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  • Accepted Manuscript: The Source and Evolutionary History of a Microbial Contaminant Identified Through Soil Metagenomic Analysis
Title: The Source and Evolutionary History of a Microbial Contaminant Identified Through Soil Metagenomic Analysis
It is often important to determine the source of a microbial strain. Examples include tracking a bacterium linked to a disease epidemic, contaminating the food supply, or used in bioterrorism. Strain identification and tracking are generally approached by using cultivation-based or relatively nonspecific gene fingerprinting methods. Genomic methods have the ability to distinguish strains, but this approach typically has been restricted to isolates or relatively low-complexity communities. We demonstrate that strain-resolved metagenomics can be applied to extremely complex soil samples. We genotypically defined a soil-associated bacterium and identified it as a contaminant. By linking together snapshots of the bacterial genome over time, it was possible to estimate how long the contaminant had been diverging from a likely source population. The results are congruent with the derivation of the bacterium from a strain isolated in Germany and sequenced a decade ago and highlight the utility of metagenomics in strain tracking.
Authors:
; ; ; ; ;
Editors:
Brown, C. Titus; Newman, Dianne K.
Award ID(s):
1331940
Publication Date:
NSF-PAR ID:
10401599
Journal Name:
mBio
Volume:
8
Issue:
1
ISSN:
2161-2129
Sponsoring Org:
National Science Foundation
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