Journal Articles

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    Chitin Deacetylases Are Required for Epichloë festucae Endophytic Cell Wall Remodeling During Establishment of a Mutualistic Symbiotic Interaction with Lolium perenne
    (The American Phytopathological Society in cooperation with the International Society for Molecular Plant-Microbe Interactions, 2021-10-28) Noorifar N; Savoian MS; Ram A; Lukito Y; Hassing B; Weikert TW; Moerschbacher BM; Scott B
    Epichloë festucae forms a mutualistic symbiotic association with Lolium perenne. This biotrophic fungus systemically colonizes the intercellular spaces of aerial tissues to form an endophytic hyphal network and also grows as an epiphyte. However, little is known about the cell wall-remodeling mechanisms required to avoid host defense and maintain intercalary growth within the host. Here, we use a suite of molecular probes to show that the E. festucae cell wall is remodeled by conversion of chitin to chitosan during infection of L. perenne seedlings, as the hyphae switch from free-living to endophytic growth. When hyphae transition from endophytic to epiphytic growth, the cell wall is remodeled from predominantly chitosan to chitin. This conversion from chitin to chitosan is catalyzed by chitin deacetylase. The genome of E. festucae encodes three putative chitin deacetylases, two of which (cdaA and cdaB) are expressed in planta. Deletion of either of these genes results in disruption of fungal intercalary growth in the intercellular spaces of plants infected with these mutants. These results establish that these two genes are required for maintenance of the mutualistic symbiotic interaction between E. festucae and L. perenne.
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    Symbiosal® and lowering of blood pressure and reduced risk of hypertension: evaluation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006
    (John Wiley and Sons Ltd on behalf of European Food Safety Authority, 2018-07-25) EFSA Panel on Dietetic Products, Nutrition and Allergies (EFSA NDA Panel); Turck D; Bresson J-L; Burlingame B; Dean T; Fairweather-Tait S; Heinonen M; Hirsch-Ernst KI; Mangelsdorf I; McArdle HJ; Naska A; Neuhäuser-Berthold M; Nowicka G; Pentieva K; Sanz Y; Sjödin A; Stern M; Tomé D; Van Loveren H; Vinceti M; Willatts P; Martin A; Strain SJJ; Siani A
    Following an application from Han-Biotech GmbH, submitted for authorisation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006 via the Competent Authority of Germany, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Symbiosal®, lowering of blood pressure and reduced risk of hypertension. The Panel considers that the food, Symbiosal®, which is the subject of the health claim, and the food, table salt, which Symbiosal® should replace, are sufficiently characterised. Lowering of blood pressure is a beneficial physiological effect. Increased blood pressure is a risk factor for hypertension. In weighing the evidence, the Panel took into account that one human study with some methodological limitations showed an effect of Symbiosal® on blood pressure in the context of a self-selected diet with a maximum of 3 g/day added salt. The Panel also took into account that no other human studies in which these results have been replicated were provided, that the animal studies did not support the results of the human study, that no evidence was provided in support of a mechanism by which Symbiosal® could induce a decrease in blood pressure upon oral consumption as compared to table salt in vivo in humans, and the low biological plausibility of the effect observed in the human intervention study. The Panel concludes that a cause and effect relationship has not been established between the consumption of Symbiosal® and lowering of blood pressure.