Search results for "bacteria."
showing 10 items of 4757 documents
Assembly and functioning of endophytic bacterial communities in arcto-alpine pioneer plant Oxyria digyna
2019
Plant microbiomes consist of diverse communities of microorganisms, among which bacteria are highly abundant. The microbiomes are crucial for plants as they rely on their microbial associates for many essential functions. The goal of this thesis was to study the functional diversity and assembly rules of endophytic bacterial communities in different plant tissues of the arcto-alpine pioneer plant species, Oxyria digyna. I used high-throughput sequencing and bacterial isolations to characterize the endophytic communities in the leaves and roots of native O. digyna plants (wild plants) and micropropagated aseptic plants (bait plants) in the field. Wild plants and tissue-propagated bait plants…
Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR
2011
Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…
Extending the hosts of Tectiviridae into four additional genera of Gram-positive bacteria and more diverse Bacillus species
2018
Tectiviridae are composed of tailless bacteriophages with an icosahedral capsid and an inner membrane enclosing a double-stranded 15 kb linear DNA genome. Five of the seven previously studied Tectivirus isolates infect bacteria from Bacillus cereus sensu lato group (Betatectivirus), one distantly related member (PRD1) infect Enterobactericeae (Alpatectivirus) and one recently discovered virus infect Gluconobacter cerinus (Gammatectivirus). Here we expand the host spectrum of Betatectivirus elements to four additional genera (Streptococcus, Exiguobacterium, Clostridium and Brevibacillus) and to more distantly related Bacillus species (B. pumilus and B. flexus) by studying the genomes of four…
Conserved histidine and tyrosine determine spectral responses through the water network in Deinococcus radiodurans phytochrome
2022
Funding Information: This work was supported by Academy of Finland grants 285461 (H.T.), 330678 (H.T., J.R.), 277194 (H.L.), and 290677 (S.M.). We acknowledge the European Synchrotron Radiation Facility (ESRF) for providing synchrotron access for crystal data collection. We thank Prof. Janne Ihalainen (University of Jyväskylä) for all the help in all aspects of the paper, Prof. Gerrit Groenhof (University of Jyväskylä) for support, and Prof. Nikolai V. Tkachenko (Tampere University) for help and facilities for time-resolved absorption spectroscopy. We also thank M.Sc. Alli Liukkonen (University of Jyväskylä) and Dr. Heikki Häkkänen (University of Jyväskylä) for the assistance in laboratory …
Supramolecular Hydro- and Ionogels: A Study of Their Properties and Antibacterial Activity.
2017
Diimidazolium-based organic salts, bearing peptides or amino acids as anions have been synthesised and tested for their gelling ability in biocompatible solvents. These low molecular weight salts were successfully used as gelators in phosphate buffered saline (PBS) solution and ionic liquids. Then, the properties of the obtained soft materials were analysed in terms of melting temperature and gel strength as accounted for by rheological investigations. The gel-phase formation was studied by using UV/Vis and resonance light scattering measurements, whereas the morphology of the soft materials was analysed by using polarised optical microscopy and scanning electron microscopy. To get informat…
Advanced Strategies for Food-Grade Protein Production: A New
2019
Food-grade production of recombinant proteins in Gram-positive bacteria, especially in LAB (i.e., Lactococcus, Lactobacillus, and Streptococcus), is of great interest in the areas of recombinant enzyme production, industrial food fermentation, gene and metabolic engineering, as well as antigen delivery for oral vaccination. Food-grade expression relies on hosts generally considered as safe organisms and on clone selection not dependent on antibiotic markers, which limit the overall DNA manipulation workflow, as it can be carried out only in the expression host and not in E. coli. Moreover, many commercial expression vectors lack useful elements for protein purification. We constructed a “sh…
Midbiotics : conjugative plasmids for genetic engineering of natural gut flora
2019
ABSTRACTThe possibility to modify gut bacterial flora has become an important goal, and various approaches are used to achieve desirable communities. However, the genetic engineering of existing microbes in the gut, which are already compatible with the rest of the community and host immune system, has not received much attention. Here, we discuss and experimentally evaluate the possibility to use modified and mobilizable CRISPR-Cas9-endocing plasmid as a tool to induce changes in bacterial communities. This plasmid system (briefly midbiotic) is delivered from bacterial vector into target bacteria via conjugation. Compared to, for example, bacteriophage-based applications, the benefits of c…
Efficacy of different concentrations of sodium hypochlorite and chlorhexidine in disinfection of contaminated Resilon cones.
2011
Objectives: The aim of this study was to evaluate the effectiveness of different concentrations of Chlorhexidine (CHX) and sodium hypochlorite (NaOCl) in disinfecting contaminated Resilon cones within one minute. Study design: Fifty Resilon cones were divided into seven experimental groups and three control groups of 5 cones each. The cones of experimental groups were contaminated with Entrococcus faecalis and subsequently disinfected with different concentrations of NaOCl or CHX. The cones were then transferred into glass tubes containing thioglycollate media and incubated for 7 days. The tubes were examined for turbidity every 24 hours, and if bacterial growth occurred, samples were plate…
Silver nanoparticles in resin luting cements: antibacterial and physiochemical properties
2016
Background Silver has a long history of use in medicine as an antimicrobial and anti-inflammatory agent. Silver nanoparticles (NAg) offer the possibility to control the formation oral biofilms through the use of nanoparticles with biocidal, anti-adhesive, and delivery abilities. This study aims to evaluate the antibacterial effect of resin luting cements with and without NAg, and their influence on color, sorption and solubility. Material and methods NAg were incorporated to two dual-cured resin cements (RelyX ARC (RA) color A1 and RelyX U200 (RU) color A2) in two concentrations (0.05% and 0.07%, in weight), obtaining six experimental groups. Disc specimens (1x6mm) were obtained to verify t…
Additional file 2: Table S1. of Coinfection outcome in an opportunistic pathogen depends on the inter-strain interactions
2017
Effect of the treatment (single or coinfection) on the growth parameters of Flavobacterium columnare. (DOC 29Â kb)