Project description:Saccharibacteria (TM7) are obligate epibionts living on the surface of their host bacteria, and strongly correlated with dysbiotic microbiomes during periodontitis and other inflammatory diseases, suggesting they are putative pathogens. However, due to the recalcitrance of TM7 cultivation, no causal research has been conducted to investigate their role in inflammatory diseases. Here, we isolated multiple TM7 species on their host bacteria from periodontitis patients. These TM7 species reduced inflammation and consequential bone loss by modulating their host bacterial pathogenicity in mouse ligature-induced periodontitis model. Two host bacterial functions involved in collagen binding and utilization of eukaryotic sialic acid were identified as required for inducing bone loss and altered by TM7 association. This down-regulation of host bacterial pathogenicity by TM7 was shown for multiple TM7/host bacteria pairs, suggesting that, in contrast to their suspected pathogenic role, TM7 could protect mammalian hosts from inflammatory damage induced by their host bacteria.

2023-03-11 | PXD026999 | Pride

Transcriptome of epibiont Saccharibacteria TM7x during establishment of symbiosis on host Schaalia odontolyticus strain XH001

Project description:Nanosynbacter lyticus type strain TM7x was the first cultivated member of the broadly prevelent, but poorly udnerstood Candidate Phylum Radiation super-phylum. TM7x was shown to be an obligate epibiont with a host range including Schaalia odontolyticus strain XH001. The process of infecting a naive host goes through multiple phases, from an initial binding and interaction phase we call the initial encounter, to a rapid die off of infected host cells, killing phase, followed by regrowth of the host cells, regrowth phase, and finally a stable symbiosis between the species, stable symbiosis.To obtain a better understanding of the process by which these species establish a stable symbiosis, we measured the transcriptome using RNA sequencing across the course of infection. We sampled infected host, XH001/TM7x, during the initial interaction, regrowth, and after attaining stable symbiosis, as well as naive host controls grown under the same culture conditions.

2022-07-18 | GSE196744 | GEO

Candidatus Saccharibacteria bacterium YM_S32_TM7_50_20

Project description:Candidatus Saccharibacteria bacterium YM_S32_TM7_50_20 Genome sequencing

| PRJNA419966 | ENA

candidate division TM7 bacterium JGI 0001002-L20

Project description:candidate division TM7 bacterium JGI 0001002-L20

| PRJNA176055 | ENA