Novel Weapon Evolution and Coincidental Virulence in Environmental Pathogens: A Case Study of Mycobacteria and Buruli ulcer

Mark Eric Benbow

Acceder au replay sur Youtube : https://studio.youtube.com/video/mFCEaMZcaZA/edit

Understanding and controlling emerging infectious diseases before they reach epidemic proportions is important for preventing devastating effects on human health, promoting animal welfare, and improving species conservation. Buruli ulcer disease is a chronic, debilitating infection that destroys skin, soft tissues, and bone, and has been reported from over 30 countries. Disease is caused by Mycobacterium ulcerans, a pathogen closely related to those that cause tuberculosis and leprosy, and the toxin responsible for infection is mycolactone. Transmission of M. ulcerans remains unresolved and there is uncertainty in ecological reservoirs for replication and mechanisms that allow it to persist and disperse in the environment. In this presentation, I discuss a hypothesis that M. ulcerans evolved to produce a novel molecular weapon, mycolactone, that allows it to persist and disperse in environments with human activity and disturbance. Mycolactone is hypothesized to have initially evolved to facilitate mycobacterial colonization and persistence in complex microbial consortia of environmental hosts and reservoirs, but also has a functional role in vertebrate pathogenesis: an attribute that aligns with the Coincidence of Virulence Hypothesis. Discovering and describing new interactions among disease-causing organisms and their environments provide insight into the basic understanding of how diseases emerge and spread.

Department of Entomology, Michigan State University, USA

benbow@msu.edu

Recent publications:

Larson, CE, JL Pechal, BS Gerig, DT Chaloner, GA Lamberti, ME Benbow. 2020. Microbial community response to a novel salmon resource subsidy. Frontiers in Ecology and Evolution 7:505.

Pileggi, SM, HR Jordan, JA Clennon, E Whitney, ME Benbow, RW Merritt, MD McIntosh, RK Kimbirauskus, PLC Small, D Boakye, C Quaye, J Qi, L Campbell, J Gronseth, E Ampadu, W Opare, LA Waller. 2017. Landscape and environmental influences on Mycobacterium ulcerans among aquatic sites in Ghana. PLoS ONE: e0176375

Benbow, ME, RK Kimbirauskus, MD McIntosh, HR Williamson, C Quaye, D Boakye, PLC Small, RW Merritt. 2014. Aquatic macroinvertebrate assemblages of Ghana, West Africa: understanding the ecology of Buruli ulcer disease. EcoHealth 11(2):168-183.