%0 Journal Article %A Kulichevskaya, Irina S. %A Danilova, Olga V. %A Tereshina, Vera M. %A Kevbrin, Vadim V. %A Dedysh, Svetlana N. %T Descriptions of Roseiarcus fermentans gen. nov., sp. nov., a bacteriochlorophyll a-containing fermentative bacterium related phylogenetically to alphaproteobacterial methanotrophs, and of the family Roseiarcaceae fam. nov. %D 2014 %J International Journal of Systematic and Evolutionary Microbiology, %V 64 %N Pt_8 %P 2558-2565 %@ 1466-5034 %R https://doi.org/10.1099/ijs.0.064576-0 %I Microbiology Society, %X A light-pink-pigmented, microaerophilic bacterium was obtained from a methanotrophic consortium enriched from acidic Sphagnum peat and designated strain Pf56T. Cells of this bacterium were Gram-negative, non-motile, thick curved rods that contained a vesicular intracytoplasmic membrane system characteristic of some purple non-sulfur alphaproteobacteria. The absorption spectrum of acetone/methanol extracts of cells grown in the light showed maxima at 363, 475, 505, 601 and 770 nm; the peaks at 363 and 770 nm are characteristic of bacteriochlorophyll a. However, in contrast to purple non-sulfur bacteria, strain Pf56T was unable to grow phototrophically under anoxic conditions in the light. Best growth occurred on some sugars and organic acids under micro-oxic conditions by means of fermentation. The fermentation products were propionate, acetate and hydrogen. Slow chemo-organotrophic growth was also observed under fully oxic conditions. Light stimulated growth. C1 substrates were not utilized. Strain Pf56T grew at pH 4.0–7.0 (optimum pH 5.5–6.5) and at 15–30 °C (optimum 22–28 °C). The major cellular fatty acids were 19 : 0 cyclo ω8c and 18 : 1ω7c; quinones were represented by ubiquinone Q-10. The G+C content of the DNA was 70.0 mol%. Strain Pf56 displays 93.6–94.7 and 92.7–93.7 % 16S rRNA gene sequence similarity to members of the families Methylocystaceae and Beijerinckiaceae , respectively, and belongs to a large cluster of environmental sequences retrieved from various wetlands and forest soils in cultivation-independent studies. Phenotypic, genotypic and chemotaxonomic characteristics of strain Pf56T suggest that it represents a novel genus and species of bacteriochlorophyll a-containing fermentative bacteria, for which the name Roseiarcus fermentans gen. nov., sp. nov. is proposed. Strain Pf56T ( = DSM 24875T = VKM B-2876T) is the type strain of Roseiarcus fermentans, and is also the first characterized member of a novel family within the class Alphaproteobacteria , Roseiarcaceae fam. nov. %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.064576-0