A Novel Archaeal Lineage in Boiling Hot Springs around Oyasukyo Gorge (Akita, Japan)

Microbes Environ. 2021;36(4):ME21048. doi: 10.1264/jsme2.ME21048.

Abstract

A novel deep-branching archaeal lineage was discovered at high-temperature hot springs around Oyasukyo Gorge in Akita Prefecture, Japan. Actively boiling hot spring water contained >1×104 microbes mL-1. The microbial community composition assessed by analyzing 16S rRNA gene amplicons revealed that the dominant bacterial phyla were Proteobacteria and Aquificae (>50% of the microbial composition) in samples collected in 2016 and 2019, respectively. Approximately 10% of the reads obtained in both years were not assigned to any taxonomy. The more detailed phylogenetic positions of the unassigned sequences identified using a clone library and phylogenetic tree showed that they formed a clade that was independent, distantly related to known phyla, and had low similarity (<82%) to all other sequences in available databases. The present results suggest that this novel archaeal phylum-level lineage thrives in boiling hot springs in Japan.

Keywords: boiling hot spring; hyperthermophile; novel archaeal lineage; thermophile.

MeSH terms

  • Archaea / classification*
  • Bacteria / classification
  • Biodiversity
  • DNA, Archaeal / genetics
  • Hot Springs / microbiology*
  • Japan
  • Phylogeny*
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA

Substances

  • DNA, Archaeal
  • RNA, Ribosomal, 16S