Agrilactobacillus fermenti sp. nov. isolated from fermented vegetable residue

Abstract

A polyphasic taxonomic approach was used to characterize a Gram-stain-positive fermentative bacterium, designated strain CC-MHH1034T, isolated from a fermented vegetable residue. Cells of strain CC-MHH1034T were facultatively anaerobic, non-motile, and non-spore-forming rods, exhibiting positive catalase, oxidase and protease activities. Optimal growth occurred at 30 °С and pH 6.0. Strain CC-MHH1034T shared the highest 16S rRNA gene sequence similarities with Agrilactobacillus composti (95.9 %) followed by Agrilactobacillus yilanensis (95.1 %) and established a distinct taxonomic lineage associated with these species. Highest orthologous average nucleotide identity (OrthoANI) values were recorded for strain CC-MHH1034T versus Agrilactobacillus (71.1–71.6 %, n=2) followed by Ligilactobacillus (66.5–66.8 %, n=2), Lactobacillus (64.1–65.8 %, n=4). The mean digital DNA–DNA hybridization (dDDH) value obtained for strain CC-MHH1034T against Agrilactobacillus was 19.2–19.5 % (n=2). The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, two unidentified aminolipids, four unidentified glycolipids, four unidentified phospholipids and one unidentified lipid. The major polyamine was sym-homospermidine and meso-diaminopimelic acid was detected as the cell-wall peptidoglycan. The dominating cellular fatty acids (>5 %) included C16 : 0, iso-C15 : 0, anteiso-C15 : 0 and C18 : 1  ω9c. Based on its distinct phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence, OrthoANI, dDDH, and the phylogenomic placement, strain CC-MHH1034T is considered to represent a novel species of the genus Agrilactobacillus , affiliated to the family Lactobacillaceae , for which the name Agrilactobacillus fermenti sp. nov. is proposed. The type strain is CC-MHH1034T (=BCRC 81220T=JCM 33476T).