title: Multiple syntrophic interactions in a terephthalate-degrading methanogenic consortium.
abstract: Terephthalate (TA) is one of the top 50 chemicals produced worldwide. Its production results in a TA-containing wastewater that is treated by anaerobic processes through a poorly understood methanogenic syntrophy. Using metagenomics, we characterized the methanogenic consortium inside a hyper-mesophilic (that is, between mesophilic and thermophilic), TA-degrading bioreactor. We identified genes belonging to dominant Pelotomaculum species presumably involved in TA degradation through decarboxylation, dearomatization, and modified β-oxidation to H(2)/CO(2) and acetate. These intermediates are converted to CH(4)/CO(2) by three novel hyper-mesophilic methanogens. Additional secondary syntrophic interactions were predicted in Thermotogae, Syntrophus and candidate phyla OP5 and WWE1 populations. The OP5 encodes genes capable of anaerobic autotrophic butyrate production and Thermotogae, Syntrophus and WWE1 have the genetic potential to oxidize butyrate to CO(2)/H(2) and acetate. These observations suggest that the TA-degrading consortium consists of additional syntrophic interactions beyond the standard H(2)-producing syntroph-methanogen partnership that may serve to improve community stability.
authors.affiliation: Joint Genome Institute, Lawrence National Berkeley Laboratory, Walnut Creek, CA, USA.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Lykidis
authors.forename: Chia-Lung
authors.initials: CL
authors.lastname: Chen
authors.forename: Susannah G
authors.initials: SG
authors.lastname: Tringe
authors.forename: Alice C
authors.initials: AC
authors.lastname: McHardy
authors.forename: Alex
authors.initials: A
authors.lastname: Copeland
authors.forename: Nikos C
authors.initials: NC
authors.lastname: Kyrpides
authors.forename: Philip
authors.initials: P
authors.lastname: Hugenholtz
authors.forename: Hervé
authors.initials: H
authors.lastname: Macarie
authors.forename: Alejandro
authors.initials: A
authors.lastname: Olmos
authors.forename: Oscar
authors.initials: O
authors.lastname: Monroy
authors.forename: Wen-Tso
authors.initials: WT
authors.lastname: Liu
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D017753:Ecosystem; D019605:Euryarchaeota / Q000235:genetics / Q000378:metabolism; D054892:Metagenome / Q000235:genetics; D008697:Methane / Q000378:metabolism; D010459:Peptococcaceae / Q000378:metabolism; D010795:Phthalic Acids / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D010795:Phthalic Acids; D012336:RNA, Ribosomal, 16S; C011363:terephthalic acid; D008697:Methane