Enorma shizhengliae sp. nov. and Eggerthella guodeyinii sp. nov., two new members of the family Coriobacteriaceae

Abstract

Four obligatory anaerobic, Gram-stain-positive, non-motile and rod-shaped organisms (HF-1365^T, HF-1362, HF-1101^T and HF-4214) were isolated from faecal samples of healthy Chinese subjects. Results of 16S rRNA gene sequence analyses showed that these isolates belong to the genera Enorma (strains HF-1365^T and HF-1362) and Eggerthella (strains HF-1101^T and HF-4214), closest to Enorma massiliensis (both 98.6 %) and Eggerthella sinensis (98.0 and 97.8 %), respectively. The whole genome sequences of strains HF-1365^T and HF-1101^T were 2.3 and 4.2 Mb in size with 61.7 and 66.2 mol% DNA G+C content, respectively. The average nucleotide identity and digital DNA-DNA hybridization values indicated that strains HF-1365^T and HF-1101^T represent novel species in the genera Enorma and Eggerthella. Major fatty acid constituents (>10 %) of strains HF-1365^T and HF-1362 were C_{12 : 0} (24.7 and 23.9 %), C_{14 : 0} (21.9 and 20.6 %) and summed feature 1 (C_{15 : 1}iso H/C_{13 : 0} 3OH; 12.8 and 10.8 %); those of strains HF-1101^T and HF-4214 were C_{18 : 1} ω9c (32.4 and 33.1 %) and C_{16 : 0} (13.9 and 14.0 %). Strain HF-1365^T had phospholipid, glycolipid, lipid and phosphoglycolipid without any known quinones, while strain HF-1101^T had diphosphatidylglycerol as the major polar lipid and MK-7 (80.7 %) as the predominant quinone. On the basis of their phylogenetic and phenotypic characteristics, strains HF-1365^T and HF-1101^T represent two distinct species, respectively, in the genera Enorma and Eggerthella, for which the names Enorma shizhengliae sp. nov. (type strain HF-1365^T=CGMCC 1.17435^T=GDMCC 1.1705^T=JCM 33601^T) and Eggerthella guodeyinii sp. nov. (type strain HF-1101^T=CGMCC 1.17436^T=GDMCC 1.1668^T=JCM 33773^T) are proposed.

Keywords: Eggerthella guodeyinii sp. nov.; Enorma shizhengliae sp. nov.; gut microbiota; taxonomy.