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21.
DAVID G. GARBUZ OLGA G. ZATSEPINA ANDREY A. PRZHIBORO IRINA YUSHENOVA IRINA V. GUZHOVA MICHAEL B. EVGEN’EV 《Molecular ecology》2008,17(21):4763-4777
A population of Stratiomys japonica, a species belonging to the family Stratiomyidae (Diptera), common name ‘soldier flies’, occurs in a hot volcanic spring, which is apparently among the most inhospitable environments for animals because of chemical and thermal conditions. Larvae of this species, which naturally often experience temperatures more than 40 °C, have constitutively high concentrations of the normally inducible heat-shock protein Hsp70, but very low level of corresponding mRNA. Larvae of three other species of the same family, Stratiomys singularior, Nemotelus bipunctatus and Oxycera pardalina, are confined to different type semi-aquatic habitats with contrasting thermal regime. However, all of them shared the same pattern of Hsp70 expression. Interestingly, heat-shock treatment of S. japonica larvae activates heat-shock factor and significantly induces Hsp70 synthesis, whereas larvae of O. pardalina, a species from constant cold environment, produce significantly less Hsp70 in response to heat shock. Adults of the four species also exhibit lower, but detectable levels of Hsp70 without heat shock. Larvae of all species studied have very high tolerance to temperature stress in comparison with other Diptera species investigated, probably representing an inherent adaptive feature of all Stratiomyidae enabling successful colonization of highly variable and extreme habitats. 相似文献
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Sergey F. Vasilevsky Anastasiya I. Govdi El’vira E. Shults Makhmut M. Shakirov Irina V. Sorokina Tatyana G. Tolstikova Dmitry S. Baev Genrikh A. Tolstikov Igor V. Alabugin 《Bioorganic & medicinal chemistry》2009,17(14):5164-5169
The Sonogashira reaction can be applied for the preparation of acetylenic derivatives of betulonic acid where the triterpenoid moiety can serve as either the halo- or the acetylenic component. This reaction opened access to the first derivatives of betulonic acid containing either the arylethynyl (СС-Ar(Het) or the ethynyl (ССН) moieties. From the fundamental perspective, this work illustrates the possibility of selective Pd-catalyzed cross-coupling at terminal acetylenes in the presence of a terminal alkene. Hepatoprotective and anti-inflammatory properties of selected acetylenic derivatives of betulonic acid were investigated using the CCl4-induced hepatitis and carrageenan-induced edema models, respectively. 相似文献
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Gerasimova YV Erchenko IA Shakirov MM Godovikova TS 《Bioorganic & medicinal chemistry letters》2008,18(16):4511-4514
Human serum albumin (HSA) was shown to mediate oligoribonucleotide cleavage. Nonenzymatic glycation of HSA decreased the ribonuclease-like activity of the protein. According to (31)P NMR data, both native and glycated albumins induced hydrolysis of RNA molecule through 2',3'-cyclophosphate intermediates. A feasible mechanism of RNA hydrolysis by native albumin and its clinically relevant modification was discussed. 相似文献
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Popova TV Mal'shakova VS Alekseyev PV Kudryashova NV Shakirov MM Savinkova LL Drachkova IA Godovikova TS 《Nucleosides, nucleotides & nucleic acids》2004,23(6-7):921-925
Photoanlogues of the initiation substrates of the RNA polymerase II, N3ArNH(CH2)(n)NHpppA where N3Ar is 5-azido-2-nitrobenzoyl group (n = 2 or 4) were synthesized, allowing the preparation of photoreactive oligonucleotides in situ by RNA polymerase II for application as photolabels. Photolysis of p-nitro-substituted aromatic azide in aqueous medium was investigated. Using the azoxy-coupling reaction it was possible to determine whether a nitrene or p-nitrophenyl hydroxylamine azoxy compound is the trappable intermediate that is generated at ambient temperature in aqueous solution. 相似文献
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Sharipova MR Shakirov EV Balaban NP Gabdrakhmanova LA Shilova MA Rudenskaia GN Leshchinskaia IB 《Mikrobiologiia》2000,69(5):660-667
The activities of proteinases in the culture fluid and cellular fractions of Bacillus intermedius 3-19 grown under various conditions were studied. Thiol-dependent serine proteinase was the prevalent enzyme in the total pool of extracellular proteinases (70%); its catalytically active form was also detected in the cell membrane and, during active enzyme production, in the cell wall. Another enzyme, glutamyl endopeptidase (10% of the total pool), was detected in the cell membrane; it was also found in the cell wall and cytoplasm during active enzyme secretion into the growth medium. Production of these enzymes was maximal on medium containing inorganic phosphate and gelatin and decreased 2- to 4-fold on medium with glucose and lactate. The level of activity of extracellular enzymes correlated with that of corresponding membrane-bound proteins. The addition of CoCl2 (2 mM) into the medium caused an essential increase in extracellular glutamyl endopeptidase activity and promoted the release of the membrane-bound enzyme into the culture fluid. Proteolytic activity towards casein was also detected in the cytoplasm. The proteinases localized in the cytoplasm were shown to differ in their properties from those secreted. 相似文献
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M. R. Sharipova E. V. Shakirov N. P. Balaban L. A. Gabdrakhmanova M. A. Shilova G. N. Rudenskaya I. B. Leshchinskaya 《Microbiology》2000,69(5):552-558
The activities of proteinases in the culture fluid and cellular fractions ofBacillus intermedius 3–19 grown under various conditions were studied. Thiol-dependent serine proteinase was the prevalent enzyme in the total
pool of extracellular proteinases (70%); its catalytically active form was also detected in the cell membrane and, during
active enzyme production, in the cell wall. Another enzyme, glutamyl endopeptidase (10% of the total pool), was detected in
the cell membrane; it was also found in the cell wall and cytoplasm during active enzyme secretion into the growth medium.
The production of these enzymes was maximal on medium containing inorganic phosphate and gelatin and decreased 2-to 4-fold
on medium with glucose and lactate. The level of activity of extracellular enzymes correlated with that of corresponding membrane-bound
proteins. The addition of C0Cl2 (2 mM) into the medium caused an essential increase in extracellular glutamyl endopeptidase activity and promoted the release
of the membrane-bound enzyme into the culture fluid. Proteolytic activity towards casein was also detected in the cytoplasm.
The proteinases localized in the cytoplasm were shown to differ in their properties from those secreted. 相似文献
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L. A. Gabdrakhmanova E. V. Shakirov N. P. Balaban M. R. Sharipova G. N. Rudenskaya S. V. Kostrov T. V. Akimkina I. B. Leshchinskaya 《Microbiology》2000,69(5):546-551
A nutrient medium was elaborated for the efficient production of glutamyl endopeptidase by the recombinantBacillus subtilis strain AJ73 bearing theBacillus intermedius 3–19 glutamyl endopeptidase gene within a multicopy plasmid. Optimal concentrations of the main nutrients, peptone and inorganic
phosphate, were found using a multifactor approach. To provide for active growth and efficient glutamyl endopeptidase production,
the cultivation medium of the recombinant strain should be enriched in phosphorus, organic and inorganic nitrogen sources,
and yeast extract. Complex protein substrates, such as casein and gelatin, enhanced the biosynthesis of glutamyl endopeptidase.
At the same time, easily metabolizable carbon sources suppressed it. The production of glutamyl endopeptidase was stimulated
by the bivalent cations Ca2+, Mg2+, and Co2+. 相似文献