Просмотр исходного текста страницы Microscopic-Evidence-Existence-Succession-Biofilm-Phenotypes-e

We submit that complex cell-cell interactions within prokaryotic communities are an ancient characteristic, the development of which was facilitated by the localization of cells at surfaces. In addition to spatial localization, surfaces may have provided the protective niche in which attached cells could create a localized homeostatic environment. In a holistic sense both biofilm and planktonic phenotypes may be viewed as integrated components of prokaryote life. Studies to control biofilm formation by coupling ultrasonication of natural The main objective of this study was to investigate the combined effect of ultrasonication of natural waters and anodization of titanium on microbial density and biofilm formation tendency on titanium surfaces. Application of 24 kHz, 400 W high power ultrasound through a 14 mm horn type SS (stainless steel) Sonicator with medium amplitude of 60% for 30 min brought about three order decrease in total bacterial density of laboratory tap water, cooling tower water and reservoir water and two order decrease in seawater. Studies on the effect of ultrasonication on dilute pure cultures of Gram-negative and Gram-positive bacteria showed five order and three order decrease for Pseudomonas sp.<br /><br /> and Flavobacterium sp. respectively and two order and less than one order decrease phase and reduced logarithmic population increase and specific growth rate of Gram-negative bacteria whereas for Gram-positive bacteria specific growth rate increased. Studies on the biofilm formation tendency of these ultrasonicated mediums on titanium surface showed one order reduction under all conditions. Detailed biofilm imaging by advanced microscopic techniques like AFM, SEM and epifluorescence microscopy clearly visualized the lysed/damaged cells and membrane perforations due to ultrasonication. Combination of ultrasonication and anodization brought about maximum decrease in bacterial density and biofilm formation with greater than two order decrease in seawater, two order decrease in Bacillus sp. culture and more than four order decrease in Flavobacterium sp. culture establishing the synergistic effect of anodization and ultrasonication Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas The opportunistic pathogen Pseudomonas aeruginosa produces colorful redox-active and clinical outcomes.<br /><br /> Although phenazines exist in many forms, the best studied uncharacterized protein that oxidizes the pyocyanin methyl group to formaldehyde and reduces the pyrazine ring via an unusual tautomerizing demethylation reaction. Treatment with PodA disrupts P. aeruginosa biofilm formation similarly to DNase, suggesting interference with the pyocyanin-dependent release of extracellular DNA into the matrix. PodA-dependent pyocyanin demethylation also restricts established biofilm aggregate populations experiencing anoxic conditions. Together, these results show that modulating extracellular redox-active metabolites can influence the fitness of a biofilm-forming Effects of short-time exposure of surface pre-reacted glass-ionomer eluate on This study evaluated the antibacterial effects of short-time exposure of surface pre-reacted glass-ionomer (S-PRG) eluate on oral microcosm biofilm. [http://atlas.dustforce.com/user/wolfraven01 polysaccharide] were treated with an S-PRG eluate at different concentrations (25%, 50%, and 100%), distilled water (DW), and 0% chlorhexidine (CHX) twice a day for 5&nbsp;min repeatedly. After 7 days, the total and aciduric bacterial counts and biofilm dry weights were measured.<br /><br /> An image analysis program calculated the red/green&nbsp;(R/G) ratios in the biofilm autofluorescence images. Microscopic analyses quantified the biofilm thickness and live/dead cell ratio and determined morphological changes in the biofilm. Bacterial counts and dry weights were not significantly different in the DW group for all S-PRG eluate concentrations. An increasing trend in the R/G ratio for 7 days biofilm treatment was observed for the S-PRG eluate and the DW groups. Furthermore, the live/dead cell ratios in the biofilm and the biofilm thickness of the S-PRG eluate groups were similar to those of the DW group. [https://peatix.com/user/21101131 https://peatix.com/user/21101131] inside the biofilm changed only in the CHX group. [https://www.longisland.com/profile/stampbridge74 https://www.longisland.com/profile/stampbridge74] -time S-PRG eluate treatment showed no significant antibacterial and antibiofilm effects.<br /><br /> These results indicated that limited biofilm formation inhibition can be obtained by Conflict of interest statement: The S-PRG eluate was provided by Shofu Inc., Kyoto, Japan; however, the authors state to have no financial relationship with this company, and declare no conflicts of interest.