title: Searching for links in the biotic characteristics and abiotic parameters of nine different biogas plants.
abstract: To find links between the biotic characteristics and abiotic process parameters in anaerobic digestion systems, the microbial communities of nine full-scale biogas plants in South Tyrol (Italy) and Vorarlberg (Austria) were investigated using molecular techniques and the physical and chemical properties were monitored. DNA from sludge samples was subjected to microarray hybridization with the ANAEROCHIP microarray and results indicated that sludge samples grouped into two main clusters, dominated either by Methanosarcina or by Methanosaeta, both aceticlastic methanogens. Hydrogenotrophic methanogens were hardly detected or if detected, gave low hybridization signals. Results obtained using denaturing gradient gel electrophoresis (DGGE) supported the findings of microarray hybridization. Real-time PCR targeting Methanosarcina and Methanosaeta was conducted to provide quantitative data on the dominating methanogens. Correlation analysis to determine any links between the microbial communities found by microarray analysis, and the physicochemical parameters investigated was conducted. It was shown that the sludge samples dominated by the genus Methanosarcina were positively correlated with higher concentrations of acetate, whereas sludge samples dominated by representatives of the genus Methanosaeta had lower acetate concentrations. No other correlations between biotic characteristics and abiotic parameters were found. Methanogenic communities in each reactor were highly stable and resilient over the whole year.
authors.affiliation: University of Innsbruck, Institute of Microbiology, Technikerstraße 25d, 6020 Innsbruck, Austria. andreas.walter@student.uibk.ac.at
authors.forename: Andreas
authors.initials: A
authors.lastname: Walter
authors.forename: Brigitte A
authors.initials: BA
authors.lastname: Knapp
authors.forename: Theresa
authors.initials: T
authors.lastname: Farbmacher
authors.forename: Christian
authors.initials: C
authors.lastname: Ebner
authors.forename: Heribert
authors.initials: H
authors.lastname: Insam
authors.forename: Ingrid H
authors.initials: IH
authors.lastname: Franke-Whittle
mesh_terms: D000085:Acetates / Q000032:analysis; D000693:Anaerobiosis; D001317:Austria; D056804:Biofuels / Q000382:microbiology*; D058448:Biota; D058645:Denaturing Gradient Gel Electrophoresis; D007218:Industrial Microbiology; D007558:Italy; D054892:Metagenome; D017020:Methanosarcina / Q000235:genetics / Q000302:isolation & purification; D019640:Methanosarcinales / Q000235:genetics / Q000302:isolation & purification; D046228:Microarray Analysis; D060888:Real-Time Polymerase Chain Reaction; D012722:Sewage / Q000737:chemistry / Q000382:microbiology*
chemical_list: D000085:Acetates; D056804:Biofuels; D012722:Sewage