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The structure of phycobiliproteins of the cyanobacterium Acaryochloris marina was investigated in buffer solution at physiological temperatures, i.e. under the same conditions applied in spectroscopic experiments, using small angle neutron scattering. The scattering data of intact phycobiliproteins in buffer solution containing phosphate can be well described using a cylindrical shape with a length of about 225 Å and a diameter of approximately 100 Å. This finding is qualitatively consistent with earlier electron microscopy studies reporting a rod-like shape of the phycobiliproteins with a length of about 250 (M. Chen et al., FEBS Letters 583, 2009, 2535) or 300 Å (J. Marquart et al., FEBS Letters 410, 1997, 428). In contrast, phycobiliproteins dissolved in buffer lacking phosphate revealed a splitting of the rods into cylindrical subunits with a height of 28 Å only, but also a pronounced sample aggregation. Complementary small angle neutron and X-ray scattering experiments on phycocyanin suggest that the cylindrical subunits may represent either trimeric phycocyanin or trimeric allophycocyanin. Our findings are in agreement with the assumption that a phycobiliprotein rod with a total height of about 225 Å can accommodate seven trimeric phycocyanin subunits and one trimeric allophycocyanin subunit, each of which having a height of about 28 Å. The structural information obtained by small angle neutron and X-ray scattering can be used to interpret variations in the low-energy region of the 4.5 K absorption spectra of phycobiliproteins dissolved in buffer solutions containing and lacking phosphate, respectively. [ABSTRACT FROM AUTHOR]

Marginal iron (Fe) deficiency is prevalent in children worldwide, yet the behavioral and biochemical effects of chronic marginal Fe intakes during early development are not well characterized. Using a murine model, previous work in our laboratory demonstrated persistent behavioral disturbances as a consequence of marginal Fe intakes during early development. In the present study, Swiss-Webster mice fed a control Fe diet (75 microgram Fe/g diet, n = 13 litters) or marginal Fe diet (14 microgram Fe/g diet, n = 16 litters) during gestation and through postnatal day (PND) 75 were killed on PND 75 for assessment of tissue mineral concentrations, dopamine metabolism, myelin fatty acid composition, and c- and m-aconitase activities. In addition, these outcomes were assessed in a group of offspring (n = 13 litters) fed a marginal Fe diet during gestation and lactation and then fed a control diet from PND 21-75. Marginal Fe mice demonstrated significant differences in brain iron concentrations, dopamine metabolism and myelin fatty acid composition relative to control mice; however, no difference in c- or m-aconitase activity was demonstrated in the brain. The postnatal consumption of Fe-adequate diets among marginal Fe offspring did not fully reverse all of the observed biochemical disturbances. This study demonstrates that chronic marginal Fe intakes during early development can result in significant changes in brain biochemistry. The persistence of some of these biochemical changes after postnatal Fe supplementation suggests that they are an irreversible consequence of developmental Fe restriction. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the behavioral and cognitive outcomes associated with chronic marginal iron (Fe) intakes during early development. Offspring (3 males and 3 females/litter) of Swiss-Webster female mice who had been fed a control Fe diet (75 microg Fe/g diet) or marginal Fe diet (14 microg Fe/g diet) for 9 wk before mating were weaned on postnatal (PND) 21. Offspring of marginal Fe dams were fed either the marginal Fe diet (marginal group) or a control diet (replete group) from PND 21 throughout the duration of the study, whereas offspring of control dams consumed the control diet ad libitum (control group). On PND 30, 45 and 60, one male and female per litter underwent grip strength and auditory startle testing. A Morris maze was used to assess cognitive function in males starting at PND 50. Marginal Fe mice consistently demonstrated significantly lower grip strength, which was independent of differences in body weight. In addition, marginal Fe males demonstrated attenuated startle responsiveness, as well as altered performance in the Morris water maze. These differences in performance were found in association with lower brain Fe concentrations. Postnatal Fe supplementation did not reverse all of these disturbances because differences in brain Fe concentrations and maze learning persisted. This study demonstrates that chronic marginal Fe intakes during early development can result in persistent biochemical and behavioral changes in mice. [ABSTRACT FROM AUTHOR]

A new charge transfer salt based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the [Mo8O26]4− anion was synthesized and characterized by X-ray and spectral analysis. The crystals are triclinic, space group P1¯, a=12.996(3) A˚, b=13.135(3) A˚, c=20.705(5) A˚, α=72.01(2)°, β=85.94(2)°, γ=60.02(2)°, V=2896.9 A˚3, Z=1. The structure consists of alternating organic and inorganic layers. The inorganic layers are formed by [Mo8O26]4− anions and dimethyl formamide (DMF) molecules. The organic layers are built of two different types of BEDT-TTF molecules bonded by short S … S contacts. The compound is a metal with σ≈3 S cm−1 at room temperature. IR and Raman spectra of single crystals were analyzed and an assignment of the vibrational features was proposed. The temperature dependencies of transport parameters were obtained using the Drude–Lorentz model. [Copyright &y& Elsevier]

Extended spectral investigations of several new bis-linked tetrathiafulvalenes (TTFs) to [60]fullerene were performed. From UV–Vis–NIR–IR spectra, it was stated that charge distribution on the fullerene sphere and on the TTFs substituents is distinctly disturbed after the adduct formation. A particularly strong resonant effect was observed in the infrared spectra of the one of double-substituted fullerene molecules. [Copyright &y& Elsevier]