The Vitamin B1 Metabolism of Staphylococcus aureus Is Controlled at Enzymatic and Transcriptional Levels

Vitamin B1 is in its active form thiamine pyrophosphate (TPP), an essential cofactor for several key enzymes in the carbohydrate metabolism. Mammals must salvage this crucial nutrient from their diet in order to complement the deficiency of de novo synthesis. In the human pathogenic bacterium Staphylococcus aureus, two operons were identified which are involved in vitamin B1 metabolism. The first operon encodes for the thiaminase type II (TenA), 4-amino-5-hydroxymethyl-2-methylpyrimidine kinase (ThiD), 5-(2-hydroxyethyl)-4-methylthiazole kinase (ThiM) and thiamine phosphate synthase (ThiE). The second operon encodes a phosphatase, an epimerase and the thiamine pyrophosphokinase (TPK). The open reading frames of the individual operons were cloned, their corresponding proteins were recombinantly expressed and biochemically analysed. The kinetic properties of the enzymes as well as the binding of TPP to the in vitro transcribed RNA of the proposed operons suggest that the vitamin B1 homeostasis in S. aureus is strongly regulated at transcriptional as well as enzymatic levels

Distribution of Dinophysis species in the Bay of Biscay and possible transportpathways to Arcachon Bay

International audienceDinophysis is the most harmful toxic phytoplankton on the French coast in terms of its impact on local economyand public health. In Arcachon Bay, Dinophysis spp. have periodically affected shellfish industry for thelast ten years; the most important events are analysed in detail in this paper. Regular monitoring revealedthat these events originated outside Arcachon Bay in the open ocean. Data from 14 surveys and two coastalnetworks showed that Dinophysis was primarily found in the vicinity of Capbreton, 100 km south of themouth of Arcachon Bay. The Dinophysis distribution on the continental shelfwas determined during two surveysin 2005 and 2008: the highest concentrationswere located along the coast and reached 18000 cells.L−1. Analysisof available current data revealed that strong westerlies lead to northward currents of up to 19 cm.s−1. Thesemarinemeteorological conditionswere frequently observed just prior to Dinophysis events and lead us to suggestthat northward currents transport Dinophysis from the Capbreton area to Arcachon Bay

Freshwater from the Bay of Biscay shelves in 2009.

In April – November 2009, surface salinity data provide a good coverage of most of the south-east Bay of Biscay and nearby Aquitaine/Armorican shelves. By late April most of the shelf, in particular south of 46°N, is covered by a fresh surface layer amounting to a fresh water volume of 49·10 9 m 3 . At that time, a moderate amount of fresh water has spread over the Landes Plateau. By mid-June, this shelf water penetrates over the Cape Ferret Canyon north of the Landes Plateau. By mid-July, it is found west of the Landes Plateau to at least 4°W, with an estimated fresh-water content of 11 – 14·10 9 m 3 . Drifters deployed on June 17 in the Cape Ferret Canyon, or later on the shelves, con fi rm the spreading of shelf fresh-water over the deep ocean. Lagrangian tracking using altimetric products, also con fi rms the transport by a quasi-stationary circulation. Operational numerical simula- tions (PREVIMER, IBI, HYCOM) display this spread of the freshwater, but in different areas. In particular, all have some fresh water escaping westward near the coast in the Basque region, which is not observed. Later in the summer season, the fresh water spreads westward to south-westward and along the shelf break to at least 5.5°W in late September.N

Freshwater from the Bay of Biscay shelves in 2009.

In April – November 2009, surface salinity data provide a good coverage of most of the south-east Bay of Biscay and nearby Aquitaine/Armorican shelves. By late April most of the shelf, in particular south of 46°N, is covered by a fresh surface layer amounting to a fresh water volume of 49·10 9 m 3 . At that time, a moderate amount of fresh water has spread over the Landes Plateau. By mid-June, this shelf water penetrates over the Cape Ferret Canyon north of the Landes Plateau. By mid-July, it is found west of the Landes Plateau to at least 4°W, with an estimated fresh-water content of 11 – 14·10 9 m 3 . Drifters deployed on June 17 in the Cape Ferret Canyon, or later on the shelves, con fi rm the spreading of shelf fresh-water over the deep ocean. Lagrangian tracking using altimetric products, also con fi rms the transport by a quasi-stationary circulation. Operational numerical simula- tions (PREVIMER, IBI, HYCOM) display this spread of the freshwater, but in different areas. In particular, all have some fresh water escaping westward near the coast in the Basque region, which is not observed. Later in the summer season, the fresh water spreads westward to south-westward and along the shelf break to at least 5.5°W in late September.Versión del editor

Cooking with Bimby in a moment of recruitment:Exploring conventions and practice perspectives

Every two minutes, one Bimby is sold somewhere in the world. This multi-food processor (also known as Thermomix) has gained wide sales success in many southern European countries and promises to revolutionize the way people cook, learn about cooking, coordinate and plan food practices at home. In a period where debates about cooking skills are paradoxical; some voices concerned with deskilling, while others enhance the visibility of cooking education in the media, this domestic technology is heralded as a ‘magic’ gadget that turns dreadful cooks into notable ‘chefs’. This processor cannot be purchased in shops; it is being directly sold by salespersons that make a demonstration in future clients’ houses. These are usually social events where the host invites friends and family for a free meal swiftly produced by Bimby under the demonstrator’s supervision. Demonstrators can be seen as cultural intermediaries both marketing the product and conveying normative and symbolic messages about cooking, and also instructing on technology use. The event mixes economic, social and cultural elements, and offers a good illustration of the cultural economy workings operating in it. Based upon a case study of a demonstration – seen as a moment of recruitment of new cooking practitioners – the article examines issues around cooking competence informed by theories of practice (Shove and Pantzar, 2005; Shove et al., 2007) and conventions theory (Boltanski and The´venot, 2006 [1991]; The´venot, 2006). It is suggested that bringing a conventions together with a practice perspective offers up the possibility of developing a distinctly sociological account to analyse cooking competences in particular, and practices more generally