title: Enumeration and identification of dominant types of sulfate-reducing bacteria in pulp from a paper-recycling plant: a multiphasic approach.
abstract: Multiple independent approaches were applied for monitoring the abundance and identity of sulfate-reducing bacteria (SRB) in pulp of a paper-recycling plant suffering from excessive sulfide emission. The methods applied included most-probable-number (MPN) enumeration of cultivable SRB, rate measurements, FISH and PCR-based retrieval of the functional marker genes dsrA and B (encoding the two major subunits of dissimilatory bisulfite reductase) and 16S rRNA genes. The SRB community was composed of phylogenetically highly different lineages all of low abundance relative to the total microbial community in the pulp, which hampered the applicability of FISH. It was also demonstrated that dsrA- or B-targeted PCR primers commonly used for denaturing gradient gel electrophoresis and real-time PCR analyses were biased. However, using a novel approach combining MPN-PCR and terminal restriction fragment length polymorphism analysis of dsrAB amplicons generated from serially diluted DNA extracts allowed the enumeration and identification of the quantitatively most important members of the SRB community. For fast quantification of SRB in the pulp, the dsrAB-MPN-PCR assay and sulfate reduction rate measurements were found to be most suitable.
authors.affiliation: Department of Biological Sciences, Section for Microbiology, Aarhus University, DK-8000 Aarhus, Denmark.
authors.forename: Kasper Urup
authors.initials: KU
authors.lastname: Kjeldsen
authors.forename: Lone
authors.initials: L
authors.lastname: Tang
authors.forename: Maria Giltoft
authors.initials: MG
authors.lastname: Jørgensen
authors.forename: Kjeld
authors.initials: K
authors.lastname: Ingvorsen
mesh_terms: D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D020459:Genes, rRNA; D050885:Hydrogensulfite Reductase / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D010209:Paper; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D016999:Sulfur-Reducing Bacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D014865:Waste Disposal, Fluid
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D050885:Hydrogensulfite Reductase