Pathways to STEM 2025
January 2025
Funded by a grant from the National Science Foundation, and in collaboration with Citrus College, Oak Crest Institute of Science hosted Pathways to STEM undergraduate students in its student incubator.
The students, guided by a team of excellent peer mentors, self organized to explore the biome of the human nasopharynx.
Working under BSL-2 conditions, the students learned microbiological and biochemical methods and were able to isolate important human pathogens.
Participants: Aimelia Reed, Alexa Medel-Barradas, Amanda Garcia, Berenice Rosales, Magaly, Reyes, River Gallegos, Stella Ho, Hayley Martinez, Tessa Pulgar, William Yu
Peer Mentors: Bianca Cerda, Gabriela Negrete, Brandon Koehn, Katherine Maya-Valencia
Isolating and identifying bacterial pathogens from human volunteers
Swabs from the oral cavity were spread on selective media and grown overnight. Individual colonies were transferred to liquid growth media and grown overnight.
Suspensions of the bacterial cultures were adsorbed onto coated specimen grids and immunolabeled with antibodies that bind specifically to known pathogens. Antibodies bound to bacteria were then labeled with protein A coupled to colloidal gold particles (the black dots seen in the images below), and negatively stained for imaging by transmission electron microscopy
Bacteria labeled with Porphyromonas gingivalis antibodies
Bacterium labeled with Staphylococcus aureus antibodies