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Dental Disease, Inflammation, Cardiovascular Disease, Nutrition and Nutritional Supplements
Published in Stephen T. Sinatra, Mark C. Houston, Nutritional and Integrative Strategies in Cardiovascular Medicine, 2022
Douglas G. Thompson, Gregori M. Kurtzman, Chelsea Q. Watkins
Formation of the biofilm includes a series of steps that begins with the initial colonization of the pellicle through adsorption of bacterial molecules creating an adhesive layer on the tooth surface. This leads to other diverse bacterial species’ co-adhesion using bacterial receptors to create diversity. There are both synergistic and antagonistic biochemical interactions among the inhabitants of the pellicle. Those bacteria continue to divide until a three-dimensional mixed-culture biofilm forms that is specially and functionally organized with polymer production leading to development of an extracellular matrix. This matrix is a key structural aspect of the biofilm offering the inhabitants protection from external factors. As the biofilm matrix thickens and microbiome becomes more mature, anaerobic bacteria are able to live deeper within the biofilm, and with the biofilm and aerobic bacteria further protecting them from the oxygen-rich environment within the oral cavity they survive in. The early biofilm is able to withstand frequent mechanisms of oral bacterial removal such as chewing, swallowing and salivary fluid flow. Early biofilm colonizers are also able to survive in the high oxygen concentrations present in the oral cavity. This initial biofilm is always present orally, forming immediately after oral cleansing (toothbrushing) by the patient.
Acinetobacter — Microbiology
Published in E. Bergogne-Bénézin, M.L. Joly-Guillou, K.J. Towner, Acinetobacter, 2020
Colonies of Acinetobacter spp. on solid media are generally smooth, sometimes mucoid, and comparable in size to those of enterobacteria (see Figure 1.3). Glucose-non-acidifying strains usually grow with smaller colonies than the glucose-acidifying groups. The colour of colonies may vary from pale yellow to greyish. Environmental strains that produce a diffusible brown pigment have been described (Pagel and Seyfried, 1976). In fluid media, e.g., nutrient broth, acinetobacters grow homogeneously with variation in turbidity. A pellicle or ring on the vessel wall at the surface of the medium can sometimes be seen, which is probably associated with the adhering properties of the strains.
Factors Controlling the Microflora of the Healthy Mouth
Published in Michael J. Hill, Philip D. Marsh, Human Microbial Ecology, 2020
An important factor in colonization is the saliva- and serum-derived proteins which coat oral epithelial and hard tissue surfaces as well as the bacteria within a few seconds. On the teeth this 1- to 10-μm surface film is called the acquired pellicle. Several proteins, which may be involved in bacterial adherence and aggregation (glycoproteins, blood group reactive substances, amylase, lysozyme, IgA, IgG, and albumin) have been identified in the pellicle.129,30 Salivary proteins modify colonization in a complex way, as they not only may promote adherence and aggregation on oral surfaces of certain microorganisms, but also enhance oral clearance of microorganisms by aggregating them in saliva into clumps, which are swallowed.
Interaction between microorganisms and dental material surfaces: general concepts and research progress
Published in Journal of Oral Microbiology, 2023
Yan Tu, Huaying Ren, Yiwen He, Jiaqi Ying, Yadong Chen
Acquired pellicle formation: All thesurfaces exposed to the oral environment are stably covered with a thin film composed of organic and inorganic molecules adsorbed to teeth, resin composites, and dentures. These molecules mainly originate from saliva and serve as bacterial receptors.Reversible adhesion: Brownian motion and salivary flow can lead to the initial transport of individual microbial cells or microbial aggregates to the nearby solid matrix. This stage involves weak, long-distance, and reversible physicochemical interactions.Irreversible adhesion: This stage includes the formation of a strong anchoring force by specific interactions between bacteria and the surface, such as covalent, ionic, or hydrogen bonds.Coadhesion and mature biofilm formation: In the last stage, secondary colonizing bacteria adhere to the receptors of attached microorganisms, resulting in biofilm development and proliferation.
Effects of dam and seqA genes on biofilm and pellicle formation in Salmonella
Published in Pathogens and Global Health, 2018
Sinem Uğur, Nefise Akçelik, Fatma Neslihan Yüksel, Neslihan Taşkale Karatuğ, Mustafa Akçelik
All wild-type and mutant strains were evaluated for their pellicle forming abilities. Physical features of pellicle (rigid, fragile and elastic), media turbidity, pellet at the bottom of the test tube and formation of ring structure between liquid-air interface were also visually evaluated after 8 days of incubation. When the properties of the pellicle formation in the liquid-air intermediate phase were examined, it was found that pellicle formation was observed in the all tested serovars of DMC2 (S. Group C1), DMC4 (S. Typhimurium), DMC11 (S. Virchow), DMC22 (S. Enteritidis) and DMC89 (S. Montevideo) (p < 0.05). The ability to form a pellicle in the dam and seqA mutants of the same serovar was lost. On the other hand, parallel to the results obtained from biofilm formation characteristics on polystyrene surface, after transferring the pBAD24 vector containing the dam and seqA genes to the dam and seqA mutants, it was determined that if these transformants were induced in the presence of 0.01% arabinose, the ability of pellicle formation was regained (p < 0.05) (Figure 4).
Effect of reserpine on Pseudomonas aeruginosa quorum sensing mediated virulence factors and biofilm formation
Published in Biofouling, 2018
Debaprasad Parai, Malabika Banerjee, Pia Dey, Arindam Chakraborty, Ekramul Islam, Samir Kumar Mukherjee
Pellicle formation was assessed as described earlier (Friedman and Kolter 2004). Briefly, 5 ml of LB containing 0.5% glucose were inoculated with P. aeruginosa PAO1 in glass tubes (18 mm × 150 mm, Borosil®, Borosil Glass Works Ltd., Kolkata, India). The IC25, IC50 and IC80 of reserpine were added to the treatment sets and the same proportions of DMSO were added to the control sets. The tubes were incubated vertically at 37°C without any mechanical shaking. Pellicle formation at the air–liquid interface was visually observed after 72 h.