Oscillibacter ruminantium sp. nov., isolated from the rumen of Korean native cattle

Abstract

A strictly anaerobic, Gram-negative, non-spore-forming bacterium, designated GH1^T, was isolated from the rumen of Korean native cattle (HanWoo). Cells were straight to slightly curved rods (2.0–4.5 µm long) and were motile by peritrichous flagella. The isolate grew at 30–45 °C (optimum 40 °C), at pH 5.5–6.5 (optimum pH 6.0) and with up to 3.5 % (w/v) NaCl. Strain GH1^Tproduced acid fromd-glucose,d-ribose andd-xylose, with butyric acid being the major end product. The genomic DNA G+C content was 54.6 mol%. Based on comparative 16S rRNA gene sequence analysis, strain GH1^Twas most closely related to Oscillibacter valericigenes Sjm18-20^T(97.3 % 16S rRNA gene sequence similarity). DNA–DNA hybridization between strain GH1^Tand O. valericigenes DSM 18026^Tshowed 24 % reassociation. The major fatty acids were iso-C_13 : 0(13.0 %), iso-C_15 : 0(17.6 %), anteiso-C_15 : 0(8.4 %) and C_14 : 0(4.1 %), and the cellular fatty acid methyl esters as dimethylacetals (DMAs) were C_16 : 0DMA (17.8 %), iso-C_15 : 0DMA (15.2 %) and C_14 : 0DMA (4.52 %). The cell-wall peptidoglycan of strain GH1^Tcontainedmeso-diaminopimelic acid and the major cell-wall sugar was galactose. Based on 16S rRNA gene sequence similarity, phylogenetic analysis, DNA G+C content, DNA–DNA relatedness and distinct phenotypic characteristics, strain GH1^Tis classified in the genus Oscillibacter as a member of a novel species, for which the name Oscillibacter ruminantiumsp. nov. is proposed. The type strain is GH1^T( = KCTC 15176^T = NBRC 108824^T = JCM 18333^T).