Community Diversity and Functional Capabilities of Benzene­‐Degrading Enrichment Cultures

Benzene is prevalent, toxic, and persistent in anaerobic environments. Anaerobic benzene degradation has been proven, but is not well understood. The goals of this research were to determine the community composition of anaerobic nitrate-reducing benzene-degrading enrichments and propose likely metabolic roles of organisms present. Highly diverse communities were present in the enrichments, with multiple organisms capable of carrying out similar roles. A metagenome assembly was generated from a nitrate-reducing, benzene- degrading enrichment culture. Further evidence for fermenting Peptococcaceae as the initiator of benzene degradation was established. The potential for benzene degradation to be linked to other terminal electron acceptors (i.e., CO2) was confirmed, further supporting that the initial benzene degradation steps are carried out in a fermenting syntroph. An understanding of the functions of different organisms can inform culturing techniques to increase culture growth and benzene degradation rates. Genes present in the metagenome could be used as biomarkers for benzene degradation.M.A.S