At the Magwene Lab in Duke University’s Genetics and Genomics Department, PhD candidate Cullen Roth is studying Cryptococcus neoformans, a pathogenic fungus estimated to effect almost a quarter of a million people, leading to approximately 180,000 mortalities to cryptococcal disease annually. One of C. neoformans’ key traits is its ability to grow and spread at high temperatures, such as human body temperatures, so with that in purpose, the Magwene lab aims to study why some strains of the pathogenic fungi grow well in high temperature and thus are infectious, while others don’t.
In order to study the genetic differences that control this phenotypic variation, hundreds of fungi are analyzed! By utilizing a flatbed scanner placed inside an incubator, images are obtained and later quantified of fungal growth at high temperatures.
One of the key issues with developing this experimental assay was the placement of the plates that hold samples along the flatbed scanner surface. Roth needed a way to hold the plates in place both within and between experiments to increase reproducibility and to insure correct quantification during downstream processing.
With the help of the Co-Lab, and student employees Lucia and Benjamin, Roth prototyped a fixture design to hold both the samples and the calibration equipment in place during and across experiments. Prior to coming to the Co-Lab, Roth had minimal knowledge in design, but throughout the year, he learned how to use adobe illustrator to design projects and the laser cutters on wood and acrylic. The final product is an acrylic fixture that successfully and reliably holds samples in place across experiments. Furthermore, the acrylic is easy to sanitize between experiments, and holds the calibration hardware in place which makes downstream processing of images computationally feasible.
“The Co-Lab’s staff and resources were integral in helping me develop the skills necessary to design and produce the fixtures used in our experiments. In the coming year we aim to have data that helps us answer the question of what genetic differences underlie variation in growth of C. neoformans at high temperatures.”