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The work was focused on the investigation of possible dependencies between the development of viral infection in plants and the presence of high heavy metal concentrations in soil. Field experiments have been conducted in order to study the development of systemic tobacco mosaic virus (TMV) infection in Lycopersicon esculentum L. cv. Miliana plants under effect of separate salts of heavy metals Cu, Zn and Pb deposited in soil. As it is shown, simultaneous effect of viral infection and heavy metals in tenfold maximum permissible concentration leads to decrease of total chlorophyll content in experiment plants mainly due to the degradation of chlorophyll a. The reduction of chlorophyll concentration under the combined influence of both stress factors was more serious comparing to the separate effect of every single factor. Plants' treatment with toxic concentrations of lead and zinc leaded to slight delay in the development of systemic TMV infection together with more than twofold increase of virus content in plants that may be an evidence of synergism between these heavy metal's and virus' effects. Contrary, copper although decreased total chlorophyll content but showed protective properties and significantly reduced amount of virus in plants.  相似文献   
3.
Wine champagnizing, a process involving the use of champagne yeasts immobilized by inclusion into cryogels of polyvinyl alcohol, has been studied. Treatment of yeast cells with the autoregulatory factor d1 was proposed as a means of preventing the cell escape from the carrier matrix. Such a treatment inhibited growth and proliferation processes in yeasts cells, without affecting the activity of fermentation; the resulting champagne had the same organoleptic and chemical characteristics as its counterparts obtained using traditional techniques.  相似文献   
4.
The precipitation of N-cetylamine, N-cetylacetamide, hexan-1,2-diol, cetyl alcohol, and poly(butyl metacrylate) in acetone-water media in the presence of the lipase from Pseudomonas fluorescens was found to be accompanied by the coprecipitation of the enzyme. Within the lyophilized coprecipitates, the lipase exhibits a high catalytic activity and enantioselectivity in the reaction of (1RS)-phenylethanol acetylation with vinyl acetate in t-butyl methyl ether. In order of increasing lipase activity, the coprecipitates can be arranged in the series: cetyl alcohol, poly(butyl metacrylate), hexadecane-1,2-diol, N-cetylamine, and N-cetylacetamide, with the activity 2.5- to 19-fold exceeding the activity of the native enzyme. The immobilization of the lipase on solid supports, such as Celite 545 (physical sorption) and Eupergit C250L (covalent binding), in the presence of hexadecane-1,2-diol was found to increase the esterifying activity of the enzyme. The English version of the paper.  相似文献   
5.
The thermotolerant, ethanol-producing yeast strain Kluyveromyces marxianus IMB3 has been immobilized in calcium alginate gel and poly(vinyl alcohol) cryogel (PVAC) beads. The immobilized preparations were used as biocatalyst in fed-batch reactor systems for prolonged periods. The substrate utilized in each case consisted of sugar cane molasses diluted to yield a sugar load of 140?g/l. During the first cycle the maximum ethanol concentration produced by the alginate system was 57?g/l, representing 80% of the maximum theoretical yield. In the system employing the PVAC-immobilized biocatalyst, ethanol production increased to a maximum of 52–53?g/l, representing 73% of the maximum theoretical yield. In both cases, maximum ethanol concentration was achieved within a 72-hour period. When each system was operated on a fed-batch basis for a prolonged period of time the average ethanol concentrations produced in the alginate- and the PVAC-immobilized systems were 21 and 45?g/l, respectively. The results suggest that the PVAC-based immobilization system may provide a more practical alternative to alginate for the production of ethanol by K. marxianus IMB3 in continuous or semi-continuous fermentation systems.  相似文献   
6.

Backgroud  

Extramedullary hematopoiesis (EMH) is defined as the presence of hematopoietic stem cells such as erythroid and myeloid lineage plus megakaryocytes in extramedullary sites like liver, spleen and lymph nodes and is usually associated with either bone marrow or hematological disorders. Mammary EMH is a rare condition either in human and veterinary medicine and can be associated with benign mixed mammary tumors, similarly to that described in this case.  相似文献   
7.
Laser-induced temperature jump experiments were used for testing the rates of thermoinduced conformational transitions of reaction center (RC) complexes in chromatophores of Chromatium minutissimum. The thermoinduced transition of the macromolecular RC complex to a state providing effective electron transport from the multiheme cytochrome c to the photoactive bacteriochlorophyll dimer within the temperature range 220–280 K accounts for tens of seconds with activation energy 0.166 eV/molecule. The rate of the thermoinduced transition in the cytochrome–RC complex was found to be three orders of magnitude slower than the rate of similar thermoinduced transition of the electron transfer reaction from the primary to secondary quinone acceptors studied in the preceding work (Chamorovsky et al. in Eur Biophys J 32:537–543, 2003). Parameters of thermoinduced activation of the electron transfer from the multiheme cytochrome c to the photoactive bacteriochlorophyll dimer are discussed in terms of cytochrome c docking onto the RC.  相似文献   
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The authors present the results of the electron microscopic and roentgenological study of the crystalline protein of diphtheria toxin. On the basis of direct measurements of the crystal image and diffraction pictures it was possible to calculate the interplane distances of the placement of molecules in the crystal. Examination in polarization microscope showed that the crystals were optically uniaxial with a direct extinction and a positive character of elongation. Molecular aggregates revealed in the protein molecules resembled the caudal part of the bacteriophage by structure.  相似文献   
10.
Zubov AV  Zubov KV  Zubov VA 《Biofizika》2007,52(4):585-592
The distribution of water clusters in fresh rain water and in rain water that was aged for 30 days (North Germany, 53 degrees 33' N, 12 degrees 47' E, 293 K, rain on 25.06.06) as well as in fresh vegetables and fruits was studied by flicker noise spectroscopy. In addition, the development of water clusters in apples and potatoes during ripening in 2006 was investigated. A different distribution of water clusters in irrigation water (river and rain) and in the biomatrix of vegetables (potatoes, onions, tomatoes, red beets) and fruits (apples, bananas) was observed. It was concluded that the cluster structure of irrigation water differs from that of water of the biomatrix of vegetables and fruits and depends on drought and the biomatrix nature. Water clusters in plants are more stable and reproducible than water clusters in natural water. The main characteristics of cluster formation in materials studied were given. The oscillation frequencies of water clusters in plants (biofield) are given at which they interact with water clusters of the Earth hydrosphere. A model of series of clusters 16(H2O)100 <--> 4(H2O)402 <--> 2(H2O)903 <--> (H2O)1889 in the biomatrix of vegetables and fruits was discussed.  相似文献   
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