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Saturnius papernai Overstreet, 1977 is recorded from the stomach of Mugil cephalus L. (Osteichthyes, Mugilidae) in the Black Sea (a new geographical record) off the southern part of the Bulgarian coast. The species is redescribed and figured on the basis of the Black Sea specimens. Some amendments to the generic diagnosis are proposed concerning the presence of a uterine seminal receptacle and a posterior (third) circular flange. It is proposed that the occurrence of S. papernai is a feature of one of the three shoals of M. cephalus in the Black Sea, i.e. the Balkan shoal. In a zoogeographical analysis, S. papernai is regarded as a Mediterranean immigrant, probably a characteristic element of only the South-Western Faunistic Region of the Black Sea. A review of the genus Saturnius Manter, 1969 is presented. 相似文献
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Anton Golovnin Larisa Melnikova Igor Shapovalov Margarita Kostyuchenko Pavel Georgiev 《PloS one》2015,10(10)
Recent data suggest that insulators organize chromatin architecture in the nucleus. The best studied Drosophila insulator proteins, dCTCF (a homolog of the vertebrate insulator protein CTCF) and Su(Hw), are DNA-binding zinc finger proteins. Different isoforms of the BTB-containing protein Mod(mdg4) interact with Su(Hw) and dCTCF. The CP190 protein is a cofactor for the dCTCF and Su(Hw) insulators. CP190 is required for the functional activity of insulator proteins and is involved in the aggregation of the insulator proteins into specific structures named nuclear speckles. Here, we have shown that the nuclear distribution of CP190 is dependent on the level of EAST protein, an essential component of the interchromatin compartment. EAST interacts with CP190 and Mod(mdg4)-67.2 proteins in vitro and in vivo. Over-expression of EAST in S2 cells leads to an extrusion of the CP190 from the insulator bodies containing Su(Hw), Mod(mdg4)-67.2, and dCTCF. In consistent with the role of the insulator bodies in assembly of protein complexes, EAST over-expression led to a striking decrease of the CP190 binding with the dCTCF and Su(Hw) dependent insulators and promoters. These results suggest that EAST is involved in the regulation of CP190 nuclear localization. 相似文献
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Tomasz Borowski Valentin Georgiev Per E. M. Siegbahn 《Journal of molecular modeling》2010,16(11):1673-1677
Catalytic cycle intermediates of a representative extradiol dioxygenase, homoprotocatechuate 2,3-dioxygenase (HPCD), have
recently been characterized in crystallo by Kovaleva and Lipscomb. The structures of the identified species indicate that
the process of inserting oxygen into the catechol ring occurs stepwise, and involves an Fe(II)-alkylperoxo intermediate and
its O–O cleavage product: a gem diol species. In general, these findings corroborate the results of our previous computational
studies; however, the fact that the gem diol species is stable enough to be observed in the crystal form seems to be at odds
with the computational mechanistic data, which suggest that this intermediate should very readily and spontaneously convert
to the epoxide species. The key question then becomes what is actually observed in the X-ray experiments. Here we report additional
computational studies undertaken with the hope of clarifying this issue. The results obtained for active site models hosting
both the native and the alternative (4-sulfonylcatechol) substrate indicate that the stability of the gem diol species is
substantially increased if an electron and a proton are added. If this occurs somehow, the lifetime of the intermediate should
be sufficient to observe it. 相似文献
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Milen Georgiev Vasil Georgiev Plamen Penchev Daniela Antonova Atanas Pavlov Mladenka Ilieva Simeon Popov 《Engineering in Life Science》2010,10(2):148-157
Cell suspension cultures of Lavandula vera (Lamiaceae), Nicotiana tabacum (Solanaceae), and Helianthus annuus (Asteraceae) were cultivated in three different ways: in shake flasks both as free suspensions and in two‐phase systems (in the presence of Amberlite XAD‐4 resin as a second phase), as well as in 3‐L stirred tank reactor, and their volatile metabolic profiles were studied using GC‐MS. A number of compounds, some of them having allelochemical and biological activities, were identified in all the three cell suspension cultures under study. Also the presence of some compounds, unusual for the intact plants, was observed. It was found that the cultivation mode strongly influences the production and the transport (secretion into the culture medium) of the low‐molecular‐mass volatile metabolites. Principal component analyses of 12 common hydrocarbons showed discrimination between the different cultivation modes (shake flasks and two‐phase systems cultivation) by first principal component (PC1) and second principal component (PC2). 相似文献