summer was to develop an enzyme linked immunosorbent assay (ELISA) protocol for quantifying the concentration of Shiga toxin produced by Escherichia coli in environmental samples. The toxin used in these experiments was His-tagged StxA2a that was partially purified using a Ni-NTA column and identified using SDS-PAGE. This was used as the unknown samples for Shiga toxin quantification. The protocol was designed using a checkerboard style assay to determine the ideal concentrations of primary and secondary antibodies to be used. The optimization of the assay resulted in a protocol that could quantify the Shiga toxin concentration in sample above 0.02 µg/mL.The second project that I worked on was the deletion of the fliC gene using the phage Lambda Red recombinase method in Escherichia coli. I isolated and purified a Kanamycin resistance cassette from an E. coli DH5α/pKD4 strain and transformed the resistance cassette into competent E. coli cells. This resulted in the deletion of the fliC gene and integration of the resistance cassette into the new strain.

Guelph, Ontario, Canada

As a Microbiology Lab Technician, I was responsible for performing key microbiological tasks that ensured safety and quality of products through meticulous testing and data analysis. My primary responsibilities included microbial identification, data analysis, equipment calibration, contamination investigations, lab supply management and documentation upkeep. An additional part of my role was to complete proficiency testing that was standardized across all BlueTriton facilities. This directly looked at the standard operating procedures of our facility and whether each of the microbiological tasks were being performed to the highest standard. The proficiency test was completed to a high standard, resulting in the facility scoring excellently

Guelph, Ontario, Canada

My project focused on Candida albicans, a pathogenic fungal species, verifying the deletion of putative error-prone polymerase genes. This included troubleshooting polymerase chain reaction (PCR) protocols to achieve proper imaging results. Once the mutant strains were verified, I ran minimum inhibitory concentration assays and MMS spot plate assays to determine phenotypic changes in the mutants in comparison to the control strains.I was honoured to be a co-author on a paper published in npj - Antimicrobials and Resistance (Nature) called "The putative error prone polymerase REV1 mediates DNA damage and drug resistance in Candida albicans".