Faculty-Invited Speaker: Dr. Kim Seed

Dr. Kim Seed from the University of California, Berkeley will be delivering a talk on March 13, 2025 at 10:00 am in the MSL seminar room (MSL 102). This visit has been organized by Dr. Brett Finlay.

If you are unable to attend in person, the talk will be presented in a hybrid format, and we invite you to register at the following Zoom link: https://ubc.zoom.us/meeting/register/1879ItsBTTiPVRNgJ_YH9A

After registering, you will receive a confirmation email with information for joining the meeting.

Talk title: Coevolution of Phage and Bacteria During Disease in Humans

Abstract:

The evolution of all life is shaped by the relentless conflict between hosts and parasites. Viral parasites of bacteria, known as phages, are key components of all ecosystems and profoundly influence the biology of their bacterial hosts. To resist phage predation, bacteria have evolved diverse defense systems, the full breadth of which is only beginning to be realized. In response, phages evolve counter-defenses, fueling a dynamic arms race that remains underexplored in human disease contexts.

The infectious diarrheal disease cholera, caused by Vibrio cholerae, disproportionately affects communities already burdened by conflict, poverty, and natural disasters. According to the WHO, cholera outbreaks were reported in 45 countries in 2023—more than 50% higher than just two years earlier—underscoring the urgent need to understand its epidemiology. Beyond cholera, the rising threat of antibiotic resistance has renewed interest in phages as targeted antibacterial agents, further emphasizing the importance of studying phage-bacteria interactions in clinically relevant settings.

To address these challenges, my lab, in collaboration with international partners, has established a longitudinal clinical surveillance program focused on epidemic V. cholerae and its lytic phages. Using genomic and mechanistic approaches, we have demonstrated that fluctuations in anti-phage mobile genetic elements are a hallmark of epidemic V. cholerae. Our work has uncovered novel phage defense mechanisms driven by parasitic mobile genetic elements and identified phage-encoded counter-adaptations that promote the diversification of these defense systems.

These discoveries provide new insights into the factors shaping V. cholerae population dynamics during epidemics and deepen our understanding of how phages influence microbial communities in both health and disease. More broadly, understanding these evolutionary interactions is essential for harnessing phages to manipulate microbial populations and develop effective therapeutic and prophylactic strategies.