Fig. 4. Closest family and genera assignments for metagenomic HgcA genes/fragments for metagenomic data sets containing hgcA.

Assignments were made using MEGAN.5, a program that evaluates the taxonomic and functional content of short-read metagenomic data sets. Circle size represents the relative abundance (square root–transformed) of taxonomically assigned hgcA sequence types in each metagenome. The metagenomes are arranged by environment type, as classified in Fig. 2. PCE, polychloroethylene.