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Author (up) Bercik, P. file  url
  Title The microbiota-gut-brain axis: learning from intestinal bacteria? Type Journal Article
  Year 2011 Publication Gut Abbreviated Journal Gut  
  Volume 60 Issue 3 Pages 288-289  
  Keywords Animals; Bacterial Infections/*psychology; Cognition Disorders/*microbiology; Humans; Intestinal Diseases/microbiology/*psychology; Intestines/*microbiology; Mice; Symbiosis; Microbiome  
  Abstract The intestinal microbiota is a diverse and dynamic ecosystem,1 which has developed a mutualistic relationship with its host and plays a crucial role in the development of the host's innate and adaptive immune responses.2 This ecosystem serves the host by protecting against pathogens, harvesting otherwise inaccessible nutrients, aiding in neutralisation of drugs and carcinogens, and affecting the metabolism of lipids.3 Gut bacteria modulate intestinal motility, barrier function and visceral perception.4

An interaction between the intestinal microbiota and the central nervous system (CNS) may seem difficult to conceive at first sight, but clinicians are well aware of the benefit of oral antibiotics and laxatives in the treatment of hepatic encephalopathy.5 Data accumulated from animal studies indicate that there is central sensing of gastrointestinal infections. For example, acute infection with Campylobacter jejuni results in anxiety-like behaviour and rapid activation of vagal pathways prior to onset of immune responses,6 while chronic Helicobacter pylori infection in mice leads to abnormal feeding behaviour and upregulation of tumour necrosis factor α (TNFα) in the median eminence of the hypothalamus.7 Rapid and sustained gut�brain communication may confer a significant advantage to the host, as central activation in response to changes in commensals or pathogens would allow better control of gut function and immunity.
  Call Number Serial 2096  
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Author (up) Fuqua, C.; Greenberg, E.P. file  url
doi  openurl
  Title Listening in on bacteria: acyl-homoserine lactone signalling Type Journal Article
  Year 2002 Publication Nature Reviews. Molecular Cell Biology Abbreviated Journal Nat Rev Mol Cell Biol  
  Volume 3 Issue 9 Pages 685-695  
  Keywords 4-Butyrolactone/*analogs & derivatives/biosynthesis/chemistry/*metabolism; Animals; Bacteria/cytology/enzymology/*metabolism/pathogenicity; Biofilms; Bioterrorism; Luminescent Measurements; Repressor Proteins/chemistry/genetics/metabolism; *Signal Transduction; Symbiosis; Trans-Activators/chemistry/genetics/metabolism  
  Abstract Bacterial cell-to-cell signalling has emerged as a new area in microbiology. Individual bacterial cells communicate with each other and co-ordinate group activities. Although a lot of detail is known about the mechanisms of a few well-characterized bacterial communication systems, other systems have been discovered only recently. Bacterial intercellular communication has become a target for the development of new anti-virulence drugs.  
  Call Number Serial 96  
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Author (up) Ghimire, S.R.; Charlton, N.D.; Bell, J.D.; Krishnamurthy, Y.L.; Craven, K.D. url  doi
  Title Biodiversity of fungal endophyte communities inhabiting switchgrass (Panicum virgatum L.) growing in the native tallgrass prairie of northern Oklahoma Type Journal Article
  Year 2011 Publication Fungal Diversity Abbreviated Journal Fungal Diversity  
  Volume 47 Issue 1 Pages 19-27  
  Keywords Biodiversity; Bioenergy; Endophyte; Hypocreales; Mutualism; Symbiosis  
  Abstract This study was conducted to explore fungal endophyte communities inhabiting native switchgrass plants from the tallgrass prairie of northern Oklahoma. The primary focus was to isolate these endophytes in pure culture from surface-sterilized plant tissues and provide taxonomic identifications based on comparative analysis of ITS rDNA gene sequences. From these data, we evaluated the biodiversity of these potentially beneficial endosymbionts from this rapidly disappearing habitat of the Great Plains. While important from a strictly conservationist standpoint, this survey further allowed us to identify candidate endophytes for introduction into commercial switchgrass cultivars for biomass enhancement. A total of 210 whole plant samples were collected at early vegetative, full reproductive and senescence stages. Fungal endophytes were isolated, identified to species level when possible, and grouped into communities based on plant part, collection month and part of the prairie from which the plants were collected. Species diversity for each community was estimated by Shannon diversity index, and differences in diversity indices were compared using a t-test. The presence of fungal species representing at least 18 taxonomic orders suggests a high level of diversity in switchgrass endophyte communities. The fungal communities from shoot tissue had significantly higher species diversity than communities from the root tissue. The abundance of taxa assigned to the order Hypocreales (to which mutualistic, clavicipitaceous endophytes of cool-season grasses belong) found in shoot (64%) and root tissues (39%) throughout the growing season suggests great potential for utilizing these endophytes for enhancing biomass production and stress resistance of this important bioenergy crop.  
  Call Number Serial 977  
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Author (up) Gundel, P.E.; Helander, M.; Casas, C.; Hamilton, C.E.; Faeth, S.H.; Saikkonen, K. file  url
  Title Neotyphodium fungal endophyte in tall fescue (Schedonorus phoenix): a comparison of three Northern European wild populations and the cultivar Kentucky-31 Type Journal Article
  Year 2013 Publication Fungal Diversity Abbreviated Journal Fungal Diversity  
  Volume 60 Issue 1 Pages 15-24  
  Keywords Plant-microbial symbiosis; Grass Symbiosis; Vertically transmitted symbiont; Claviceps  
  Abstract Pooideae grasses may be colonized by systemic fungal endophytes. The fitness of endophyte depends entirely on resources and seed transmission from the host plant, while colonized plants may gain increased survival, growth, and reproduction relative to their uncolonized conspecifics. Most research of endophyte-grass interactions have been carried out on few cultivars of tall fescue (Schedonorus phoenix) and their symbiont Neotyphodium coenophialum. Lack of studies using wild populations of tall fescue across the species natural distribution range, however, limits the understanding of the ecological and evolutionary role of the symbiosis in nature. We performed a common garden experiment in Southern Finland with three wild, tall fescue populations from northern Europe and the forage cultivar Kentucky-31 (KY-31). For each population, we used naturally endophyte-colonized, naturally endophyte-colonized but endophyte removed (decolonized), and naturally uncolonized plants to separate effects due to the host genotype from the endophyte. We evaluated growth variables and survival in four environmental treatments of varying water and nutrients. Supply of water and nutrients increased plant biomass and reproductive effort in all populations. This effect was higher for KY-31 plants which produced on average 55% more seeds than wild plants, indicating better adaptation to high resource environments. However, the higher incidence of Claviceps sp. and the low winter survival indicated KY-31 tall fescue is mal-adapted to Northern European conditions. Naturally colonized plants had greater plant biomass (12%), reproductive effort (22%) and seed mass (29%) than naturally uncolonized and decolonized plants. Nonetheless, endophyte colonization did not affect plant survival, and the effects of endophyte colonization on tiller number, panicle/tiller ratio and Claviceps sp. incidence depended on the population origin. In the wild populations, endophyte removal only reduced the number of tillers (29 % lower), while the difference between naturally colonized and naturally uncolonized plants was not significant. Our results show that endophyte symbiont increases tall fescue performance in general, but the differences between wild populations and cultivars indicate adaptation to local habitats and agronomic management, respectively. The comparison of naturally endophyte-colonized and decolonized plants suggests certain plant genotype-endophyte combinations found within populations result from local selection pressures.  
  Call Number Serial 962  
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Author (up) Harrier, L.A.; Watson, C.A. file  url
  Title The potential role of arbuscular mycorrhizal (AM) fungi in the bioprotection of plants against soil-borne pathogens in organic and/or other sustainable farming systems Type Journal Article
  Year 2004 Publication Pest Management Science Abbreviated Journal Pest Manag Sci  
  Volume 60 Issue 2 Pages 149-157  
  Keywords Agriculture/*methods; Conservation of Natural Resources/methods; Health Food; Mycorrhizae/*growth & development; Plants/*microbiology; *Soil Microbiology; Symbiosis  
  Abstract Sustainable farming systems strive to minimise the use of synthetic pesticides and to optimise the use of alternative management strategies to control soil-borne pathogens. Arbuscular mycorrhizal (AM) fungi are ubiquitous in nature and constitute an integral component of terrestrial ecosystems, forming symbiotic associations with plant root systems of over 80% of all terrestrial plant species, including many agronomically important species. AM fungi are particularly important in organic and/or sustainable farming systems that rely on biological processes rather than agrochemicals to control plant diseases. Of particular importance is the bioprotection conferred to plants against many soil-borne pathogens such as species of Aphanomyces, Cylindrocladium, Fusarium, Macrophomina, Phytophthora, Pythium, Rhizoctonia, Sclerotinium, Verticillium and Thielaviopsis and various nematodes by AM fungal colonisation of the plant root. However, the exact mechanisms by which AM fungal colonisation confers the protective effect are not completely understood, but a greater understanding of these beneficial interactions is necessary for the exploitation of AM fungi within organic and/or sustainable farming systems. In this review, we aim to discuss the potential mechanisms by which AM fungi may contribute to bioprotection against plant soil-borne pathogens. Bioprotection within AM fungal-colonised plants is the outcome of complex interactions between plants, pathogens and AM fungi. The use of molecular tools in the study of these multifaceted interactions may aid the optimisation of the bioprotective responses and their utility within sustainable farming systems.  
  Call Number Serial 920  
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