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51.
E. V. Putlyaev A. A. Smirnov E. A. Lazareva G. V. Klink O. V. Karpova J. G. Atabekov 《Moscow University Biological Sciences Bulletin》2013,68(4):169-173
Previously, we obtained a new viral vector based on the Alternanthera mosaic virus strain MU (AltMV-MU). The gene of interest was placed under control of two subgenomic promoters (sgp). Viral vector provided the superexpression of target proteins in Nicotiana benthamiana. In the present work, to increase the level of protein expression, this viral vector was modified and the coat protein gene was placed under control of three sgp. The new viral vector provided superexpression of the protein of interest in plants, and its amount was more than 50% of the total soluble protein in cells. The efficiency of the target protein expression in the plants transformed with viral vectors containing two and three sgp was compared. 相似文献
52.
Pierre Le Maréchal Paulette Decottignies Christophe H. Marchand Jeril Degrouard Danièle Jaillard Thierry Dulermo Marine Froissard Aleksey Smirnov Violaine Chapuis Marie-Joelle Virolle 《Applied and environmental microbiology》2013,79(19):5907-5917
Streptomyces lividans TK24 is a strain that naturally produces antibiotics at low levels, but dramatic overproduction of antibiotics occurs upon interruption of the ppk gene. However, the role of the Ppk enzyme in relation to the regulation of antibiotic biosynthesis remains poorly understood. In order to gain a better understanding of the phenotype of the ppk mutant, the proteomes of the wild-type (wt) and ppk mutant strains, grown for 96 h on R2YE medium limited in phosphate, were analyzed. Intracellular proteins were separated on two-dimensional (2D) gels, spots were quantified, and those showing a 3-fold variation or more were identified by mass spectrometry. The expression of 12 proteins increased and that of 29 decreased in the ppk mutant strain. Our results suggested that storage lipid degradation rather than hexose catabolism was taking place in the mutant. In order to validate this hypothesis, the triacylglycerol contents of the wt and ppk mutant strains of S. lividans as well as that of Streptomyces coelicolor M145, a strain that produces antibiotics at high levels and is closely related to S. lividans, were assessed using electron microscopy and thin-layer chromatography. These studies highlighted the large difference in triacylglycerol contents of the three strains and confirmed the hypothetical link between storage lipid metabolism and antibiotic biosynthesis in Streptomyces. 相似文献
53.
54.
Makoto Hibi Takashi Kawashima Pavel M. Sokolov Sergey V. Smirnov Tomohiro Kodera Masakazu Sugiyama Sakayu Shimizu Kenzo Yokozeki Jun Ogawa 《Applied microbiology and biotechnology》2013,97(6):2467-2472
l-Leucine 5-hydroxylase (LdoA) previously found in Nostoc punctiforme PCC 73102 is a novel type of Fe(II)/α-ketoglutarate-dependent dioxygenase. LdoA catalyzed regio- and stereoselective hydroxylation of l-leucine and l-norleucine into (2S,4S)-5-hydroxyleucine and (2S)-5-hydroxynorleucine, respectively. Moreover, LdoA catalyzed sulfoxidation of l-methionine and l-ethionine in the same manner as previously described l-isoleucine 4-hydroxylase. Therefore LdoA should be a promising biocatalyst for effective production of industrially useful amino acids. 相似文献
55.
The interactions between E- and Z-isomers of 3-O-methoxyimino-pregn-4-ene-20-one and its 17α-hydroxy derivative and transcortin from human blood were investigated. The substitution of the progesterone 3-oxo group for a 3-O-methoxyimino group was shown to diminish the affinity of the steroid for transcortin by approximately one order of magnitude irrespective of the substituent’s orientation. The data suggests that progesterone derivatives substituted thereby must have higher bioavailability compared to progesterone and must not significantly affect the biodynamics of glucocorticoid in vivo. 相似文献
56.
E. V. Borvinskaya I. V. Sukhovskaya A. A. Kochneva O. B. Vasilyeva M. A. Nazarova L. P. Smirnov N. N. Nemova 《Contemporary Problems of Ecology》2016,9(2):195-202
The base levels and seasonal variability of ethoxyresorufin-O-deethylase (EROD) activity, glutathione-S-transferase (GST) activity, reduced glutathione concentration (GSH) and phospholipids concentration (PhL) of Coregonus lavaretus (Linnaeus, 1758) and Coregonus muksun (Pallas, 1814) were investigated. The relationships between this biochemical markers, hepatosomatic index and seasonal growth were also examined. 相似文献
57.
E. M. Vetchinkina V. V. Komakhina D. A. Vysotskii D. V. Zaitsev A. N. Smirnov A. V. Babakov R. A. Komakhin 《Russian Journal of Genetics》2016,52(9):939-951
The chickweed (Stellaria media L.) pro-SmAMP2 gene encodes the hevein-like peptides that have in vitro antimicrobial activity against certain harmful microorganisms. These peptides play an important role in protecting the chickweed plants from infection, and the pro-SmAMP2 gene was previously used to protect transgenic tobacco and Arabidopsis plants from phytopathogens. In this study, the pro-SmAMP2 gene under control of viral CaMV35S promoter or under control of its own pro-SmAMP2 promoter was transformed into cultivated potato plants of two cultivars, differing in the resistance to Alternaria: Yubiley Zhukova (resistant) and Skoroplodny (susceptible). With the help of quantitative real-time PCR, it was demonstrated that transgenic potato plants expressed the pro-SmAMP2 gene under control of both promoters at the level comparable to or exceeding the level of the potato actin gene. Assessment of the immune status of the transformants demonstrated that expression of antimicrobial peptide pro-SmAMP2 gene was able to increase the resistance to a complex of Alternaria sp. and Fusarium sp. phytopathogens only in potato plants of the Yubiley Zhukova cultivar. The possible role of the pro-SmAMP2 products in protecting potatoes from Alternaria sp. and Fusarium sp. is discussed. 相似文献
58.
A. G. Pogorelov A. A. Smirnov V. N. Pogorelova 《Russian Journal of Developmental Biology》2016,47(2):99-102
The given paper summarizes the data on the early mammalian embryo development in culture media containing low oxygen concentration. Experimental results on in vitro modeling the hypoxia for preimplantation development are reviewed. Hypoxic conditions were shown to be available in the female reproductive tract of different mammalian species. The estimation of the embryo developing in vitro exhibits that lower oxygen level in culture media improves embryonic quality. 相似文献
59.
Smirnov V. P. Samokhin A. A. Gavrikov A. V. Kuzmichev S. D. Usmanov R. A. Vorona N. A. 《Plasma Physics Reports》2019,45(5):454-458
Plasma Physics Reports - A new concept of plasma separation of spent nuclear fuel components in a variable-cross-section chamber with a nonuniform magnetic field is proposed. Numerical simulation... 相似文献
60.
Makarov I. O. Klyuev D. A. Smirnov V. F. Smirnova O. N. Anikina N. A. Dikareva N. V. 《Microbiology》2019,88(1):72-78
Microbiology - Effect of low-frequency pulsed magnetic field and of low-intensity laser radiation on mycelial fungi actively degrading various polymer materials was studied. These factors had a... 相似文献