Angular dependence of resistivity in the superconducting state of NdFeAsO0.82_{0.82}F0.18_{0.18} single crystals

We report the results of angle dependent resistivity of NdFeAsO$_{0.82}$F$_{0.18}$ single crystals in the superconducting state. By doing the scaling of resistivity within the frame of the anisotropic Ginzburg-Landau theory, it is found that the angle dependent resistivity measured under different magnetic fields at a certain temperature can be collapsed onto one curve. As a scaling parameter, the anisotropy $\Gamma$ can be determined for different temperatures. It is found that $\Gamma(T)$ increases slowly with decreasing temperature, varying from $\Gamma \simeq$ 5.48 at T=50 K to $\Gamma \simeq$ 6.24 at T=44 K. This temperature dependence can be understood within the picture of multi-band superconductivity.Comment: 7 pages, 4 figure

Indirect DNA Readout by an H-NS Related Protein: Structure of the DNA Complex of the C-Terminal Domain of Ler

Ler, a member of the H-NS protein family, is the master regulator of the LEE pathogenicity island in virulent Escherichia coli strains. Here, we determined the structure of a complex between the DNA-binding domain of Ler (CT-Ler) and a 15-mer DNA duplex. CT-Ler recognizes a preexisting structural pattern in the DNA minor groove formed by two consecutive regions which are narrower and wider, respectively, compared with standard B-DNA. The compressed region, associated with an AT-tract, is sensed by the side chain of Arg90, whose mutation abolishes the capacity of Ler to bind DNA. The expanded groove allows the approach of the loop in which Arg90 is located. This is the first report of an experimental structure of a DNA complex that includes a protein belonging to the H-NS family. The indirect readout mechanism not only explains the capacity of H-NS and other H-NS family members to modulate the expression of a large number of genes but also the origin of the specificity displayed by Ler. Our results point to a general mechanism by which horizontally acquired genes may be specifically recognized by members of the H-NS family

Structural bases for the interaction of frataxin with the central components of iron–sulphur cluster assembly

Reduced levels of frataxin, an essential protein of as yet unknown function, are responsible for causing the neurodegenerative pathology Friedreich's ataxia. Independent reports have linked frataxin to iron–sulphur cluster assembly through interactions with the two central components of this machinery: desulphurase Nfs1/IscS and the scaffold protein Isu/IscU. In this study, we use a combination of biophysical methods to define the structural bases of the interaction of CyaY (the bacterial orthologue of frataxin) with the IscS/IscU complex. We show that CyaY binds IscS as a monomer in a pocket between the active site and the IscS dimer interface. Recognition does not require iron and occurs through electrostatic interactions of complementary charged residues. Mutations at the complex interface affect the rates of enzymatic cluster formation. CyaY binding strengthens the affinity of the IscS/IscU complex. Our data suggest a new paradigm for understanding the role of frataxin as a regulator of IscS functions

Increasing Functionality of apple products

Apples are an inherently 'functional', or healthy, fruit — as indicated by the age-old saying 'an apple a day keeps the doctor away'. Presumably this is at least in part because of the content of pectin (a dietary fibre that also reduces cholesterol), antioxidants, minerals, vitamins and other bioactives in apples. So why go any further? The era of functional foods is upon us and consumers are becoming more aware of such foods. Food producers and processors are also facing tighter profit margins and added value is imperative. So, functional apple products may afford new opportunities for both producers and processors. This is why they are one of the research and development (R&D) topics at Ashtown Food Research Centre (AFRC) in Dublin, as part of the EU ISAFRUIT project (a European integrated research project). The R&D at AFRC involves two streams: (i) adding bioactives (food components or dietary supplements, other than those needed to meet basic nutritional needs) to fresh-cut fruit salads with emphasis on apples; and (ii) adding bioactives/functional ingredients to processed apple products. The work will be extended to other tree fruits later in the project.The European CommissionDeposited by bulk impor

Contributions to the first European Food Conference, 2008

First European Food Congress, Ljubljana, Slovenia, 4-9 November 2008Includes abstracts for the following papers: Performance of Different Apple Cultivars in Fresh-Cut Fruit Salad Applications. Ready-Desserts from Apples: selecting/Optimising Cultivars and Processes. Physicochemical and Sensory Properties of Minimally Processed Apple Desserts Containing Creams or Custard. Effect of Dip Concentration and Time on the Efficacy of Natureseal AS1 Browning Inhibitor in Apple Wedges and on AS1 Residues in the ProductDeposited by bulk impor