title: Ecophysiology of different filamentous Alphaproteobacteria in industrial wastewater treatment plants.
abstract: The ecophysiology of five filamentous species affiliated to the Alphaproteobacteria was investigated in industrial activated sludge systems. The five species, 'Candidatus Alysiosphaera europaea', 'Candidatus Monilibacter batavus', 'Candidatus Alysiomicrobium bavaricum', 'Candidatus Sphaeronema italicum' and Meganema perideroedes, are very abundant in industrial wastewater treatment plants and are often involved in bulking incidents. The morphology of these filamentous bacterial species resembled Eikelboom's Nostocoida limicola, or Type 021N, and could only be correctly identified by using fluorescence in situ hybridization (FISH), applying species-specific gene probes. Two physiological groupings of the five species were found using microautoradiography combined with FISH. Group 1 ('Ca. Monilibacter batavus' and 'Ca. Sphaeronema italicum') utilized many short-chained fatty acids (acetate, pyruvate and propionate), whereas Group 2 ('Ca. Alysiosphaera europaea', 'Ca. Alysiomicrobium bavaricum' and Meganema perideroedes) could also exploit several sugars, amino acids and ethanol. All species had polyhydroxyalkanoate granules present and several of the species had a very large storage capacity. No activity was found under strict anaerobic conditions, while uptake of substrate was observed in the presence of nitrate or nitrite as potential electron acceptor. However, for all species a reduced number of substrates could be consumed under these conditions compared to aerobic conditions. Only a little exo-enzymic activity was found and nearly all species had a hydrophobic cell surface. Based on knowledge of the ecophysiological potential, control strategies are suggested.
authors.affiliation: Section of Environmental Engineering, 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: Section of Environmental Engineering, 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 BV, Rozenburglaan 13, 9727 DL Groningen, The Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: van der Waarde
authors.affiliation: VERMICON AG, Emmy-Noether-Str. 2, 80992 München, 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: Section of Environmental Engineering, 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: Section of Environmental Engineering, 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: D000332:Aerobiosis; D020561:Alphaproteobacteria / Q000145:classification / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D000596:Amino Acids / Q000378:metabolism; D000693:Anaerobiosis; D001426:Bacterial Proteins / Q000032:analysis; D015373:Bacterial Typing Techniques; D050260:Carbohydrate Metabolism; D003594:Cytoplasmic Granules / Q000737:chemistry; D017753:Ecosystem; D004798:Enzymes / Q000032:analysis; D000431:Ethanol / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D017404:In Situ Hybridization, Fluorescence; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D011108:Polymers / Q000032:analysis; D012722:Sewage / Q000382:microbiology*; D014871:Water Microbiology; D018508:Water Purification
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D004798:Enzymes; D005227:Fatty Acids; D009566:Nitrates; D009573:Nitrites; D011108:Polymers; D012722:Sewage; D000431:Ethanol