title: Novel lineages of Planctomycetes densely colonize the alkaline gut of soil-feeding termites (Cubitermes spp.).
abstract: Members of the phylum Planctomycetes are found in aquatic and terrestrial habitats. Here we show that the highest density of Planctomycetes in natural environments (2.6 x 10(9) cells ml(-1)) is encountered in the hindgut of soil-feeding termites (Cubitermes spp.), where they constitute up to one-third of the bacteria in the alkaline P3 compartment detected by fluorescent in situ hybridization (FISH). A 16S-rRNA-based approach revealed that the planctomycete community is very diverse and falls into three major clusters representing novel, deeply branching lineages. Terminal restriction fragment length polymorphism (T-RFLP) analysis and FISH with cluster-specific oligonucleotide probes confirmed that most of the lineages are also present in other gut compartments, albeit in much lower numbers, but absent from the food soil. The majority of planctomycetes in the gut belong to a large clade, the 'Termite planctomycete cluster', which consists exclusively of clones from termite guts and seems to be represented in all termite species.
authors.affiliation: Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse, 35043 Marburg, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Köhler
authors.forename: Ulrich
authors.initials: U
authors.lastname: Stingl
authors.forename: Katja
authors.initials: K
authors.lastname: Meuser
authors.forename: Andreas
authors.initials: A
authors.lastname: Brune
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D003001:Cloning, Molecular; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis; D004064:Digestive System / Q000382:microbiology*; D017753:Ecosystem; D006863:Hydrogen-Ion Concentration; D017404:In Situ Hybridization, Fluorescence; D020049:Isoptera / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S