%0 Journal Article %A Breznak, John A. %A Warnecke, Falk %T Spirochaeta cellobiosiphila sp. nov., a facultatively anaerobic, marine spirochaete %D 2008 %J International Journal of Systematic and Evolutionary Microbiology, %V 58 %N 12 %P 2762-2768 %@ 1466-5034 %R https://doi.org/10.1099/ijs.0.2008/001263-0 %I Microbiology Society, %X A facultatively anaerobic, marine spirochaete, designated strain SIP1T, was isolated from interstitial water from a cyanobacteria-containing microbial mat. Cells of strain SIP1T were 0.3–0.4×10–12 μm in size, helical with a body pitch of approximately 1.4 μm and motile by means of two to four periplasmic flagella (one, or occasionally two, being inserted near each end of the cell). Cells were catalase-negative and used a variety of monosaccharides and disaccharides and pectin as energy sources, growing especially well on cellobiose. Neither organic acids nor amino acids were utilized as energy sources. One or more amino acids in tryptone and one or more components of yeast extract were required for growth. Growth was observed at 9–37 °C (optimally at or near 37 °C), at initial pH 5–8 (optimally at initial pH 7.5) and in media prepared with 20–100 % (v/v) seawater (optimally at 60–80 %) or 0.10–1.00 M NaCl (optimally at 0.30–0.40 M). The products of cellobiose fermentation were acetate, ethanol, CO2, H2 and small amounts of formate. Aerated cultures performed incomplete oxidation of cellobiose to acetate (and, presumably, CO2) plus small amounts of ethanol and formate, but exhibited a Y cellobiose that was only slightly greater than that of cellobiose-fermenting anoxic cultures. The G+C content of the genomic DNA of strain SIP1T was 41.4 mol%, the lowest among known spirochaetas. On the basis of its 16S rRNA gene sequence, strain SIP1T was grouped among other members of the genus Spirochaeta, but it bore only 89 % similarity with respect to its closest known relatives, Spirochaeta litoralis and Spirochaeta isovalerica, two marine obligate anaerobes. On the basis of its phenotypic properties and phylogenetic position, strain SIP1T represents a novel species of the genus Spirochaeta, for which the name Spirochaeta cellobiosiphila sp. nov. is proposed. The type strain is SIP1T (=ATCC BAA-1285T =DSM 17781T). %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.2008/001263-0