A novel species of lactic acid bacteria, Ligilactobacillus pabuli sp. nov., isolated from alfalfa silage

Int J Syst Evol Microbiol. 2022 Oct;72(10). doi: 10.1099/ijsem.0.005587.


In this study, we isolated a novel strain of lactic acid bacteria, AF129T, from alfalfa silage prepared locally in Morioka, Iwate, Japan. Polyphasic taxonomy was used to characterize the bacterial strain. The bacterium was rod-shaped, Gram-stain-positive, non-spore-forming and catalase-negative. The strain grew at various temperatures (15-40°C) and pH levels (4.0-8.0). The optimum growth conditions were a temperature of 30°C and a pH of 6.0. AF129T exhibited growth at salt (NaCl) concentrations of up to 6.5 % (w/v). The G+C content of the strain's genomic DNA was 41.5 %. The major fatty acids were C16 : 0, C18 : 1ω9c, C19 : 0cyclo ω8c and summed feature 8. 16S rRNA gene sequencing revealed that AF129T represents a member of the genus Ligilactobacillus and it has higher sequence similarities with Ligilactobacillus pobuzihii (98.4 %), Ligilactobacillus acidipiscis (97.5 %) and Ligilactobacillus salitolerans (97.4 %). The digital DNA-DNA hybridization values for AF129T and phylogenetically related species of the genus Ligilactobacillus ranged from 19.8% to 24.1%. The average nucleotide identity of the strain with its closely related taxa was lower than the threshold (95 %-96 %) used for species differentiation. In the light of the above-mentioned physiological, genotypic, chemotaxonomic and phylogenetic evidence, we confirm that AF129T represents a member of the genus Ligilactobacillus and constitutes a novel species; we propose the name Ligilactobacillus pabuli sp. nov. for this species. The type strain is AF129T =MAFF 518002T =JCM 34518T=BCRC 81335T.

Keywords: Bacillota; Ligilactobacillus pabuli; alfalfa silage; lactic acid bacteria.

MeSH terms

  • Bacterial Typing Techniques
  • Base Composition
  • Catalase / genetics
  • DNA, Bacterial / genetics
  • Fatty Acids / chemistry
  • Lactobacillales* / genetics
  • Medicago sativa
  • Nucleotides
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA
  • Silage* / microbiology
  • Sodium Chloride


  • RNA, Ribosomal, 16S
  • Catalase
  • DNA, Bacterial
  • Sodium Chloride
  • Fatty Acids
  • Nucleotides