Tepidiphilus margaritifer gen. nov., sp. nov., isolated from a thermophilic aerobic digester

Abstract

Tepidiphilus margaritifer gen. nov., sp. nov., isolated from a thermophilic aerobic digester A moderately thermophilic bacterium is described, strain N2-214 T , that was isolated from an enrichment culture, growing on caprolactone, obtained from a sample from a water-treatment sludge aerobic digester operating at temperatures around 60 6C. The organism was aerobic, Gram-negative, oxidase-and catalase-positive, with a polar flagellum, and capable of growth at temperatures as high as 61 6C. The major fatty acids of strain N2-214 T were C 16 : 0 , C 18 : 1 and cyclo-C 19 : 0 . The phylogenetic relationships of the strain, derived from 16S rRNA gene sequence comparisons, demonstrated it to be a member of the b-subclass of the Proteobacteria. The highest 16S rDNA sequence similarity of isolate N2-214 T was to Azoarcus buckelii (91?9 %), Thauera aromatica (92 %) and Hydrogenophilus thermoluteolus (92?7 %). On the basis of phylogenetic analyses and physiological and chemotaxonomic characteristics, it is proposed that isolate N2-214 T (=DSM 15129 T =LMG 21637 T ) represents a new genus and species, Tepidiphilus margaritifer gen. nov., sp. nov.

Thiobacter subterraneus gen. nov., sp. nov., an obligately chemolithoautotrophic, thermophilic, sulfur-oxidizing bacterium from a subsurface hot aquifer

“…T was 66?9 mol%, a value similar to that of other thermophilic members of the bProteobacteria, including Hydrogenophilus thermoluteolus (63?5 mol%; Hayashi et al, 1999), Tepidiphilus margaritifer (64?8 mol%; Manaia et al, 2003), Thiobacillus aquaesulis (65?7 mol%; Wood & Kelly, 1988) and Tepidimonas ignava (69?7 %; Moreira et al, 2000) (Table 1).…”

“…The major cellular fatty acids of strain C55 T were C 16 : 0 (72?8 %), C 16 : 1 (23?1 %), C 18 : 0 (2?3 %), iso-C 18 : 0 (1?3 %) and C 18 : 1 (0?4 %). The ratio of n-C 16 fatty acids (95?9 % of the total fatty acids) in strain C55 T was high in comparison with other thermophilic micro-organisms within the b-Proteobacteria, such as Hydrogenophilus hirschii (58 %; Stöhr et al, 2001), Tepidimonas ignava (49 %; Moreira et al, 2000) or Tepidiphilus margaritifer (43 %; Manaia et al, 2003). Genomic DNA of strain C55 T was prepared as described by Marmur & Doty (1962).…”

“…In recent years, a number of workers using cultureindependent molecular analyses have reported the (Moreira et al, 2000); 4, Tepidiphilus margaritifer N2-214 T (Manaia et al, 2003); 5, Hydrogenophilus thermoluteolus TH-1 T (Hayashi et al, 1999); 6, Thiomonas thermosulfata ATCC 51520 T (Shooner et al, 1996). ND, Not described.…”

Spongiibacter tropicus sp. nov., isolated from a Synechococcus culture

“…The temperature range for growth was examined on the basis of colony formation on MA incubated at temperatures ranging from 5 to 45 u C (in increments of 5 u C). The pH range for growth was determined by assessing changes in OD 600 in pH-buffered MB (pH 5-11, in increments of 1 pH unit) (Manaia et al, 2003;Yumoto et al, 2004) at 30 u C for up to 7 days. The tolerance of strains CL-CB221 T and CL-CB467 to NaCl was determined by assessing changes in OD 600 in synthetic ZoBell broth (l 21 distilled water: 5 g Bacto peptone; 1 g yeast extract; 0.1 g ferric citrate) with 0-10 % (in increments of 1 %) and 15 % NaCl at 30 u C.…”

Cohaesibacter gelatinilyticus gen. nov., sp. nov., a marine bacterium that forms a distinct branch in the order Rhizobiales, and proposal of Cohaesibacteraceae fam. nov.

“…Growth was tested on trypticase soy agar (TSA; BBL), fivefold-diluted TSA, Czapek-Dox agar (Weyland, 1969), MacConkey agar (Difco) and blood agar (Difco) or the above media supplemented with either 3 % (w/v) NaCl or 3 % (w/v) sea salts (Sigma). The temperature range for growth was tested on the basis of colony formation on MA plates incubated at 5,10,15,20,25,30,31,33,35 and 40 u C. The pH range (pH 4-10 at intervals of 1 pH unit) for growth was determined both on the basis of colony formation on MA plates and assessing changes in OD 600 in pH-buffered marine broth medium (Difco) (Manaia et al, 2003). To test salt tolerance, R2A agar (Difco) containing various concentrations of NaCl [0, 0.5, 1, 2, 3, 5, 7, 10, 15, 20, 25 and 30 % (w/v)] were used.…”