Microbiology Resource Announcements

Here, we report draft genome sequences for nine strains of “ Candidatus Nanosynbacter sp. HMT-352.” These strains and their sequences were used to interrogate strain-level variations in host range, gene content, and growth dynamics among the phylum “ Candidatus Saccharibacteria.”

Saccharibacteria are abundant and diverse members of the human oral microbiome; however, they are poorly understood and appear to exhibit an epibiont/parasitic lifestyle dependent on host bacteria. Here, a complete metagenome-assembled genome (MAG) sequence of an organism from Saccharibacteria clade G1 human microbial taxon (HMT) 348 is reported, strain HMT-348_TM7c-JB.

The bacterium “ Candidatus Hydrogenosomobacter endosymbioticus” is an intracellular symbiont of anaerobic scuticociliate GW7, which is associated with hydrogenosome together with methanogenic archaea. Here, we report a complete genome sequence of the symbiont consisting of 827 kbp. Knowing this sequence would contribute to the understanding of the metabolic interactions and evolution of the tripartite symbiosis.

“Cand. Nanosynbacter sp. HMT352” strain KC1 is an ectoparasitic saccharibacterium/TM7 that was co-isolated from a human saliva sample with its obligate bacterial host, Schaalia odontolytica . The genome of strain KC1 enables studies of the mechanisms and evolution of interspecies interactions and, for oral species, studies of their potential roles in health and disease.

Little is known about the bacterial phylum “ Candidatus Dependentiae,” because only three isolates have been reported. Here, I report the isolation and genome sequencing of a new member of this phylum, strain Noda2021. This is the fourth strain isolated from the phylum “ Candidatus Dependentiae.”

The full genome of a Methanomassiliicoccales strain, U3.2.1, was obtained from enrichment cultures of percolation fen peat soil under methanogenic conditions, with methanol and hydrogen as the electron acceptor and donor, respectively. Metagenomic assembly of combined long-read and short-read sequences resulted in a 1.51-Mbp circular genome.

Here, we report the draft, nearly complete genome sequence of the human oral actinobacterium Schaalia odontolytica strain ORNL0103, which was isolated in association with “ Candidatus Saccharibacteria” HMT352 strain ORNL0105. The genome was sequenced using a combination of Pacific Biosciences and Illumina platforms and encodes 1,948 proteins and 60 RNAs.

A plethora of hot springs are found at the Los Azufres volcanic complex in Mexico, and studies are needed to determine their microbial genomic diversity. Here, we report a metagenome of hot spring sediments and a metagenome-assembled genome of “ Candidatus Aramenus sulfurataquae.” This study reveals novel genomic sequences of Sulfolobales archaea.

We report the complete genome sequence and annotation of “ Candidatus Nardonella dryophthoridicola” strain NardRF, obtained by sequencing its host bacteriome, Rhynchophorus ferrugineus , using Oxford Nanopore technology.

At least 6 highly diverse clades of Saccharibacteria inhabit the human oral cavity. However, all oral Saccharibacteria strains with currently available complete genome sequences or cultured isolates belong to clade G1, leaving clades G2 through G6 poorly understood. Here, a complete genome sequence of JB001, a clade G6 (“ Candidatus Nanogingivalaceae”) Saccharibacteria strain, is reported.