"Ecological opportunity, Evolution, and the Emergence of Flea-borne Plague." (2016)
B. Joseph Hinnebusch, Iman Chouikha, and Yi-Cheng Sun
Abstract
The plague bacillus Yersinia pestis is unique among the pathogenic Enterobacteriaceae in utilizing an arthropod-borne transmission route. Transmission by fleabite is a recent evolutionary adaptation that followed the divergence of Y. pestis from the closely related food- and water-borne enteric pathogen Yersinia pseudotuberculosis. A combination of population genetics, comparative genomics, and investigations of Yersinia-flea interactions have disclosed the important steps in the evolution and emergence of Y. pestis as a flea-borne pathogen. Only a few genetic changes, representing both gene gain by lateral transfer and gene loss by pseudogenization, were fundamental to this process. The emergence of Y. pestis fits evolutionary theories that emphasize ecological opportunity in adaptive diversification and rapid emergence of new species.