UniFrac – An online tool for comparing microbial community diversity in a phylogenetic context

TLDR

Comparing many microbial communities simultaneously in a phylogenetic context is essential for large‑scale ecological insights, but widespread use is limited by analytical difficulty. The study introduces UniFrac, a web application that enables easy application and interpretation of phylogenetic tests for differences among microbial communities. UniFrac is accessible at http://bmf.colorado.edu/unifrac and demonstrates clustering of multiple environments and testing for significant differences. Applying UniFrac to Columbia River, estuary, and coastal ocean data revealed insights not seen with other techniques, demonstrating its power to uncover new microbial interactions in environmental and medical contexts.

Abstract

Abstract Background Moving beyond pairwise significance tests to compare many microbial communities simultaneously is critical for understanding large-scale trends in microbial ecology and community assembly. Techniques that allow microbial communities to be compared in a phylogenetic context are rapidly gaining acceptance, but the widespread application of these techniques has been hindered by the difficulty of performing the analyses. Results We introduce UniFrac, a web application available at http://bmf.colorado.edu/unifrac , that allows several phylogenetic tests for differences among communities to be easily applied and interpreted. We demonstrate the use of UniFrac to cluster multiple environments, and to test which environments are significantly different. We show that analysis of previously published sequences from the Columbia river, its estuary, and the adjacent coastal ocean using the UniFrac interface provided insights that were not apparent from the initial data analysis, which used other commonly employed techniques to compare the communities. Conclusion UniFrac provides easy access to powerful multivariate techniques for comparing microbial communities in a phylogenetic context. We thus expect that it will provide a completely new picture of many microbial interactions and processes in both environmental and medical contexts.