title: Thermophilic enrichment of microbial communities in the presence of the ionic liquid 1-ethyl-3-methylimidazolium acetate.
abstract: OBJECTIVE
  The aim of the study was to develop an approach to enrich ionic liquid tolerant micro-organisms that efficiently decompose lignocellulose in a thermophilic and high-solids environment.
  
  
  RESULTS
  High-solids incubations were conducted, using compost as an inoculum source, to enrich for thermophilic communities that decompose switchgrass in the presence of the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]). Ionic liquid levels were increased from 0 to 6% on a total weight basis incrementally. Successful enrichment of a community that decomposed lignocellulose at 55°C in the presence of 6% [C2mim][OAc] was achieved, when the [C2mim][OAc] level was increased stepwise from 2% to 4% to 5% to 6%. Pyrosequencing results revealed a shift in the community and a sharp decrease in richness, when thermophilic conditions were applied.
  
  
  CONCLUSIONS
  A community tolerant to a thermophilic, high-solids environment containing 6% [C2mim][OAc] was enriched from compost. Gradually increasing [C2mim][OAc] concentrations allowed the community to adapt to [C2mim][OAc].
  
  
  CONCLUSIONS
  A successful approach to enrich communities that decompose lignocellulose under thermophilic high-solids conditions in the presence of elevated levels of [C2mim][OAc] has been developed. Communities yielded from this approach will provide resources for the discovery of enzymes and metabolic pathways relevant to biomass pretreatment and fuel production.
authors.affiliation: Joint BioEnergy Institute, Emeryville, CA, USA.
authors.forename: A P
authors.initials: AP
authors.lastname: Reddy
authors.forename: C W
authors.initials: CW
authors.lastname: Simmons
authors.forename: J
authors.initials: J
authors.lastname: Claypool
authors.forename: L
authors.initials: L
authors.lastname: Jabusch
authors.forename: H
authors.initials: H
authors.lastname: Burd
authors.forename: M Z
authors.initials: MZ
authors.lastname: Hadi
authors.forename: B A
authors.initials: BA
authors.lastname: Simmons
authors.forename: S W
authors.initials: SW
authors.lastname: Singer
authors.forename: J S
authors.initials: JS
authors.lastname: VanderGheynst
mesh_terms: D001419:Bacteria / Q000145:classification / Q000378:metabolism; D018533:Biomass; D004269:DNA, Bacterial / Q000302:isolation & purification; D006358:Hot Temperature; D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D008031:Lignin / Q000378:metabolism*; D054892:Metagenome; D008897:Panicum / Q000737:chemistry; D017422:Sequence Analysis, DNA; D012987:Soil; D012988:Soil Microbiology
chemical_list: D004269:DNA, Bacterial; D007093:Imidazoles; D052578:Ionic Liquids; D012987:Soil; C036909:lignocellulose; D008031:Lignin; C518739:1-ethyl-3-methylimidazolium