After earning a marketing degree at the College of William and Mary and working in business for 5 years, Clarissa decided to return to school to become a scientist. She obtained her Ph.D. from the University of Alabama at Birmingham with Aaron Lucius, studying the mechanism of protein disaggregation by ATP-driven enzymes. She then sought to complement her training in protein complex function with training in the state-of-the-art structural biology tool cryo-electron microscopy. Working with Melanie Ohi at the University of Michigan, she began to investigate the structure of the type IV secretion system in Legionella pneumophila, an essential virulence factor in this bacterial pathogen. Her independent laboratory combines these approaches for holistic studies of protein complex structure and function involved in the protein translocation of bacterial pathogenesis.