Diverse lineages of human pathogen live on old oaks

Commensalism is a term for one kind of biological relationship between species in which members of one gain benefits while those of the other neither benefit nor are harmed, contrasted with mutualism or parasitism. One obligate commensal is a common human fungal pathogen, the yeast Candida albicans, and the focus of new paper by assistant professor of plant biology Douda Bensasson published in the journal Genetics:

Most humans are inhabited by the yeast Candida albicans at some point. While largely harmless, it is the most common cause of yeast infections. Though previously unclear whether the yeast can live outside of warm-blooded animals, Bensasson et al. report that genetically diverse strains of C. albicans can live on oak trees for prolonged periods. The study of woodland C. albicans could lead to a better understanding of how virulent forms of yeast emerge.

An outside review (subscription required) of the paper describes how Bensasson and colleagues provide a whole genomic sequence information of strains isolated from C. albicans found in oak trees and compared these sequences with the genome sequences of clinical isolates. Surprisingly, each oak strain was more closely related to strains from humans and other animals than to strains from other oaks.

Fascinating work that contributes to better understanding the fundamental origins of virulence and the potential of this particular yeast to cause disease. Congratulations to Bensasson and her team on this featured publication.

Image: Twisted oak, Broom Hill, New Forest (UK) via Wikimedia commons.