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141.
Iveta M. Petrova Liza L. Lahaye Tania Martiá?ez Anja W. M. de Jong Martijn J. Malessy Joost Verhaagen Jasprina N. Noordermeer Lee G. Fradkin 《Molecular and cellular biology》2013,33(20):4116-4127
Ryk pseudokinase receptors act as important transducers of Wnt signals, particularly in the nervous system. Little is known, however, of their interactions at the cell surface. Here, we show that a Drosophila Ryk family member, DERAILED (DRL), forms cell surface homodimers and can also heterodimerize with the two other fly Ryks, DERAILED-2 and DOUGHNUT ON 2. DERAILED homodimerization levels increase significantly in the presence of its ligand, WNT5. In addition, DERAILED displays ligand-independent dimerization mediated by a motif in its transmembrane domain. Increased dimerization of DRL upon WNT5 binding or upon the replacement of DERAILED''s extracellular domain with the immunoglobulin Fc domain results in an increased recruitment of the Src family kinase SRC64B, a previously identified downstream pathway effector. Formation of the SRC64B/DERAILED complex requires SRC64B''s SH2 domain and DERAILED''s PDZ-binding motif. Mutations in DERAILED''s inactive tyrosine kinase-homologous domain also disrupt the formation of DERAILED/SRC64B complexes, indicating that its conformation is likely important in facilitating its interaction with SRC64B. Finally, we show that DERAILED''s function during embryonic axon guidance requires its Wnt-binding domain, a putative juxtamembrane extracellular tetrabasic cleavage site, and the PDZ-binding domain, indicating that DERAILED''s activation involves a complex set of events including both dimerization and proteolytic processing. 相似文献
142.
Y. Y. Toporkova E. K. Bessolitsyna E. O. Smirnova S. S. Gorina O. E. Petrova L. S. Mukhtarova A. N. Grechkin 《Doklady. Biochemistry and biophysics》2018,480(1):139-142
Data on the influence of the double bond geometry on the antimicrobial properties of different isomers of etherolenic acid against phytopathogenic bacteria are presented. (ω5Z)-Etherolenic acid possesses bactericidal properties against Xanthomonas campestris ssp. vesicatoria, Pseudomonas syringae ssp. tomato, Pectobacterium atrosepticum SCRI1043; the etherolenic and (11Z)-etherolenic acids possess only bacteriostatic properties. 相似文献
143.
Nailya R. Almyasheva Maria I. Shuktueva Daria A. Petrova Dmitry S. Kopitsyn Mikhail S. Kotelev Vladimir A. Vinokurov Andrei A. Novikov 《Mycoscience》2018,59(2):147-152
Methanolysis of sunflower oil catalyzed by immobilized Aspergillus niger mycelium was studied in a packed-bed reactor. The optimal cultivation parameters for A. niger were determined using full factorial and steepest ascent experimental designs. Sunflower oil, yeast extract and soybean meal were selected as the best carbon and nitrogen sources and were used in the subsequent experiments. Intracellular lipase activity and cell mass concentration were respectively 3.2 and 2.4 times greater and cultivation period decreased by 24 h compared with the initial medium. The optimum values of these most significant parameters were as follows: sunflower oil (13.2 g/L), yeast extract (6.2 g/L), soybean meal (7.4 g/L) and incubation period (72 h) at 30 °C. With A. niger biocatalyst grown in optimized conditions, the biodiesel fuel yield reached 23.1% after sixth pass of recycled reaction mixture through the reactor. 相似文献
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147.
Effect of artificial redox mediators on the photoinduced oxygen reduction by photosystem I complexes
Anastasia Petrova Mahir Mamedov Boris Ivanov Alexey Semenov Marina Kozuleva 《Photosynthesis research》2018,137(3):421-429
The peculiarities of interaction of cyanobacterial photosystem I with redox mediators 2,6-dichlorophenolindophenol (DCPIP) and N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) were investigated. The higher donor efficiency of the reduced DCPIP form was demonstrated. The oxidized form of DCPIP was shown to be an efficient electron acceptor for terminal iron–sulfur cluster of photosystem I. Likewise methyl viologen, after one-electron reduction, DCPIP transfers an electron to the molecular oxygen. These results were discussed in terms of influence of these interactions on photosystem I reactions with the molecular oxygen and natural electron acceptors. 相似文献
148.
E. F. Khusnutdinova G. N. Apryshko A. V. Petrova O. S. Kukovinets O. B. Kazakova 《Russian Journal of Bioorganic Chemistry》2018,44(1):123-127
New propargylamines were synthesized in 72–75% yields by the interaction of 19-alkynylbetulin and 28-O-propargyl glycinamide of oleanolic acid with N-methylpiperazine under the Mannich reaction conditions. 19-[1-Methyl-4-prop-2-yn-1-yl-piperazine]-20,29,30-trinorbetulin was shown to manifest anticancer activity against one line of leukemia cells and two lines of colon cancer cells, whereas the growth of leukemia cells SR in the presence of 4-(4-methylpiperazin-1-yl)but-2-yn-1-yl-N-(3-hydroxy-28-oxoolean-12-en-28-yl)glycinate was 8%. 相似文献
149.
Pathogen‐induced conditioning of the primary xylem vessels – a prerequisite for the formation of bacterial emboli by Pectobacterium atrosepticum 下载免费PDF全文
V. Y. Gorshkov A. G. Daminova P. V. Mikshina O. E. Petrova M. V. Ageeva V. V. Salnikov T. A. Gorshkova Y. V. Gogolev 《Plant biology (Stuttgart, Germany)》2016,18(4):609-617
Representatives of Pectobacterium genus are some of the most harmful phytopathogens in the world. In the present study, we have elucidated novel aspects of plant–Pectobacterium atrosepticum interactions. This bacterium was recently demonstrated to form specific ‘multicellular’ structures – bacterial emboli in the xylem vessels of infected plants. In our work, we showed that the process of formation of these structures includes the pathogen‐induced reactions of the plant. The colonisation of the plant by P. atrosepticum is coupled with the release of a pectic polysaccharide, rhamnogalacturonan I, into the vessel lumen from the plant cell wall. This polysaccharide gives rise to a gel that serves as a matrix for bacterial emboli. P. atrosepticum‐caused infection involves an increase of reactive oxygen species (ROS) levels in the vessels, creating the conditions for the scission of polysaccharides and modification of plant cell wall composition. Both the release of rhamnogalacturonan I and the increase in ROS precede colonisation of the vessels by bacteria and occur only in the primary xylem vessels, the same as the subsequent formation of bacterial emboli. Since the appearance of rhamnogalacturonan I and increase in ROS levels do not hamper the bacterial cells and form a basis for the assembly of bacterial emboli, these reactions may be regarded as part of the susceptible response of the plant. Bacterial emboli thus represent the products of host–pathogen integration, since the formation of these structures requires the action of both partners. 相似文献
150.
T. A. Petrova A. Yu. Lianguzov N. M. Malygina 《Journal of Evolutionary Biochemistry and Physiology》2016,52(1):37-45
A set of normal biochemical indices of the hemolymph plasma in the gastropod pulmonate mollusc Achatina fulica was described in this study. A comparative analysis of the whole plasma and its subfractions enriched with and depleted of the oxygen-carrying protein hemocyanin was carried out using spectrophotometry and spectrofluorimetry. Individual features of the absorption spectra were analyzed using fourth derivatives. An optimal method to estimate the protein concentration was identified. The buffer capacity, equivalence points and pK values of the dominant buffer groups were calculated to characterize the acid-base properties of hemolymph plasma and its subfractions. A major role in maintaining the hemolymph buffer capacity was shown to belong to the bicarbonate buffering system. The results of this study are compared with the data for Helix pomatia available in literature. In the future, the tested indices will be used to devise ecotoxicological criteria for environmental assessment. 相似文献