On November 22, 2021, Bridget Moricz successfully defended her thesis titled, "Adhesins of Streptococcus sanguinis that promote infective endocarditis through interactions with platelets”. She is pictured with her mentor Bradley Jones, PhD.
Research
The human microbiome provides nutrients and protection to its host. For the most part these commensal organisms are benefitable, but sometimes if they leave their niche or overgrow the other organisms in the niche, they can cause disease. For example, commensal organisms from the oral cavity can grow on heart valves resulting in infective endocarditis (IE). Identifying factors that promote virulence is crucial to creating preventatives and therapies. My work has focused on identifying and characterizing factors that promote IE.
Streptococcus sanguinis, one of the leading agents that cause of IE, is an oral commensal. High numbers of this bacteria in the oral cavity is associated with good oral health as it is an antagonist against the cavity causing organism, S. mutans. However, if S. sanguinis gets into the blood stream and conditions are right, it can cause IE. Very few S. sanguinis factors that contribute to IE have been identified and even fewer have been characterized My thesis focuses on identifying and characterizing new factors that contribute to IE through interactions with platelets.
In this work, I identified 12 new virulence factors that are important for different parts of IE pathogenesis. In addition, I found that PbrA is a self-cleaving RTX protein that increases platelet interactions. I also discovered PilB, a minor pilin, that is apart of the type IV pili is required for platelet and cell interactions. Both the type IV pili and PbrA are required for virulence. In addition, I have shown that multiple S. sanguinis factors work together to interact with platelets. My work adds to our understanding of how S. sanguinis causes IE.
About Bridget
Born in Metro Detroit, Bridget was raised by her parents Thomas Moricz and Cheryl Stark. As a child, she fell in love with four things: Scooby-doo, mysteries, reading, and helping people. When she grew up, Bridget wanted to join the Mystery Gang and solve mysteries. When that wasn’t an option, she wanted to help people by becoming a cop. After realizing she was accident-prone, Bridget wanted to then go into teaching, then become a CSI tech, then a baker, then a medical examiner, then a bookstore owner, then a scientist.
In high school, she liked most of the subjects, but the most challenging one was science. She credits Mrs. Waeschle’s excitement and boundless love of science for her igniting passion in science. With this new drive, Bridget headed down the road to Lawrence Technological University to study Molecular and Cell Biology and minor in Chemistry. Mr. Green’s Econ class steered her to minor in Economics which mirrored her evolution class. But it wasn’t until she took every lab taught by Dr. Z-V, Dr. Morrissette, and Dr. Timmons that she discovered that she delighted in solving experimental problems in the lab. After working with Dr. Z-V for her senior project, Bridget adapted to troubleshooting and being resilient.
She participated in the NSF Research Experience for Undergraduates in Dr. Chioma Okeoma’s laboratory in the summer of 2015. That summer of studying HIV inhibition by exosomes introduced her to the excitement of problem-solving, research, and volunteering.
In the spring of 2017, she joined Dr. Brad Jones’ lab, where she studied the virulence factors of S. sanguinis. She has enjoyed trying to match wits with the bacteria. She also dabbled in engineering a probiotic to reduce heart disease. During this time, much to the amazement of the lab (and herself), Bridget achieved 100 accident-free days.
Outside of research, Bridget can be found participating in graduate student events (especially if there’s food), doing crossword puzzles, volunteering, and pranking lab-mates. When not in the lab, you can find Bridget and her mismatched socks setting new records in the bowling alley, trying new beers and food at local restaurants, reading, or baking. She enjoys playing board games and hanging out with her friends, especially with her significant other, Eric.