Clostridium uliginosum sp. nov., a novel acid-tolerant, anaerobic bacterium with connecting filaments

Int J Syst Evol Microbiol. 2001 May;51(Pt 3):1119-1125. doi: 10.1099/00207713-51-3-1119.


An anaerobic, acid-tolerant bacterium, CK55T, was isolated from an acidic forest bog. Cells of CK55T stained Gram-negative but did not have an outer membrane. Cells were spore-forming, motile rods with peritrichous flagella, formed chains or aggregates and were linked by connecting filaments that were composed of a core and outer sheath. Cellobiose, glucose, xylose, mannose, mannitol, sucrose and peptone supported growth. Arabinose, lactose, raffinose, H2/CO2, CO/CO2, vanillate, Casamino acids and various purines and pyrimidines did not support growth. Growth on carbohydrates yielded acetate, butyrate, lactate, formate and H2 as end-products. Growth was observed at pH 4.0-9.0, with an optimum at pH 6.5, and at 10-30 degrees C, with an optimum at 20-25 degrees C. At 20 degrees C, doubling times were 4 and 6 h at pH 6.5 and 4.0, respectively. Hydrogenase activity in cell-free extracts was 12 U (mg protein)-1. CK55T did not: (i) contain detectable levels of CO, formate, lactate dehydrogenases or cytochromes; (ii) carry out dissimilatory reduction of nitrate or sulfate; or (iii) produce methane. Thus, CK55T was characterized as a non-acetogenic, fermentative chemo-organotroph. The G+C content of CK55T was 28.0 mol%. CK55T was phylogenetically most closely related to Clostridium botulinum (types B, E and F), Clostridium acetobutylicum and other saccharolytic clostridia; the 16S rRNA gene sequence similarity values to the nearest relatives of CK55T were approximately 97%. Based on morphological, physiological and phylogenetic properties of CK55T, it is proposed that CK55T be termed Clostridium uliginosum sp. nov. (= DSM 12992T = ATCC BAA-53T).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Base Sequence
  • Carbohydrate Metabolism
  • Clostridium / classification*
  • Clostridium / genetics
  • Clostridium / physiology
  • Clostridium / ultrastructure
  • DNA, Ribosomal / genetics
  • Enzymes / analysis
  • Microscopy, Electron
  • Molecular Sequence Data
  • Phylogeny*
  • RNA, Ribosomal, 16S / genetics
  • Soil Microbiology


  • DNA, Ribosomal
  • Enzymes
  • RNA, Ribosomal, 16S

Associated data

  • GENBANK/AJ276992