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Various Bacterial Species (various + bacterial_species)
Selected AbstractsBacterial synthesis of biodegradable polyhydroxyalkanoatesJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007R.A.J. Verlinden Summary Various bacterial species accumulate intracellular polyhydroxyalkanoates (PHAs) granules as energy and carbon reserves inside their cells. PHAs are biodegradable, environmentally friendly and biocompatible thermoplastics. Varying in toughness and flexibility, depending on their formulation, they can be used in various ways similar to many nonbiodegradable petrochemical plastics currently in use. They can be used either in pure form or as additives to oil-derived plastics such as polyethylene. However, these bioplastics are currently far more expensive than petrochemically based plastics and are therefore used mostly in applications that conventional plastics cannot perform, such as medical applications. PHAs are immunologically inert and are only slowly degraded in human tissue, which means they can be used as devices inside the body. Recent research has focused on the use of alternative substrates, novel extraction methods, genetically enhanced species and mixed cultures with a view to make PHAs more commercially attractive. [source] Bleeding on probing differentially relates to bacterial profiles: the Oral Infections and Vascular Disease Epidemiology StudyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2008Ryan T. Demmer Abstract Aim: Various bacterial species are differentially prevalent in periodontal health, gingivitis or periodontitis. We tested the independent associations between three bacterial groupings and gingival inflammation in an epidemiological study. Material and Methods: In 706 Oral Infections and Vascular Disease Epidemiology Study (INVEST) participants 55 years, bleeding on probing (BoP), pocket depth (PD) and subgingival plaque samples (n=4866) were assessed in eight sites per mouth. Eleven bacterial species were quantitatively assayed and grouped as follows: (i) aetiologic burden (EB, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia); (ii) putative burden (PB, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Micromonas micros, Prevotella intermedia); (iii) health-associated burden (HAB, Actinomyces naeslundii, Veillonella parvula). Results: After mutual adjustment for EB, PB and HAB, the BoP prevalence increased by 45% ( p<0.0001) across increasing quartiles of EB while BoP decreased by 13% ( p<0.0001) across increasing quartiles of HAB. Mean PD increased 0.8 mm and decreased 0.3 mm from the first to fourth quartiles of EB (p<0.0001) and HAB ( p<0.0001), respectively. Among 1214 plaque samples with fourth quartile EB, 60% were collected from sites with PD 3 mm. Conclusion: Bacterial species believed to be aetiologically related to periodontitis were associated with BoP in sites with minimal PD and/or attachment level (AL). Species presumed to be associated with periodontal health demonstrated inverse associations with BoP. [source] Isolation and identification of mixed linked , -glucan degrading bacteria in the intestine of broiler chickens and partial characterization of respective 1,3-1,4- , -glucanase activitiesJOURNAL OF BASIC MICROBIOLOGY, Issue 3 2006Lutz Beckmann Media with 1,3-1,4- , -glucans as selective markers were used for isolation of non-starch-polysaccharide (NSP) degrading bacteria from the intestinal tract of broiler chicken. Formerly unknown 1,3-1,4- , endoglucanase activities in various bacterial species were identified in this study. E. faecium , Streptococcus , Bacteroides and Clostridium strains seem to be responsible for degradation of mixed linked , -glucans in the small intestine and in the hind gut of chickens. Strict anaerobic bacteria (Bacteroides ovatus , B. uniformis , presumably B. capillosus and Clostridium perfringens ) as well as an unidentified bacterium with 98% 16S rDNA homology to an uncultered chicken cecum bacterium were isolated. Additionally, Streptococcus bovis with 1,3-1,4- , -endoglucanase activity was also detected. Different 1,3-1,4- , -endoglucanase activity profiles were observed in SDS/PAGE zymograms. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Evaluation of the relationship between smoking during pregnancy and subgingival microbiotaJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2005Nurcan Buduneli Abstract Background: Numerous studies have shown that smoking negatively affects periodontal health. Hormonal changes, which occur during pregnancy have also been reported to have adverse effects on the periodontal tissues or indirectly through alterations in the subgingival bacterial flora. At present, no knowledge exists concerning possible effects of smoking on the composition of subgingival plaque in pregnancy. The purpose of the present study was to evaluate the effects of smoking during pregnancy on the subgingival plaque bacteria most commonly associated with periodontal disease. Methods: A total number of 181 women were examined within 72 h post-partum. Smoking status was recorded by means of a self-reported questionnaire and the study population was divided into three groups; non-smokers, light smokers, and heavy smokers. In each woman, two subgingival plaque samples were obtained from mesio- or disto-buccal aspect of randomly selected one molar and one incisor tooth by sterile paperpoints. Clinical periodontal recordings comprising presence of dental plaque, bleeding on probing (BOP), and probing pocket depth (PPD) were performed at six sites per each tooth at all teeth. Plaque samples were analysed by checkerboard DNA,DNA hybridization with respect to 12 bacterial species. In all analyses, the individual subject was the computational unit. Thus, mean values for all clinical parameters were calculated and bacterial scores from each individual sample were averaged. Statistical methods included ,2 test, Kruskal,Wallis test and Mann,Whitney U -test. Results: Mean ages were similar in the study groups. Plaque, BOP and PPD recordings were lower in the heavy-smoker group, but the differences were not statistically significant (p>0.05). The detection rates and bacterial loads of the specific subgingival bacteria exhibited no significant differences between the groups. No correlation could be found between smoking status and detection rates and bacterial loads of various bacterial species. Conclusion: The present findings suggest that smoking during pregnancy does not have a significant effect on the composition of subgingival plaque bacteria. [source] Presentation of functional organophosphorus hydrolase fusions on the surface of Escherichia coli by the AIDA-I autotransporter pathwayBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2008Chaokun Li Abstract We report, the surface presentation of organophosphorus hydrolase (OPH) and green fluorescent protein (GFP) fusions by employing the adhesin-involved-in-diffuse-adherence (AIDA-I) translocator domain as a transporter and anchoring motif. The surface location of the OPH,GFP fusion protein was confirmed by immunofluorescence microscopy, and protease accessibility, followed by Western blotting analysis. The investigation of growth kinetics and stability of resting cultures showed that the presence of the AIDA-I translocator domain in the outer membrane neither inhibits cell growth nor affects cell viability. Furthermore, the surface-exposed OPH,GFP was shown to have enzymatic activity and a functional fluorescence moiety. These results suggest that AIDA-I autotransporter is a useful tool to present heterologous macromolecule passenger proteins on the bacterial surface. Our strategy of linking GFP to OPH and the possibility to employ various bacterial species as host has enormous potential for enhancing field use. Biotechnol. Bioeng. 2008;99: 485,490. © 2007 Wiley Periodicals, Inc. [source] | ||||||||||