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61.
Abstract Several mini-replicons, derivatives of a large (107-kb) cryptic Thiobacillus versutus pTAV1 plasmid, were obtained. The pTAV1 derivatives confer all functions sufficient for autonomous replication in T. versutus but they cannot be maintained in Escherichia coli . The fragment of pTAV1 (4-kb) included in the smallest mini-replicon, pTAV202, encodes for two proteins of approximately 26 and 45 kDa. The region responsible for stable maintenance of pTAV1 derivatives (and presumably entire pTAV1) was located in defined 14-kb fragment of pTAV1 genome. Hybrid plasmids composed of E. coli vectors (pBGS18 or pWSK29) and pTAV202 replicon were constructed and their activity in both hosts tested. 相似文献
62.
Zenon Lukaszewski Ryszard Siwecki Jadwiga Opydo Wlodzimierz Zembrzuski 《Trees - Structure and Function》1993,7(3):169-174
Summary The patterns of radial distribution of copper, lead, zinc and cadmium in two species of poplar, growing under polluted conditions near a copper smelter, were investigated. Populus marilandica is very resistant to such pollution, but P. balsamifera is sensitive. Soils were examined for concentrations of these metals, and only a surface layer of soil was polluted with copper and lead. P. balsamifera absorbed much more cadmium than P. marilandica under the same conditions. P. marilandica shows a pattern of copper radial distribution with significantly increased concentration of the meral in the layers in the middle of the trunk compared to P. balsamifera. Zinc and cadmium have a pattern with increased metal concentration from the bark towards the pith of the tree. In the case of copper and lead the pattern indicates increased concentrations of these metals in the rings adjacent to the pith while the pattern in other parts of the tree remains unconfirmed due to poor precision. Poplar xylem seems to accumulate zinc and cadmium while the content of lead in xylem is much lower than in the adjacent soil.This paper is dedicated to the memory of Professor Stefan Bialobok, Institute of Dendrology, Polish Academy of Sciences in Kornik 相似文献
63.
Maria Billert Tatiana Wojciechowicz Mariami Jasaszwili Dawid Szczepankiewicz Jadwiga Waśko Sandra Kaźmierczak Mathias Z. Strowski Krzysztof W. Nowak Marek Skrzypski 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(12):1449-1457
Phoenixin-14 (PNX) is a newly discovered peptide produced by proteolytic cleavage of the small integral membrane protein 20 (Smim20). Previous studies showed that PNX is involved in controlling reproduction, pain, anxiety and memory. Furthermore, in humans, PNX positively correlates with BMI suggesting a potential role of PNX in controlling fat accumulation in obesity. Since the influence of PNX on adipose tissue formation has not been so far demonstrated, we investigated the effects of PNX on proliferation and differentiation of preadipocytes using 3T3-L1 and rat primary preadipocytes. We detected Smim20 and Gpr173 mRNA in 3T3-L1 preadipocytes as well as in rat primary preadipocytes. Furthermore, we found that PNX peptide is produced and secreted from 3T3-L1 and rat primary adipocytes. PNX increased 3T3-L1 preadipocytes proliferation and viability. PNX stimulated the expression of adipogenic genes (Pparγ, C/ebpβ and Fabp4) in 3T3-L1 adipocytes. 3T3-L1 preadipocytes differentiated in the presence of PNX had increased lipid content. Stimulation of cell proliferation and differentiation by PNX was also confirmed in rat preadipocytes. PNX failed to induce AKT phosphorylation, however, PNX increased cAMP levels in 3T3-L1 cells. Suppression of Epac signalling attenuated PNX-induced Pparγ expression without affecting cell proliferation. Our data show that PNX stimulates differentiation of 3T3-L1 and rat primary preadipocytes into mature adipocytes via cAMP/Epac-dependent pathway. In conclusion our data shows that phoenixin promotes white adipogenesis, thereby may be involved in controlling body mass regulation. 相似文献
64.
65.
Magdalena Dyduch-Siemińska Jadwiga Żebrowska Jacek Gawroński 《Plant Cell, Tissue and Organ Culture》2018,135(3):463-471
The phenomenon of morphogenesis observed in in vitro cultures, as the ability of cultured cells and/or plant tissues to regenerate into a complete plant, is used for propagation of orchard species plants of the genus Fragaria spp. Genetic mechanisms controlling the in vitro morphogenesis process are still not fully understood. Research has been conducted to broaden knowledge about the genetic control of this process. The aim of this study was to determine the effect of cytoplasmic loci on the inheritance of the cell morphogenetic potential within the species Fragaria x ananassa. The study included five strawberry cultivars—‘Dukat’, ‘Jota’, ‘Temptation’, ‘Pastel’ and ‘Senga Sengana’. The third Griffing method of diallel crossing was fully useful for achieving the purpose of the research, because it allowed, by comparing the effects of reciprocal crosses for each crossing combination, determining the possible impact of cytoplasmic loci on the inheritance of morphogenetic abilities in the analyzed cultivars. Evaluation of the effects of reciprocal crosses showed different modes of inheritance of the morphogenetic potential in vitro of plant cells of these strawberry cultivars. The strawberry cultivar ‘Dukat’ transmitted genetic determinants of the morphogenetic potential cytoplasmically. Nuclear transmission of the morphogenetic potential was recorded for the cultivar ‘Senga Sengana’. ‘Jota’, ‘Temptation’ and ‘Pastel’ cultivars passed on this trait in a cytoplasmic-nuclear mode. Morphogenesis efficiency of hybrids, whose maternal forms transmitted the morphogenetic potential in a cytoplasmic-nuclear mode, depended likely on the interaction between the maternal plasmotype and the paternal nuclear genes. 相似文献
66.
67.
Specificity of Formation of Complexes Between Coat Protein and Bacteriophage f2 RNA 总被引:2,自引:2,他引:0
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The specificity of formation of phage f2 RNA-protein complexes was studied. Complex I contains up to 8 mol of coat protein per 1 mol of RNA. Its formation proceeds equally well in medium (i) without magnesium ions, (ii) containing magnesium ions, (iii) containing 4 mM EDTA, and (iv) at temperatures from 0 to 45 C. Complex II contains up to 200 mol of coat protein per 1 mol of RNA. Its formation is inhibited by the presence of magnesium ions in medium. Formaldehyde- or methoxyamine-treated f2 RNA in which only exposed bases were modified showed a normal pattern of complex II formation, whereas formation of complex I was inhibited or abolished. We conclude that complex I formation involves the interaction between coat protein and specific region of exposed bases in RNA. A possible site of attachment of coat protein is discussed. 相似文献
68.
Jadwiga Sobocińska 《Origins of life and evolution of the biosphere》1973,4(2):307-308
Total body water (TBW) and extracellular volume (EVC) were measured simultaneously with3H and82Br in male albino rats after two, four and eight weeks of immobilization. On the basis of these measurements the intracellular fluid volume (ICV) was calculated. It was found that immobilization caused no changes in the volume and distribution of body fluids. 相似文献
69.
Agnieszka Chmielarczyk Monika Pobiega Dorota Romaniszyn Jadwiga Wójkowska-Mach 《Folia microbiologica》2018,63(2):191-196
Non-fermentative Gram-negative bacilli are now one of the most important causes of severe infections in Polish hospitals. Acinetobacter species are serious concern because of the high prevalence of multi-drug resistance among strains. Resistance profiles for 53 Gram-negative non-fermentative blood isolates were done. MLST was carried out using 44 strains representing the most commonly isolated species: A. baumannii, P. aeruginosa, and S. maltophilia. MLST revealed that all 22 A. baumannii belonged to sequence type (ST) 2. The P. aeruginosa isolates belonged to 10 different STs. Four S. maltophilia isolates matched STs present in the database (ST4, ST15, ST116, ST142), seven isolates showing novel sequence types. Among P. aeruginosa and S. maltophilia PFGE confirmed the genetical variety of strains. 相似文献
70.
Paulina Smyda-Dajmund Jadwiga Śliwka Iwona Wasilewicz-Flis Henryka Jakuczun Ewa Zimnoch-Guzowska 《Plant cell reports》2016,35(6):1345-1358