Lactobacillus huangpiensis sp. nov. and Lactobacillus laiwuensis sp. nov., isolated from the gut of honeybee (Apis mellifera)
Ting Ting Li, Chun Tao Gu
Abstract
Four Gram-stain-positive bacterial strains were isolated from the gut of honeybee ( Apis mellifera ) in China. These strains were characterized using a polyphasic taxonomic approach. The data demonstrated that three of the four strains represented two novel species of the genus Lactobacillus , strains F306-1 T and F551-2 T were designated as the type strains. Results of 16S rRNA gene sequence analysis indicated that strains F306-1 T , F447 and F551-2 T were phylogenetically related to the type strains of Lactobacillus kimbladii and Lactobacillus kullabergensis , having 99.1–99.7 % 16S rRNA gene sequence (about 1400 bp) similarities. The phylogenetic tree based on concatenated pheS , rpoA , gyrB , hsp60 , recA , rpoB and tuf sequences (4114 bp) and the phylogenomic tree based on whole genome sequences indicated that strains F306-1 T and F447 were most closely related to L. kullabergensis Biut2N T , and strain F551-2 T was most closely related to L. kimbladii Hma2N T . Strains F306-1 T and F447 shared 99.9 % average nucleotide identity (ANI), 99.7 % digital DNA–DNA hybridization (dDDH) and 99.9 % average amino acid identity (AAI) values, indicating that they belong to the same species. Strain F306-1 T exhibited the highest ANI (94.4 %), dDDH (56.7 %) and AAI (94.7 %) values to L. kullabergensis Biut2N T . Strain F551-2 T had the highest ANI (94.0 %), dDDH (54.3 %) and AAI (95.8 %) values with L. kimbladii Hma2N T . Acid production from amygdalin, maltose, starch, gentiobiose and turanose, activity of esterase (C4) and α -glucosidase, growth with 3 % NaCl at 37 °C under strict anaerobic condition (on mMRS agar plates), and growth with 1–6% NaCl at 37 °C under aerobic condition (on mMRS agar plates supplemented with 0.05 % cysteine or with 1 % cysteine and 2 % fructose) could differentiate strains F306-1 T and F447 from L. kullabergensis DSM 26262 T . Acid production from d -glucose, arbutin and gentiobiose, growth with 3 % NaCl at 37 °C under strict anaerobic condition (on mMRS agar plates), and growth at 45 °C under strict anaerobic condition (on mMRS agar plates) could differentiate strain F551-2 T from L. kimbladii DSM 26263 T . Based upon the data obtained in the present study, two novel species, Lactobacillus huangpiensis sp. nov. and Lactobacillus laiwuensis sp. nov., are proposed and the type strains are F306-1 T (=LMG 32144 T =JCM 34361 T =CCTCC AB 2020300 T ) and F551-2 T (=JCM 34502 T =CCTCC AB 2021027 T ), respectively.