title: Functional analysis of an anaerobic m-xylene-degrading enrichment culture using protein-based stable isotope probing.
abstract: A sulfate-reducing consortium maintained for several years in the laboratory with m-xylene as sole source of carbon and energy was characterized by terminal restriction fragment length polymorphism (T-RFLP) fingerprinting of PCR-amplified 16S rRNA genes and stable isotope probing of proteins (Protein-SIP). During growth upon m-xylene or methyl-labeled m-xylene (1,3-dimethyl-(13)C(2)-benzene), a phylotype affiliated to the family Desulfobacteriaceae became most abundant. A second dominant phylotype was affiliated to the phylum Epsilonproteobacteria. In cultures grown with methyl-labeled m-xylene, 331 proteins were identified by LC-MS/MS analysis. These proteins were either not (13)C-labeled (23%) or showed a (13)C-incorporation of 19-22 atom% (13)C (77%), the latter demonstrating that methyl groups of m-xylene were assimilated. (13)C-labeled proteins were involved in anaerobic m-xylene biodegradation, in sulfate reduction, in the Wood-Ljungdahl-pathway, and in general housekeeping functions. Thirty-eight percent of the labeled proteins were affiliated to Deltaproteobacteria. Probably due to a lack of sequence data from Epsilonproteobacteria, only 14 proteins were assigned to this phylum. Our data suggest that m-xylene is assimilated by the Desulfobacteriaceae phylotype, whereas the role of the Epsilonproteobacterium in the consortium remained unclear.
authors.affiliation: Department of Proteomics, UFZ - Helmholtz Centre for Environmental Research, Leipzig, Germany.
authors.forename: Dragana
authors.initials: D
authors.lastname: Bozinovski
authors.forename: Steffi
authors.initials: S
authors.lastname: Herrmann
authors.forename: Hans-Hermann
authors.initials: HH
authors.lastname: Richnow
authors.forename: Martin
authors.initials: M
authors.lastname: von Bergen
authors.forename: Jana
authors.initials: J
authors.lastname: Seifert
authors.forename: Carsten
authors.initials: C
authors.lastname: Vogt
mesh_terms: D000693:Anaerobiosis; D001426:Bacterial Proteins / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002247:Carbon Isotopes; D020564:Deltaproteobacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D020565:Epsilonproteobacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D053719:Tandem Mass Spectrometry; D014992:Xylenes / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002247:Carbon Isotopes; D012336:RNA, Ribosomal, 16S; D014992:Xylenes; C031285:3-xylene