Preliminary landscape of Candidatus Saccharibacteria in the human microbiome

Valles, Camille; Abdillah, Abdourahim; Chacra, Linda Abou; Mekhalif, F.; Ibrahim, Ahmad; Caputo, Aurélia; Baudoin, Jean-Pierre; Gouriet, Frédérique; Bittar, Fadi; Lagier, Jean-Christophe; Ranque, Stéphane; Fénollar, Florence; Alou, Maryam Tidjani; Raoult, Didier

doi:10.3389/fcimb.2023.1195679

Cited by 3 publications

(1 citation statement)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…7 ). To our knowledge, the first two lineages have not been previously detected in mammalian microbiomes (Dojkabacteria was recently reported in humans [ 81 ]) and have no cultured representatives from any environment. When and how they became a part of the mammalian microbiota remains an open question.…”

Section: Resultsmentioning

confidence: 99%

From wolves to humans: oral microbiome resistance to transfer across mammalian hosts

Podar,

Carrell,

Cassidy

et al. 2024

mBio

View full text Add to dashboard Cite

The mammalian mouth is colonized by complex microbial communities, adapted to specific niches, and in homeostasis with the host. Individual microbes interact metabolically and rely primarily on nutrients provided by the host, with which they have potentially co-evolved along the mammalian lineages. The oral environment is similar across mammals, but the diversity, specificity, and evolution of community structure in related or interacting mammals are little understood. Here, we compared the oral microbiomes of dogs with those of wild wolves and humans. In dogs, we found an increased microbial diversity relative to wolves, possibly related to the transition to omnivorous nutrition following domestication. This includes a larger diversity of Patescibacteria than previously reported in any other oral microbiota. The oral microbes are most distinct at bacterial species or strain levels, with few if any shared between humans and canids, while the close evolutionary relationship between wolves and dogs is reflected by numerous shared taxa. More taxa are shared at higher taxonomic levels including with humans, supporting their more ancestral common mammalian colonization followed by diversification. Phylogenies of selected oral bacterial lineages do not support stable human-dog microbial transfers but suggest diversification along mammalian lineages (apes and canids). Therefore, despite millennia of cohabitation and close interaction, the host and its native community controls and limits the assimilation of new microbes, even if closely related. Higher resolution metagenomic and microbial physiological studies, covering a larger mammalian diversity, should help understand how oral communities assemble, adapt, and interact with their hosts. IMPORTANCE Numerous types of microbes colonize the mouth after birth and play important roles in maintaining oral health. When the microbiota-host homeostasis is perturbed, proliferation of some bacteria leads to diseases such as caries and periodontitis. Unlike the gut microbiome, the diversity of oral microbes across the mammalian evolutionary space is not understood. Our study compared the oral microbiomes of wild wolves, dogs, and apes (humans, chimpanzees, and bonobos), with the aim of identifying if microbes have been potentially exchanged between humans and dogs as a result of domestication and cohabitation. We found little if any evidence for such exchanges. The significance of our research is in finding that the oral microbiota and/or the host limit the acquisition of exogenous microbes, which is important in the context of natural exclusion of potential novel pathogens. We provide a framework for expanded higher-resolution studies across domestic and wild animals to understand resistance/resilience.

show abstract

Section: Resultsmentioning

confidence: 99%

From wolves to humans: oral microbiome resistance to transfer across mammalian hosts

Podar,

Carrell,

Cassidy

et al. 2024

mBio

View full text Add to dashboard Cite

show abstract

Saccharibacteria deploy two distinct Type IV pili, driving episymbiosis, host competition, and twitching motility

Grossman,

Lei,

Botting

et al. 2024

Preprint

View full text Add to dashboard Cite

All cultivated Patescibacteria, or CPR, exist as obligate episymbionts on other microbes. Despite being ubiquitous in mammals and environmentally, molecular mechanisms of host identification and binding amongst ultrasmall bacterial episymbionts are largely unknown. Type 4 pili (T4P) are well conserved in this group and predicted to facilitate symbiotic interactions. To test this, we targeted T4P pilin genes in Saccharibacteria Nanosynbacter lyticus strain TM7x to assess their essentiality and roles in symbiosis. Our results revealed that N. lyticus assembles two distinct T4P, a non-essential thin pili that has the smallest diameter of any T4P and contributes to host-binding, episymbiont growth, and competitive fitness relative to other Saccharibacteria, and an essential thick pili whose functions include twitching motility. Identification of lectin-like minor pilins and modification of host cell walls suggest glycan binding mechanisms. Collectively our findings demonstrate that Saccharibacteria encode unique extracellular pili that are vital mediators of their underexplored episymbiotic lifestyle.

show abstract

Periodontitis: etiology, conventional treatments, and emerging bacteriophage and predatory bacteria therapies

Łasica,

Golec,

Laskus

et al. 2024

Front. Microbiol.

View full text Add to dashboard Cite

Inflammatory periodontal diseases associated with the accumulation of dental biofilm, such as gingivitis and periodontitis, are very common and pose clinical problems for clinicians and patients. Gingivitis is a mild form of gum disease and when treated quickly and properly is completely reversible. Periodontitis is an advanced and irreversible disease of the periodontium with periods of exacerbations, progressions and remission. Periodontitis is a chronic inflammatory condition that damages the tissues supporting the tooth in its socket, i.e., the gums, periodontal ligaments, root cementum and bone. Periodontal inflammation is most commonly triggered by bacteria present in excessive accumulations of dental plaque (biofilm) on tooth surfaces. This disease is driven by disproportionate host inflammatory immune responses induced by imbalance in the composition of oral bacteria and changes in their metabolic activities. This microbial dysbiosis favors the establishment of inflammatory conditions and ultimately results in the destruction of tooth-supporting tissues. Apart microbial shift and host inflammatory response, environmental factors and genetics are also important in etiology In addition to oral tissues destruction, periodontal diseases can also result in significant systemic complications. Conventional methods of periodontal disease treatment (improving oral hygiene, dental biofilm control, mechanical plaque removal, using local or systemic antimicrobial agents) are not fully effective. All this prompts the search for new methods of therapy. Advanced periodontitis with multiple abscesses is often treated with antibiotics, such as amoxicillin, tetracycline, doxycycline, minocycline, clindamycin, or combined therapy of amoxicillin with metronidazole. However, due to the growing problem of antibiotic resistance, treatment does not always achieve the desired therapeutic effect. This review summarizes pathogenesis, current approaches in treatment, limitations of therapy and the current state of research on the possibility of application of bacteriophages and predatory bacteria to combat bacteria responsible for periodontitis. We present the current landscape of potential applications for alternative therapies for periodontitis based on phages and bacteria, and highlight the gaps in existing knowledge that need to be addressed before clinical trials utilizing these therapeutic strategies can be seriously considered.

show abstract

Preliminary landscape of Candidatus Saccharibacteria in the human microbiome

Cited by 3 publications

References 46 publications

From wolves to humans: oral microbiome resistance to transfer across mammalian hosts

From wolves to humans: oral microbiome resistance to transfer across mammalian hosts

Saccharibacteria deploy two distinct Type IV pili, driving episymbiosis, host competition, and twitching motility

Periodontitis: etiology, conventional treatments, and emerging bacteriophage and predatory bacteria therapies

Contact Info

Product

Resources

About