Mucispirillum schaedleri gen. nov., sp. nov., a spiral-shaped bacterium colonizing the mucus layer of the gastrointestinal tract of laboratory rodents

1 Ramaciotti Centre for Gene Function Analysis, The University of New South Wales, Sydney, NSW 2052, Australia 2 School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW 2052, Australia 3 Laboratorium voor Microbiologie, Universiteit Gent, Ledeganckstraat 35, B-9000 Gent, Belgium 4 Danish Veterinary Laboratory, Bülowsvej 27, DK-1790 Copenhagen V, Denmark 5 Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA Correspondence Jani L. O'Rourke J.orourke{at}unsw.edu.au The mammalian gastrointestinal tract is covered by a layer of mucus that can harbour a range of bacterial species specifically adapted to colonize this ecological niche. Examination of 110 bacterial isolates cultivated from the gastrointestinal tract of 23 mice revealed the presence of a subgroup of 30 isolates that did not correspond genetically with genera commonly associated with this site, i.e. members of the - Proteobacteria such as Helicobacter and Campylobacter species. Instead this group of isolates was found to lie within the phylum Deferribacteres , a completely distinct lineage in the domain Bacteria . There was a high level of consensus in results obtained from the phenotypic and genotypic characterization of a number of the isolates, which showed they were distinct from other members of the Deferribacteres . As such, they are proposed to constitute a new genus and species, Mucispirillum schaedleri gen. nov., sp. nov. These organisms are anaerobic, Gram-negative, spiral-shaped rods with bipolar flagella. The type strain is HRI I17 T (=ATCC BAA-1009 T =ACM 5223 T ). Abbreviations: GT, gastrointestinal tract Published online ahead of print on 4 January 2005 as DOI 10.1099/ijs.0.63472-0. The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene sequences of nine Mucispirillum schaedleri isolates are AF059186 –AF059190 and AY387668 –AY387671. A dendrogram based on whole-cell protein profiles of ten Mucispirillum schaedleri isolates is available as supplementary material in IJSEM Online.