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101.
A virus recovered by inoculation of sap from Austrian vines with yellow mosaic symptoms was compared with, and found virtually indistinguishable from, an authentic Hungarian isolate of grapevine chrome mosaic nepovirus. This seems to be the first record of the virus in Austria.  相似文献   
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The percentage of species with high evolutionary distinctiveness (ED) scores in four different classes was related to conservation concern. We considered the number of species belonging to the upper level of the distribution of ED scores, and the overall distribution of ED scores in each category of concern assigned by IUCN. Generalized linear and mixed models were used to explore the relationship between variables, separately for each animal class. Overall values of ED score were higher for Squamates, Rhynchocephalia and amphibians than mammals and birds. However, the frequency distribution of ED scores was similar among classes, with a leptokurtotic distribution. Amphibians, reptiles, birds and mammals showed a markedly right skewed distribution, with a similar proportion of species in each equal category of the distribution. In all classes, the number of species with the highest ED score (positioned in the upper 20% of the frequency distribution of the variable) was very small ranging between 0.01 and 0.05%. ED score was slightly but negatively correlated with IUCN conservation status in amphibians, but unrelated in the other three classes. The bird population trend was unrelated to ED score of bird species in both USA and Europe. Also, the population’s trend for selected mammal species was unrelated to the ED score of those species. Our results provide more evidence that distribution shape of ED of animal forms is uniform among classes, with only very few species characterized by highest ED scores in each group. Surprisingly, ED score and IUCN conservation status were unrelated in the four classes examined. Finally, our study underlines that declining animals are not necessarily the most evolutionarily distinct species.  相似文献   
104.
In a context of growing resistance to classical antifungal therapy, the design of new drugs targeting alternative pathways is highly expected. Benzofuro[3,2-d]pyrimidine derivatives, derived from (?)-cercosporamide, were synthesized and evaluated as potential Candida albicans PKC inhibitors in the aim of restoring susceptibility to azole treatment. Co-administration assay of benzofuropyrimidinedione 23 and fluconazole highlighted a synergistic effect on inhibition of cell growth of a Candida albicans resistant strain.  相似文献   
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Radioactivity may have both phenotypic and genetic effects through its disruption of physiological processes and mutations. I studied the size and asymmetry of secondary sexual and ordinary morphological characters of stag beetles ( Lucanus cervus ) in two areas in the Ukraine: near Chernobyl, where levels of radiation are high, and in a control area with low background radiation. Developmental instability of morphological characters was estimated from the degree of fluctuating asymmetry using the restricted maximum likelihood parameter estimation (REML) method to partition measurement error from asymmetry. The degree of asymmetry estimated from unsigned differences in size of right and left secondary sexual character was similar to estimates based on the REML method. Beetles from the contaminated area had a significantly elevated level of fluctuating asymmetry in the secondary sexual character compared with animals from the control area. Male stag beetles found with a female had significantly lower asymmetry than males found alone. While mated males did not differ in asymmetry between areas, unmated males from Chernobyl were much more asymmetric than unmated males from the control area. These findings provide evidence for radiation disrupting developmental homeostasis, and thereby affecting the mating status of free-living beetles.  相似文献   
108.
Zusammenfassung Die Biosynthese der Makrotetrolide Monactin, Dinactin und Trinactin wurde in Kulturen von Streptomyces griseoflavus untersucht. Markierungsversuche mit radioaktivem Acetat, Propionat und l-Methionin sowie Abbau der Antibiotica und homologen Untereinheiten zeigen, daß die Kohlenstoffatome 8–10 der Homononactinsäure einer Propionateinheit entstammen, die wahrscheinlich als Startereinheit fungiert.
Metabolic products of microorganisms109. Biosynthesis of macrotetrolides. II. Biosynthesis of homononactinic acid
Summary The biosynthesis of the macrotetrolides monactin, dinactin, and trinactin, which differ from nonactin by substitution of one to three homononactinic acid units for nonactinic acid, was studied in cultures of Streptomyces griseoflavus.Labelling experiments with radioactive acetate, propionate, and l-methionine, and degradation of the antibiotics and homologous subunits, showed that the carbon atoms 8 to 10 arise from a propionate residue which probably acts as the starter unit of the carbon chain.


108. Mitt.: M. Brufani, S. Cerini, W. Fedeli, F. Mazza u. R. Muntwyler: Kristallstrukturanalyse des Chlorothricolid-methylesters. Im Druck.

Zur Biosynthese der Makrotetrolide. I. Die Grundbausteine des Nonactins. H. Pape, 1972.  相似文献   
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The Fur apoprotein has been purified and reconstituted with Co2+ and Mn2+ ions. These samples have been analyzed by UV-visible, EPR, and 1H NMR spectroscopies, by XAS, and by magnetization measurements. The apo-Fur protein is able to bind one metal dication (Co2+ or Mn2+) per monomer. A saturation magnetization study confirms the presence of a high-spin metal dication [Mn(II) S = 5/2 and Co(II) S = 3/2]. The two metal ions per Fur dimer are not in magnetic interaction (|J| < 0.1 cm-1 ). The UV-visible spectrum of the cobalt-substituted form (Co-Fur) presents two main bands at 660 nm and 540(br) nm with epsilon540 nm = 65 M-1 cm-1. The EPR spectrum gives the following g values: gx = 5.0(5), gy = 4.0(2), and gz = 2. 3(1), which are in accordance with a nearly axial (E/D < 0.11) site. The value of 55 cm-1 for the splitting (Delta) between the ground and the first excited state has been derived from an EPR saturation study and is in agreement with magnetization data. The EXAFS data of Co-Fur indicate a metal environment comprising five nitrogen/oxygen atoms at 2.11 A, the absence of sulfur, and the presence of histidines as ligands. 1H NMR of Co-Fur in H2O and D2O shows at least two exchangeable signals coming from histidine NH protons and shows the signature of carboxylate group(s). The combined spectroscopic data allow us to propose that the main metal site of Fur in Co-Fur contains at least two histidines, at least one aspartate or glutamate, and no cysteine as ligands and is in an axially distorted octahedral environment.  相似文献   
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