Analysis of oral microbiome from fossil human remains revealed the significant differences in virulence factors of modern and ancient Tannerella forsythia

AbstractThe human microbiome has been the focus of numerous research efforts to elucidate the pathogenesis of human diseases including cancer. Oral cancer mortality is high when compared with other cancers, as diagnosis often occurs during late stages. Its prevalence has increased in the USA over the past decade and accounts for over 40,000 new cancer patients each year. Additionally, oral cancer pathogenesis is not fully understood and is likely multifactorial. To unravel the relationships that are associated with the oral microbiome and their virulence factors, we used 16S rDNA and metagenomic sequencing to characterize the microbial composition and functional content in oral squamous cell carcinoma (OSCC) tumor tissue, non-tumor tissue, and saliva from 18 OSCC patients. Results indicate a higher number of bacteria belonging to the Fusobacteria, Bacteroidetes, and Firmicutes phyla associated with tumor tissue when compared with all other sample types. Additionally, saliva metaproteomics revealed a significant increase of Prevotella in five OSCC subjects, while Corynebacterium was mostly associated with ten healthy subjects. Lastly, we determined that there are adhesion and virulence factors associated with Streptococcus gordonii as well as from known oral pathogens belonging to the Fusobacterium genera found mostly in OSCC tissues. From these results, we propose that not only will the methods utilized in this study drastically improve OSCC diagnostics, but the organisms and specific virulence factors from the phyla detected in tumor tissue may be excellent biomarkers for characterizing disease progression.

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An in silico Analysis of Protein Targeted by Glycyrrhizin in Common Dental Pathogens

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2020/v32i1530640 ◽

2020 ◽

pp. 170-178

Author(s):

S. Balamithra ◽

Smiline Girija ◽

J. Vijayashree Priyadharsini

Keyword(s):

Virulence Factors ◽

In Silico ◽

In Silico Analysis ◽

Subcellular Location ◽

Functional Class ◽

Treponema Denticola ◽

Peptic Ulcers ◽

Upper Respiratory Tract ◽

Tannerella Forsythia ◽

Medicinal Uses

Glycyrrhizin is a phytocompound which is derived from Glycyrrhiza glabra. It is used in treating the upper respiratory tract disease like cough, bronchitis, laryngitis, sore throat, etc. It has various medicinal uses in rheumatism, peptic ulcers, asthma, allergies, and inflammation. Glycyrrhizin has been reported to possess antibacterial, antiviral, antioxidant, anti inflammatory properties. In view of the above facts, the present in silico study was designed to demonstrate the molecular mechanism underlying the antimicrobial activity of glycyrrhizin against common dental pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Treponema denticola, Enterococcus faecalis and Tannerella forsythia. The STITCH tool was used to identify the drug-protein interaction. The functional class of the protein was deduced using VICMPred, followed by the identification of epitopes on the virulence factors using BepiPred. Further, the subcellular location of the virulence factors were also studied using PSORTb software. The computational analysis performed identified several virulence factors viz., short chain dehydrogenase/reductase family oxidoreductase of Treponema denticola and D-mannonate oxidoreductase of Tannerella forsythia which were found to interact with glycyrrhizin. Interestingly, phosphopyruvate hydratase was found to be the protein present in all the five genera was shown to interact with glycyrrhizin. Thus the present study reveals the target proteins on the dental pathogens which were shown to interact with glycyrrhizin. Furthermore, experimental validation of the results are warranted to provide substantial details on the anti-microbial activity of glycyrrhizin against common dental pathogens.

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Oral Dysbiotic Communities and Their Implications in Systemic Diseases

10.20944/preprints201803.0170.v1 ◽

2018 ◽

Author(s):

Preethi Sudhakara ◽

Abishek Gupta ◽

Anshumouli Bhardwaj ◽

Aruni Wilson

Keyword(s):

Microbial Communities ◽

Virulence Factors ◽

Human Microbiome ◽

Oral Microbiome ◽

Health State ◽

Important Process ◽

Cultivable Bacteria ◽

Cardio Vascular Disease ◽

Cardio Vascular ◽

Systemic Infections

The human body supports the growth of a wide array of microbial communities in various niches, such as the oral cavity, gastro-intestinal and urogenital tracts and on the surface of the skin. These host associated microbial communities include yet-un-cultivable bacteria and are influenced by various factors. Together, these communities of bacteria are referred to as the human microbiome. Human oral microbiome consists of both symbionts and pathobionts. Deviation from symbiosis among the bacterial community leads to “dysbiosis”—a state of community disturbance. Dysbiosis occurs due to many confounding factors that predispose to a shift in the composition and relative abundance of microbial communities. Dysbiotic communities have been a major cause for many microbiomes related systemic infections. Such dysbiosis is directed by certain important pathogens called the “keystone pathogens” that could modulate community microbiome variations. One such persistent infection is oral infection, mainly periodontitis, where a wide array of causal organisms has been implied to systemic infections such as cardio vascular disease, diabetes mellitus, rheumatoid arthritis and Alzheimer’s disease. The keystone pathogens co-occur with many yet-cultivable bacteria and their interactions lead to dysbiosis. This has been the focus of recent research. While immune evasion is one of the major modes that lead to dysbiosis, new processes and new virulence factors of bacteria have been shown to be involved in this important process of that determine disease or health state. This review focuses on such dysbiotic communities, their interactions and their virulence factors that predispose the host to other systemic implications.

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NamZ1 and NamZ2 from the oral pathogen Tannerella forsythia are peptidoglycan processing exo-β-N-acetylmuramidases with distinct substrate specificity

10.1101/2021.12.02.470905 ◽

2021 ◽

Author(s):

Marina Borisova ◽

Katja Balbuchta ◽

Andrew Lovering ◽

Alexander Titz ◽

Christoph Mayer

Keyword(s):

Cell Wall ◽

Oral Microbiome ◽

Periodontal Pathogen ◽

Nutrient Source ◽

Tannerella Forsythia ◽

Substrate Specificities ◽

Naturally Occurring ◽

Essential Growth ◽

Essential Growth Factor ◽

Broad Scale

ABSTRACTThe Gram-negative periodontal pathogen Tannerella forsythia is inherently auxotrophic for N-acetylmuramic acid (MurNAc), which is an essential carbohydrate constituent of the peptidoglycan (PGN) of the bacterial cell wall. Thus, to build up its cell wall, T. forsythia strictly depends on the salvage of exogenous MurNAc or sources of MurNAc, such as polymeric or fragmentary PGN, derived from cohabiting bacteria within the oral microbiome. In our effort to elucidate how T. forsythia satisfies its demand for MurNAc, we recognized that the organism possesses three putative orthologs of the exo-β-N-acetylmuramidase BsNamZ from Bacillus subtilis, which cleaves non-reducing end, terminal MurNAc entities from the artificial substrate pNP-MurNAc and the naturally-occurring disaccharide substrate MurNAc-β-1,4-N-acetylglucosamine (GlcNAc). TfNamZ1 and TfNamZ2 were successfully purified as soluble, pure recombinant His6-fusions and characterized as exo-lytic β-N-acetylmuramidases with distinct substrate specificities. The activity of TfNamZ1 was considerably lower compared to TfNamZ2 and BsNamZ, in the cleavage of pNP-MurNAc and MurNAc-GlcNAc. When peptide-free PGN glycans were used as substrates, we revealed striking differences in the specificity and mode of action of these enzymes, as analyzed by mass spectrometry. TfNamZ1, but not TfNamZ2 or BsNamZ, released GlcNAc-MurNAc disaccharides from these glycans. In addition, glucosamine (GlcN)-MurNAc disaccharides were generated when partially N-deacetylated PGN glycans from B. subtilis 168 were applied. This characterizes TfNamZ1 as a unique disaccharide-forming exo-lytic β-N-acetylmuramidase (exo-disaccharidase), and, TfNamZ2 and BsNamZ as sole MurNAc monosaccharide-lytic exo-β-N-acetylmuramidases.IMPORTANCETwo exo-β-N-acetylmuramidases from T. forsythia belonging to glycosidase family GH171 (www.cazy.org) were shown to differ in their activities, thus revealing a functional diversity within this family: NamZ1 releases disaccharides (GlcNAc-MurNAc/GlcN-MurNAc) from the non-reducing ends of PGN glycans, whereas NamZ2 releases terminal MurNAc monosaccharides. This work provides a better understanding of how T. forsythia may acquire the essential growth factor MurNAc by the salvage of PGN from cohabiting bacteria in the oral microbiome, which may pave avenues for the development of anti-periodontal drugs. On a broad scale, our study indicates that the utilization of PGN as a nutrient source, involving exo-lytic N-acetylmuramidases with different modes of action, appears to be a general feature of bacteria, particularly among the phylum Bacteroidetes.

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Human Remains

10.1017/9781316161654 ◽

2020 ◽

Author(s):

Margaret Clegg

Keyword(s):

Human Remains

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Collective Memory, Personal Pain: The Circulation of 9/11 Unidentified Human Remains

PsycEXTRA Dataset ◽

10.1037/e640762011-001 ◽

2010 ◽

Author(s):

Chip Colwell-Chanthaphonh ◽

Ventura Perez ◽

Heidi Bauer-Clapp

Keyword(s):

Collective Memory ◽

Human Remains

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Proteinase-inhibiting activity of an extract of Rumex acetosa L. against virulence factors of Porphyromonas gingivalis

Planta Medica ◽

10.1055/s-0033-1352210 ◽

2013 ◽

Vol 79 (13) ◽

Cited By ~ 1

Author(s):

S Beckert ◽

A Hensel

Keyword(s):

Porphyromonas Gingivalis ◽

Virulence Factors ◽

Inhibiting Activity ◽

Rumex Acetosa

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Enterococcal Virulence Determinants In Urinary Tract Infection Patients

Bangladesh Journal of Medical Microbiology ◽

10.3329/bjmm.v6i1.19361 ◽

2012 ◽

Vol 6 (1) ◽

pp. 14-17

Author(s):

Jabin Akhter ◽

Shaheda Anwar ◽

Sharmeen Ahmed

Keyword(s):

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Virulence Factors ◽

Virulence Determinants ◽

Microtitre Plate ◽

Microbiological Method ◽

Enterococcal Infection ◽

Microtitre Plate Assay ◽

Positive Frequency

Urinary tract infection caused by Enterococci has become frequent occurrences in health care settings. Currently they emerged with increasing resistance to multiple antibiotics. Haemolysin, gelatinase and biofilm production are some markers that have been proposed as possible Enterococcal virulence factors. In view of the increasing importance of Enterococcal infection, the present study was designed to isolate and identify the Enterococci to the species level from urine of urinary tract infection patients and to investigate their possible virulence factors. Biofilm was detected on polystyrene microtitre plate to see the adherence of microorganism. Haemolysin production and gelatin hydrolysis detected by standard microbiological method. Fifty nine enterococcal isolates were speciated by conventional microbiological method and examined for their ability to form biofilm by microtitre plate assay. In this study, biofilm formations by Enterococci were found in 83.33% isolates from catheterized and 56.09% from non-catheterized patients. Aong them, E.faecalis & 50% E.faecium produced biofilm. About 43.63% E.faecalis & 10% E.faecium produced haemolysin and only one isolate were found to be gelatinase positive. Frequency of virulence factors (VFs) in combination was observed in this study. Two VFs (haemolysin and biofilm) were observed in 27.11% in combination and 3 VFs ( haemolysinm biofilm and gelatinase) were present in 1.69% isolates. These results suggest that although there may not be an absolute role for individual virulence determinants in infectivity, combinations of factors may play a role in allowing a biofilm infection to be more resistant to therapy.DOI: http://dx.doi.org/10.3329/bjmm.v6i1.19361 Bangladesh J Med Microbiol 2012; 06(01): 14-17

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Three Cists from Tayvallich, Argyll

Glasgow Archaeological Journal ◽

10.3366/gas.1986.13.13.54 ◽

1986 ◽

Vol 13 (1) ◽

pp. 54-62 ◽

Cited By ~ 1

Author(s):

D Lehane

Keyword(s):

Human Remains

Summary Three cists were discovered during the rebuilding of a house in Tayvallich. They appear to have been inserted into a roughly oval pit. All three cists contained cremated human remains and Cist 3 also contained a food vessel with beaker affinities. Lithics from among the cairn material appear to be a redeposited Mesolithic assemblage.

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