273 research outputs found
Calculations of K+, K- and phi Production in Near-Threshold Proton-Nucleus Collisions
K+, K- and \phi meson production in proton-nucleus (pA) collisions has been
calculated within a BUU transport model. It is shown that the nucleon-hyperon
strangeness transfer channel is essential. The role of three-body reactions has
been investigated within the medium. The targetmass dependence of
production is predicted to give important information on the in-medium
properties of all three mesons.Comment: Talk presented by H.W.B. at the Budapest 2004 workshop on 'Hot and
Dense Matter in Relativistic Heavy Ion Collisions', March 24-27, 2004,
Budapest, Hungar
Massilia norwichensis sp. nov., isolated from an air sample
A Gram-negative, rod-shaped and motile bacterial isolate, designated strain NS9T, isolated from
air of the Sainsbury Centre for Visual Arts in Norwich, UK, was subjected to a polyphasic
taxonomic study including phylogenetic analyses based on partial 16S rRNA, gyrB and lepA gene
sequences and phenotypic characterization. The 16S rRNA gene sequence of NS9T identified
Massilia haematophila CCUG 38318T, M. niastensis 5516S-1T (both 97.7% similarity), M.
aerilata 5516S-11T (97.4 %) and M. tieshanensis TS3T (97.4 %) as the next closest relatives. In
partial gyrB and lepA sequences, NS9T shared the highest similarities with M. haematophila
CCUG 38318T (94.5 %) and M. aerilata 5516-11T (94.3 %), respectively. These sequence data
demonstrate the affiliation of NS9T to the genus Massilia. The detection of the predominant
ubiquinone Q-8, a polar lipid profile consisting of the major compounds diphosphatidylglycerol,
phosphatidylethanolamine and phosphatidylglycerol and a polyamine pattern containing 2-
hydroxyputrescine and putrescine were in agreement with the assignment of strain NS9T to the
genus Massilia. Major fatty acids were summed feature 3 (C16 : 1v7c and/or iso-C15 : 0 2-OH),
C16 : 0, C18 : 1v7c and C10 : 0 3-OH. Dissimilarities in partial lepA and gyrB gene sequences as
well as results from DNA–DNA hybridizations demonstrate that strain NS9T is a representative of
an as-yet undescribed species of the genus Massilia that is also distinguished from its close
relatives based on physiological and biochemical traits. Hence, we describe a novel species, for
which we propose the name Massilia norwichensis sp. nov., with the type strain NS9T (5CCUG
65457T5LMG 28164T)
The abundance of endofungal bacterium Rhizobium radiobacter (syn. Agrobacterium tumefaciens) increases in its fungal host Piriformospora indica during the tripartite sebacinalean symbiosis with higher plants
Rhizobium radiobacter (syn. Agrobacterium tumefaciens, syn. "Agrobacterium fabrum") is an endofungal bacterium of the fungal mutualist Piriformospora (syn. Serendipita) indica (Basidiomycota), which together form a tripartite Sebacinalean symbiosis with a broad range of plants. R. radiobacter strain F4 (RrF4), isolated from P. indica DSM 11827, induces growth promotion and systemic resistance in cereal crops, including barley and wheat, suggesting that R. radiobacter contributes to a successful symbiosis. Here, we studied the impact of endobacteria on the morphology and the beneficial activity of P. indica during interactions with plants. Low numbers of endobacteria were detected in the axenically grown P. indica (long term lab-cultured, lcPiri) whereas mycelia colonizing the plant root contained increased numbers of bacteria. Higher numbers of endobacteria were also found in axenic cultures of P. indica that was freshly re-isolated (riPiri) from plant roots, though numbers dropped during repeated axenic re-cultivation. Prolonged treatments of P. indica cultures with various antibiotics could not completely eliminate the bacterium, though the number of detectable endobacteria decreased significantly, resulting in partial-cured P. indica (pcPiri). pcPiri showed reduced growth in axenic cultures and poor sporulation. Consistent with this, pcPiri also showed reduced plant growth promotion and reduced systemic resistance against powdery mildew infection as compared with riPiri and lcPiri. These results are consistent with the assumption that the endobacterium R. radiobacter improves P. indica's fitness and thus contributes to the success of the tripartite Sebacinalean symbiosis
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