Sporolactobacillus mangiferae sp. nov., a spore-forming lactic acid bacterium isolated from tree bark in Thailand

Int J Syst Evol Microbiol. 2023 Jul;73(7). doi: 10.1099/ijsem.0.005993.

Abstract

A Gram-stain-positive, facultatively anaerobic and endospore-forming rod-shaped bacterium, designed strain CPB3-1T, was isolated from tree bark. This homofermentative strain produced dl-lactic acid from glucose. It grew at 20-45 °C, pH 4.0-9.5 and in 0-3.0 % (w/v) NaCl. It contained meso-diaminopimelic acid in cell-wall peptidoglycan and had menaquinone with seven isoprene units (MK-7) as the predominant component. The major fatty acid was anteiso-C17 : 0. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol, an unknown phospholipid and an unknown lipid. Based on the results of 16S rRNA gene sequence analysis, strain CPB3-1T belonged to the genus Sporolactobacillus and was closely related to Sporolactobacillus kofuensis DSM 11701T and Sporolactobacillus spathodeae BK117-1T (both 96.7 % similarity), Sporolactobacillus inulinus NRIC 1133T and Sporolactobacillus terrae DSM 11697T (both 96.6 % similarity), and Sporolactobacillus shoreicorticis MK21-7T, Sporolactobacillus laevolacticus DSM 442T, Sporolactobacillus shoreae BK92T and Sporolactobacillus pectinivorans GD201205T (all 95.8-96.5 % similarity). The draft genome of strain CPB3-1T contained 2 930 919 bps with 3117 coding genes. The DNA G+C content was 45.1 mol%. The digital DNA-DNA hybridization values between strain CPB3-1T and closely related type strains were 19.2-24.0 %. The average nucleotide identity (84.0-87.6 %) and average amino acid identity (66.5-76.3 %) values were lower than the cut-off values for species delineation. Strain CPB3-1T was clearly distinguished from related Sporolactobacillus species based on its phenotypic and chemotaxonomic characteristics, 16S rRNA gene sequence similarity and the results of draft genome analysis. Therefore, the strain represents a novel species of the genus Sporolactobacillus, for which the name Sporolactobacillus mangiferae sp. nov. is proposed. The type strain is CPB3-1T (=JCM 35082T=TISTR 10004T).

Keywords: Sporolactobacillus mangiferae; lactic acid bacteria; polyphasic taxonomy; spore-forming bacteria; tree bark.

MeSH terms

  • Bacterial Typing Techniques
  • Base Composition
  • DNA, Bacterial / genetics
  • Fatty Acids* / chemistry
  • Lactic Acid
  • Phospholipids / chemistry
  • Phylogeny
  • Plant Bark* / microbiology
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA
  • Spores, Bacterial
  • Thailand

Substances

  • Fatty Acids
  • Lactic Acid
  • RNA, Ribosomal, 16S
  • DNA, Bacterial
  • Phospholipids