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Lidia B Vysotskaya Tatyana N Arkhipova Leila N Timergalina Aleksandr V Dedov Stanislav Yu Veselov Guzel R Kudoyarova 《Plant Physiology and Biochemistry》2004,42(3):251-255
Removal of four out of five roots did not lower transpiration and stomatal conductivity of wheat (Triticum durum Desf.) seedlings. Water content of mature expanded leaf lamina remained constant at control levels. The results suggest that the only remaining root was capable to supply the shoot with water. This was evidenced by an increase in hydraulic conductivity of the root system following partial root excision measured at low subatmospheric pressures induced by vacuum. In the absence of a hydrostatic gradient, water flow from reduced root system was initially not higher than from an intact system, but increased subsequently. ABA content was increased in roots 1 h after partial root excision, which might contribute to the increase in hydraulic conductivity. 相似文献
44.
We demonstrate a calculated alpha-helix peptide folding energy landscape which accurately simulates the first experimentally measured alpha-helix melting energy landscape. We examine a 21-amino acid, mainly polyalanine peptide and calculate the free energy along the Psi Ramachandran angle secondary folding coordinate. The experimental free energy landscape was determined using UV resonance Raman spectroscopy. The relative free energy values are very close as are the equilibrium peptide conformations. We find 2.3 kcal/mol activation barriers between the alpha-helix-like and PPII-like basins. We also find that the alpha-helix-like conformations are quite defective and the alpha-helix-like structure dynamically samples 310-helix and pi-bulges. 相似文献
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M G Simonian R A Petrosian I A Reshetnikova M V Gorlenko 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1989,(6):80-83
Using the differential-thermic and thermogravimetric methods has shown that the most promising way of fungus Aspergillus niger storing when its aggressive properties against polyamid aren't lost is to keep the culture on polymeric matter (polyamid) and in soil. 相似文献
47.
Zachary D. Stolp Aleksandr Stotland Samantha Diaz Brett J. Hilton Wesley Burford Roland Wolkowicz 《PloS one》2013,8(6)
The classical secretory pathway is essential for the transport of a host of proteins to the cell surface and/or extracellular matrix. While the pathway is well-established, many factors still remain to be elucidated. One of the most relevant biological processes that occur during transport involves the cleavage of pro-proteins by enzymes residing in the endoplasmic reticulum/Golgi/TransGolgi Network compartment. Teasing out the requirements involved in the classical secretory pathway and cleavage during transport would shed new light into mis-regulation leading to disease. Current methodologies fail to link transport and cleavage at the single cell level. Here, we describe a cell-based assay that relies on an engineered protein scaffold that can discriminate between transport to the cell surface, in the absence or presence of cleavage. Our novel two-tag system works in a robust and quantitative manner and distinguishes between cleaved and non-cleaved events based on cell surface expression of one or two epitope tags, respectively. Here, we have used the HIV-1 envelope as a substrate, which is cleaved during transport, as proof of principle. Importantly, this assay can be easily coupled to existing siRNA-based screens to identify novel regulators and effectors involved in transport and/or cleavage of cell surface proteins. In addition, unlike other in vivo based assays, the assay described here can also be easily adapted to drug discovery purposes. 相似文献
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Mazanko Maria S. Gorlov Ivan F. Prazdnova Evgeniya V. Makarenko Maxim S. Usatov Alexander V. Bren Anzhelika B. Chistyakov Vladimir A. Tutelyan Alexey V. Komarova Zoya B. Mosolova Natalia I. Pilipenko Denis N. Krotova Olga E. Struk Aleksandr N. Lin Angela Chikindas Michael L. 《Probiotics and antimicrobial proteins》2018,10(2):367-373
Probiotics and Antimicrobial Proteins - The study aims at elucidating the effect of bacilli probiotic preparations on the physiology of laying hens and roosters. Probiotic formulations were... 相似文献
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Gall Bernhard Ellervee Aleksandr Tars Märt Scheer Hugo Freiberg Arvi 《Photosynthesis research》1997,52(3):225-231
Absorption spectra of the D1-D2-cytochrom b559 complex at 4°C were investigated at pressures up to 300 MPa. Pressure effects were mostly reversible and independent of the detergent used (CHAPS or dodecyl--D-maltoside). Red-shifts were observed under pressure for the chlorophyll Qy- and the -carotene S0 S2 bands. The relatively small Qy-shift of approximately 0.15 cm-1/MPa is an indication for the absence of strongly coupled chlorophyll dimers within the reaction center and supports earlier reports from low-temperature measurements (Chang HC, Jankowiak R, Reddy NRS and Small GJ (1995) Chem Phys 197: 307–321). The carotene red-shift (seen in CHAPS) is much larger (0.5 – 0.6 cm-1/MPa) and within the range observed for excitonically coupled chlorophylls. However, since carotenes are more sensitive to changes of refractive index, we do not consider this evidence for excitonically coupled carotenes. Varying the pH and the detergent induced only small effects. Pigment exchange using high pressure instead of elevated temperature was not possible under the conditions tested. 相似文献