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The Retention Index (I) value and the different I values from two columns, carbowax 20M (20M) and OV101 (ΔI:I20M ? IOV101) of aliphatic compounds were calculated by several kinds of linear equations under programmed linear temperature conditions. The equations could be used to predict appropriate compounds as well as a database of I and ΔI values.  相似文献   
64.
l-Lysine monohydrochloride and d-glucose were allowed to react in a bicarbonate buffer of pH 8.8 under refluxing. The reaction mixture was then chromatographed on a thin-layer plate of Kiesel Gel using n-propanol ethyl-acetate water 25% aqueous ammonia (6: 1: 2: 1 v/v) as a developing agent. Elson-Morgan-reactive spots on the chromatogram were eluted individually, and each of the eluates was incubated with L. bifidus var. pennsylvanicus in a defined medium. A certain fraction on the chromatogram showed remarkably promoting effect on both the acid productivity and the growth of the organism. And such effect of the fraction was much stronger than that of N-acetyl-d-glucosamine which had been known as a “Bifidus Factor”  相似文献   
65.
The amino acid composition of beef liver d-glycerate dehydrogenase (EC 1.1.1.29) was determined. Results of sodium dodecyl sulfate gel electrophoresis and measurements of the number of NADH bound by the enzyme and the number of the essential sulfhydryl groups suggested that the enzyme was composed of two identical subunits with the molecular weight of 36,000. Close relation between the essential sulfhydryl groups and the coenzyme binding site was also suggested. Effect of an alkylating agent (bromopyruvate) with the structure similar to the substrate was studied. Effects of iodoacetate and iodoacetamide were also studied. It was suggested that these reagents behaved as active-site-directed irreversible inhibitors of the enzyme. Bromopyruvate exhibited a high affinity to the enzyme. Iodoacetate (anionic reagent) had a higher affinity than iodoacetamide (neutral reagent).  相似文献   
66.
A coupled enzyme system of orotidine-5′-phosphate pyrophosphorylase and orotidine-5′-phosphate decarboxylase has been purified approximately 30-fold from cell-free extract of Micrococcus glutamicus 534 Co–147 by means of acid treatment and fractionations with ammonium sulfate and ethanol addition, and properties of the enzyme system have been studied.

Optima of pH, temperature and substrate concentrations for the activity of the purified enzyme system have been investigated, and compared with those of the same enzyme system from dried brewer’s yeast. Furthermore, effects of various inhibitors on the enzyme activity have been examined and it has become evident that the enzyme system is completely inactivated by addition of chelating agent such as EDTA, and regenerated by further addition of magnesium ion.  相似文献   
67.
The quinoline antibiotics aurachins C, D, and L, and a structurally simplified analog of aurachin C were synthesized from 1-(2-nitrophenyl)butane-1,3-dione via reductive cyclizations of δ-nitro ketone intermediates, with zinc or iron as key steps. The results of antimicrobial tests indicate that the N-hydroxyquinolone nucleus mimics the electron carrier in the respiratory chain more strongly than the quinoline N-oxide nucleus.  相似文献   
68.
In terrestrial ecosystems, plant roots are colonized by various clades of mycorrhizal and endophytic fungi. Focused on the root systems of an oak‐dominated temperate forest in Japan, we used 454 pyrosequencing to explore how phylogenetically diverse fungi constitute an ecological community of multiple ecotypes. In total, 345 operational taxonomic units (OTUs) of fungi were found from 159 terminal‐root samples from 12 plant species occurring in the forest. Due to the dominance of an oak species (Quercus serrata), diverse ectomycorrhizal clades such as Russula, Lactarius, Cortinarius, Tomentella, Amanita, Boletus, and Cenococcum were observed. Unexpectedly, the root‐associated fungal community was dominated by root‐endophytic ascomycetes in Helotiales, Chaetothyriales, and Rhytismatales. Overall, 55.3% of root samples were colonized by both the commonly observed ascomycetes and ectomycorrhizal fungi; 75.0% of the root samples of the dominant Q. serrata were so cocolonized. Overall, this study revealed that root‐associated fungal communities of oak‐dominated temperate forests were dominated not only by ectomycorrhizal fungi but also by diverse root endophytes and that potential ecological interactions between the two ecotypes may be important to understand the complex assembly processes of belowground fungal communities.  相似文献   
69.
In natural forests, hundreds of fungal species colonize plant roots. The preference or specificity for partners in these symbiotic relationships is a key to understanding how the community structures of root‐associated fungi and their host plants influence each other. In an oak‐dominated forest in Japan, we investigated the root‐associated fungal community based on a pyrosequencing analysis of the roots of 33 plant species. Of the 387 fungal taxa observed, 153 (39.5%) were identified on at least two plant species. Although many mycorrhizal and root‐endophytic fungi are shared between the plant species, the five most common plant species in the community had specificity in their association with fungal taxa. Likewise, fungi displayed remarkable variation in their association specificity for plants even within the same phylogenetic or ecological groups. For example, some fungi in the ectomycorrhizal family Russulaceae were detected almost exclusively on specific oak (Quercus) species, whereas other Russulaceae fungi were found even on “non‐ectomycorrhizal” plants (e.g., Lyonia and Ilex). Putatively endophytic ascomycetes in the orders Helotiales and Chaetothyriales also displayed variation in their association specificity and many of them were shared among plant species as major symbionts. These results suggest that the entire structure of belowground plant–fungal associations is described neither by the random sharing of hosts/symbionts nor by complete compartmentalization by mycorrhizal type. Rather, the colonization of multiple types of mycorrhizal fungi on the same plant species and the prevalence of diverse root‐endophytic fungi may be important features of belowground linkage between plant and fungal communities.  相似文献   
70.
Aquporins are intrinsic membrane proteins that function as water channel to transport water and/or mineral nutrients across biological membranes. In this study, we aimed to clarify whether water structure can be changed by the presence of ceramics and whether such a change can be determined by aquaporin. First, we confirmed that ceramics could transform tap water into active tap water by increasing water permeability through aquaporin. We also found that this change in water permeability by treatment with ceramics occurred in distilled water. The distilled water was determined to exhibit the same aquaporin permeability as the original tap water. Our data indicate that the aquaporin permeability of water can be changed by severe physical shocks, such as slapping and sonication, which is consistent with the implication that the aquaporin permeability is closely related to the structure of the water. In this study, using aquaporins, we first reported that the treatment of water with ceramics can affect the structure of water, and the water can retain the structure for a given period under certain condition  相似文献   
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