title: Identity, abundance and ecophysiology of filamentous bacteria belonging to the Bacteroidetes present in activated sludge plants.
abstract: Filamentous members of the Bacteroidetes are commonly observed in activated sludge samples originating from both municipal and industrial wastewater treatment plants (WWTP), where they occasionally can cause bulking. Several oligonucleotide 16S rRNA-targeted probes were designed to target filaments with a needle-like appearance similar to Haliscomenobacter hydrossis. The design of these probes was based on an isolate and a sequence obtained from a micromanipulated filament. The abundance of filamentous Bacteroidetes was determined in 126 industrial samples applying already published and the newly developed probes. Small populations were found in 62 % of the WWTP investigated. However, only relatively few WWTP (13 %) contained large populations of filamentous Bacteroidetes potentially responsible for bulking incidences. The identity of the most abundant filamentous Bacteroidetes with H. hydrossis morphology could be detected by probes CFB719, SAP-309 and the newly designed probe HHY-654. A comprehensive study on the ecophysiology of probe-defined Bacteroidetes populations was conducted on Danish and Czech samples. The studies revealed that they were specialized bacteria involved in degradation of sugars, e.g. glucose and N-acetylglucosamine, and may participate in the conversion of lipopolysaccharides and peptidoglycan liberated by decaying cells. Many surface-associated exo-enzymes were excreted, e.g. chitinase, glucuronidase, esterase and phosphatase, supporting conversion of polysaccharides and possibly other released cell components. The role of filamentous bacteria with a H. hydrossis-like morphology in the activated sludge ecosystem is discussed.
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark.
authors.forename: Caroline
authors.initials: C
authors.lastname: Kragelund
authors.affiliation: CNR, Water Research Institute, Via Reno 1, 00198 Rome, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Levantesi
authors.affiliation: Grontmij, De Holle Bilt 22, 3732 HM De Bilt Postbus 203, 3730 AE De Bilt, The Netherlands.
authors.forename: Arjan
authors.initials: A
authors.lastname: Borger
authors.affiliation: VERMICON AG, Emmy-Noether-Str. 2, 80992 Munich, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Thelen
authors.affiliation: ASIS vof, Deventerweg 38, 7203 AK Zutphen, The Netherlands.
authors.forename: Dick
authors.initials: D
authors.lastname: Eikelboom
authors.affiliation: CNR, Water Research Institute, Via Reno 1, 00198 Rome, Italy.
authors.forename: Valter
authors.initials: V
authors.lastname: Tandoi
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark.
authors.forename: Yunhong
authors.initials: Y
authors.lastname: Kong
authors.affiliation: BIOCLEAR Environmental Biotechnology, Rozenburglaan 13, 9727 DL Groningen, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Krooneman
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark.
authors.forename: Poul
authors.initials: P
authors.lastname: Larsen
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark.
authors.forename: Trine Rolighed
authors.initials: TR
authors.lastname: Thomsen
authors.affiliation: Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, DK-9000 Aalborg, Denmark.
authors.forename: Per Halkjær
authors.initials: PH
authors.lastname: Nielsen
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D041963:Bacteroidetes / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D044822:Biodiversity; D050260:Carbohydrate Metabolism; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D000431:Ethanol / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D007220:Industrial Waste; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D012722:Sewage / Q000382:microbiology*
chemical_list: D000596:Amino Acids; D017931:DNA Primers; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D007220:Industrial Waste; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D000431:Ethanol