Using Network Analysis and Predictive Functional Analysis to Explore the Fluorotelomer Biotransformation Potential of Soil Microbial Communities

Microbial transformation of per- and polyfluoroalkyl
substances
(PFAS), including fluorotelomer-derived PFAS, by native microbial
communities in the environment has been widely documented. However,
few studies have identified the key microorganisms and their roles
during the PFAS biotransformation processes. This study was undertaken
to gain more insight into the structure and function of soil microbial
communities that are relevant to PFAS biotransformation. We collected
16S rRNA gene sequencing data from 8:2 fluorotelomer alcohol and
6:2 fluorotelomer sulfonate biotransformation studies conducted in
soil microcosms under various redox conditions. Through co-occurrence
network analysis, several genera, including Variovorax, Rhodococcus, and Cupriavidus,
were found to likely play important roles in the biotransformation
of fluorotelomers. Additionally, a metagenomic prediction approach
(PICRUSt2) identified functional genes, including 6-oxocyclohex-1-ene-carbonyl-CoA
hydrolase, cyclohexa-1,5-dienecarbonyl-CoA hydratase, and a fluoride-proton
antiporter gene, that may be involved in defluorination. This study
pioneers the application of these bioinformatics tools in the analysis
of PFAS biotransformation-related sequencing data. Our findings serve
as a foundational reference for investigating enzymatic mechanisms
of microbial defluorination that may facilitate the development of
efficient microbial consortia and/or pure microbial strains for PFAS
biotransformation.