title: Occurrence and molecular characterization of cultivable mesophilic and thermophilic obligate anaerobic bacteria isolated from paper mills.
abstract: The aim of this work was to characterize the cultivable obligate anaerobic bacterial population in paper mill environments. A total of 177 anaerobically grown bacterial isolates were screened for aerotolerance, from which 67 obligate anaerobes were characterized by automated ribotyping and 41 were further identified by partial 16S rDNA sequencing. The mesophilic isolates indicated 11 different taxa (species) within the genus Clostridium and the thermophilic isolates four taxa within the genus Thermoanaerobacterium and one within Thermoanaerobacter (both formerly Clostridium). The most widespread mesophilic bacterium was closely related to C. magnum and occurred in three of four mills. One mill was contaminated with a novel mesophilic bacterium most closely related to C. thiosulfatireducens. The most common thermophile was T. thermosaccharolyticum, occurring in all four mills. The genetic relationships of the mill isolates to described species indicated that most of them are potential members of new species. On the basis of identical ribotypes clay could be identified to be the contamination source of thermophilic bacteria. Automated ribotyping can be a useful tool for the identification of clostridia as soon as comprehensive identification libraries are available.
authors.affiliation: VTT Biotechnology, P.O. Box 1500, FI-02044 VTT, Finland. maija-liisa.suihko@vtt.fi
authors.forename: Maija-Liisa
authors.initials: ML
authors.lastname: Suihko
authors.forename: Laila
authors.initials: L
authors.lastname: Partanen
authors.forename: Tiina
authors.initials: T
authors.lastname: Mattila-Sandholm
authors.forename: Laura
authors.initials: L
authors.lastname: Raaska
mesh_terms: D001421:Bacteria, Anaerobic / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D015373:Bacterial Typing Techniques; D003013:Clostridium / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis; D006358:Hot Temperature; D007218:Industrial Microbiology / Q000379:methods*; D010209:Paper; D021521:Ribotyping; D017422:Sequence Analysis, DNA; D046968:Thermoanaerobacter / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification; D046950:Thermoanaerobacterium / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial