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Factors Controlling the Microflora of the Healthy Mouth
Published in Michael J. Hill, Philip D. Marsh, Human Microbial Ecology, 2020
The motile rods of dental plaque are conspicuous in dark field or phase contrast microscopy of wet mounts of plaque samples.49 Several species of oral, Gram-negative rods are motile by means of flagella. Among these are the microaerophilic Campylobacter sputorum and C. concisus, which are curved rods with a single, polar flagellum.81Wolinellarecta and W. curva are anaerobic, Gram-negative rods also having a single flagellum;82 they may previously have been identified as oral Vibrio species. Selenomonas sputigena is a curved to helical, Gram-negative, anaerobic rod with a tuft of flagella near the center of the concave side. Another motile, curved or helical, Gram-negative, anaerobic rod has been characterized recently as Centipeda periodontii. It has 50 or more flagella located in a linear zone, which spirals around the cell, and it shows spreading growth on the surface of blood agar.83,84 Other types of motility than that mediated by flagella are the gliding movement of Capnocytophaga species and the twitching motility of B. gracilis and B. ureolyticus.
Lipopolysaccharide from Oral Bacteria: Role in Innate Host Defense and Chronic Inflammatory Disease
Published in Helmut Brade, Steven M. Opal, Stefanie N. Vogel, David C. Morrison, Endotoxin in Health and Disease, 2020
Brian W. Bainbridge, Richard P. Darveau
The polysaccharide portions of the LPS molecules of oral bacteria are not as well characterized as those of enterobacteria. Although detailed structural information on the core region is not available, it is apparent from compositional analysis that the core of many oral LPS vary from enterobacteria as well as from one another. This is particularly apparent from the presence of unusual components such as D-glycero-D-mannoheptose in species such as A. actinomycetemcomitans and C. rectus and phosphorylated KDO in P. gingivalis and P. intermedia (15,18,27,29). From the compositional data given in Table 2, it appears that the common constituent sugars in the oral LPS examined are rhamnose, fucose, glucose, galactose, mannose, glucosamine, galactosamine, KDO, and heptose. This small number of component sugars suggests that the strains examined have O-polysaccharide chains consisting of these sugars as well or, alternatively, are lacking in O-polysaccharide repeating units. C. rectus strain 33238, for example, is known to have a repeating unit consisting exclusively of rhamnose (18). LPS from 12 selected strains of P. gingivalis all contained the sugars rham-nose, mannose, glucose, galactose, glucosamine, and galactosamine, with one strain also containing fucose, suggesting that there is not the high degree of variability in the polysaccharide portion of P. gingivalis LPS that there is in many enterobacterial species (23,24,28,29). Selenomonas sputigena is known to have a repeating unit consisting of galactose and glucosamine (34). F. nucleatum strain JCM 8532, on the other hand, was found to have an O-polysaccharide consisting of the less common D-quinovosamine (19). And although the most pathogenic serotype of A. actinomycetemcomitans was found to have an O-polysaccharide having the repeating structure (-3-α-D-Fuc-(1→2)-α-L-Rha-(3→1)-(β-D-GalNAc), other serotypes contained repeating structures of deoxy-L-talose or deoxy-D-talose (16,17). It therefore appears that in general there maybe less diversity in the O side chain composition found in LPS obtained from oral species. The significance of this observation is not fully understood.
Sex-specific differences in the salivary microbiome of caries-active children
Published in Journal of Oral Microbiology, 2019
Stephanie Ortiz, Elisa Herrman, Claudia Lyashenko, Anne Purcell, Kareem Raslan, Brandon Khor, Michael Snow, Anna Forsyth, Dongseok Choi, Tom Maier, Curtis A. Machida
Conversely, for caries-free children, Lachnospiraceae [G-3] species HOT 100 and Bergeyella species HOT 900 were found in significantly higher levels in caries-free boys than caries-free girls, exhibiting 39.5 and 21.8-fold differences, respectively (Table 3). In addition, Selenomonas noxia, Prevotella micans, Prevotella oralis, Actinomyces species HOT 170, Aggregatibacter species HOT 949, Leptotrichia species HOT 218, Oribacterium species HOT 078, Leptotrichia species HOT 498, Actinomyces species HOT 171, Streptococcus anginosos, Leptotrichia wadei, Prevotella pleuritidis, Cardiobacterium genus probe, Selenomonas sputigena, and Actinomyces naeslundii were found at significantly higher levels in caries-free girls than caries-free boys, exhibiting 357-, 299-, 206-, 159-, 137-, 102-, 87.3-, 78.7-, 69.4-, 49.4-, 37.4-, 28.7-, 28.6-, 26.8-, and 16.9-fold differences, respectively (Table 3).
Xylitol and sorbitol effects on the microbiome of saliva and plaque
Published in Journal of Oral Microbiology, 2019
Reisha Rafeek, Christine V. F. Carrington, Andres Gomez, Derek Harkins, Manolito Torralba, Claire Kuelbs, Jonas Addae, Ahmed Moustafa, Karen E. Nelson
Accordingly, PCA based on the microbial profiles of the 230 samples, at the species (OTU) level (Figure 3(a,b)), indicated strong clustering primarily according to whether the sample was saliva or plaque (see also Figure A1), with most variance explained by species within the phyla Firmicutes (S. vestibularis, S. parasanguinis, Veillonella sp. oral taxon 158, S. peroris, Oribacterium sinus, V. dispar, Selenomonas sputigena, Eubacterium infirmum, Se. sp oral taxon 149), Actinobacteria (Rothia mucilaginosa, Actinomyces graevenitzii, Corynebacterium matruchotii, R. aeria), Bacteriodetes (Prevotella sp. oral taxon 299, P. pallens), Fusobacteria (Leptotrichia hofstadii) and Proteobacteria (Neisseria mucosa, N. elongate, N. subflava, Lautropia mirailis) (Figure 3(c,d)). The differences between saliva and plaque were greater than those driven by study group A and B (Figures 3(b) and A1) indicating that random allocation to groups was not a bias.
Association of nine pathobionts with periodontitis in four South American and European countries
Published in Journal of Oral Microbiology, 2023
Gerard Àlvarez, Alexandre Arredondo, Sergio Isabal, Wim Teughels, Isabelle Laleman, María José Contreras, Lorena Isbej, Enrique Huapaya, Gerardo Mendoza, Carolina Mor, José Nart, Vanessa Blanc, Rubén León
The use of methods like culture or DNA–DNA hybridisation first associated periodontitis with bacteria such as Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola [5]. Soon thereafter, species like Filifactor alocis, Selenomonas sputigena, Porphyromonas endodontalis and Treponema socranskii were also related to periodontitis using PCR [6]. Nonetheless, the advent of high-throughput sequencing (HTS) allowed for the comparison of whole microbial communities, confirming previous observations [7,8], stressing the importance of species like F. alocis or P. endodontalis [9,10], and describing new putative periodontopathogens such as Fretibacterium fastidiosum and Eubacterium brachy [9,10]. The use of HTS, mainly 16S metagenomics, unveiled a complex scenario where periodontitis was seen to result not from individual pathogens but rather from polymicrobial synergy and dysbiosis [3,4,7]. Most of the above-mentioned publications are single-country studies from a rather low number of countries (to our knowledge, about 55% used samples from the USA, 14% from Brazil, and the remaining percentage of publications used samples from the following countries in an equal distribution: Germany, the UK, Spain, Italy, Sweden, Turkey, China, Japan, Korea, Taiwan, Saudi Arabia, United Arab Emirates, India and Chile) [7,9,11]. However, it should be considered that microbial composition can be influenced by host genotype, environment and habits [9]. In fact, one study showed significant microbial divergence between African Americans and Caucasians who shared geographic location, lifestyle and nutrition [12]. Therefore, different human populations and ethnicities can harbour different microbiota.