title: Bioaugmentation of biogas production by a hydrogen-producing bacterium.
abstract: The rate-limiting nature of the hydrogen concentration prevailing in the anaerobic digester has been recognized, but the associated alterations in the microbial community are unknown. In response to the addition of Enterobacter cloacae cells in laboratory anaerobic digesters, the level of biogas production was augmented. Terminal restriction fragment length polymorphism (T-RFLP) and real-time polymerase chain reaction (Real-Time PCR) were used to study the survival of mesophilic hydrogen-producing bacteria and the effects of their presence on the composition of the other members of the bacterial community. E. cloacae proved to maintain a stable cell number and to influence the microbial composition of the system. Bioaugmentation by a single strain added to the natural biogas-producing microbial community was demonstrated. The community underwent pronounced changes as a result of the relatively slight initial shift in the microbiological system, responding sensitively to the alterations in local hydrogen concentration.
authors.affiliation: Department of Biotechnology, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary. Electronic address: acsn@brc.hu.
authors.forename: Norbert
authors.initials: N
authors.lastname: Ács
authors.affiliation: Department of Biotechnology, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary. Electronic address: bagiz@brc.hu.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Bagi
authors.affiliation: Department of Biotechnology, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary; Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary. Electronic address: rakhely@brc.hu.
authors.forename: Gábor
authors.initials: G
authors.lastname: Rákhely
authors.affiliation: Department of Oral Biology and Experimental Dentistry, University of Szeged, Tisza L. krt. 64, H-6720 Szeged, Hungary. Electronic address: minarovits.janos@stoma.szote.u-szeged.hu.
authors.forename: János
authors.initials: J
authors.lastname: Minárovics
authors.affiliation: Department of Oral Biology and Experimental Dentistry, University of Szeged, Tisza L. krt. 64, H-6720 Szeged, Hungary. Electronic address: stoma@stoma.szote.u-szeged.hu.
authors.forename: Katalin
authors.initials: K
authors.lastname: Nagy
authors.affiliation: Department of Biotechnology, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary; Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary; Department of Oral Biology and Experimental Dentistry, University of Szeged, Tisza L. krt. 64, H-6720 Szeged, Hungary. Electronic address: kornel@brc.hu.
authors.forename: Kornél L
authors.initials: KL
authors.lastname: Kovács
mesh_terms: D000693:Anaerobiosis; D001483:Base Sequence; D056804:Biofuels / Q000382:microbiology*; D002849:Chromatography, Gas; D017931:DNA Primers / Q000235:genetics; D016972:Enterobacter cloacae / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D006859:Hydrogen / Q000378:metabolism*; D064307:Microbiota; D008969:Molecular Sequence Data; D012150:Polymorphism, Restriction Fragment Length; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D056804:Biofuels; D017931:DNA Primers; D006859:Hydrogen
keywords: 16S rRNA gene; Bioaugmentation; Biogas; Enterobacter cloacae; Hydrogen production