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991.
Igor W. Plesner 《Cell biochemistry and biophysics》1987,11(1):279-307
It is shown that the incomplete, uncompetitive inhibition pattern exhibited by oligomycin toward Na,K,ATPase cannot be explained
by a single-cycle enzyme model. In contrast, the experimental data are easily explained in terms of a dimeric enzyme, only
one subunit of which can bind oligomycin at a time, and that subunit is then rendered inactive. In a brief analysis of the
model thus obtained by way of numerical examples it is shown that it may show activation at small concentrations of moderator,
which disappears at higher concentrations, a property observed for the hydrolysis ofp-nitro-phenylphosphate, which is also catalyzed by Na,K,ATPase. 相似文献
992.
Mitochondria isolated from inbred and hybrid maize scutella were found to exhibil enhancd oxidative and phosphorylative activity in many cases when treated with physiological concentrations of IAA. It was found that the genotype being tested the substrate utilized, and the concentration of IAA applied had significant effects on the degree of enhancement or inhibition observed in each case. These results suggest that IAA is related in some manner to theactivity of the respiratory enzymes of the mitochondria. 相似文献
993.
The exhaustive extraction of lipids from soybean seeds in the native state, separation of polar lipids and determination of their functional groups (ester and phosphate) revealed that dry seeds may contain 36,7 mumole (+/- 4,6%) of polar lipids and 25,9 mumole (+/- 1.1%) phospholipids per gramme. 相似文献
994.
Karyagina Anna S. Gromov Alexander V. Grunina Tatyana M. Lyaschuk Alexander M. Poponova Maria S. Kleymenov Denis A. Strukova Natalia V. Generalova Maria S. Ryazanova Anna V. Galushkina Zoya M. Dobrynina Olga Yu. Bolshakova Tatyana N. Sergeeva Maria V. Romanovskaya-Romanko Ekaterina A. Krasilnikov Igor V. Subbotina Marina E. Lunin Vladimir G. 《Biochemistry. Biokhimii?a》2022,87(4):319-330
Biochemistry (Moscow) - Based on the previously developed approach, hybrid recombinant proteins containing short conformational epitopes (a.a. 144-153, 337-346, 414-425, 496-507) of the... 相似文献
995.
Lorena Selak Helena Osterholz Igor Stanković Nikola Hanžek Marija Gligora Udovič Thorsten Dittmar Sandi Orlić 《Environmental microbiology》2022,24(5):2282-2298
In lake ecosystems, changes in eukaryotic and prokaryotic microbes and the concentration and availability of dissolved organic matter (DOM) produced within or supplied to the system by allochthonous sources are components that characterize complex processes in the microbial loop. We address seasonal changes of microbial communities and DOM in the largest Croatian lake, Vrana. This shallow lake is connected to the Adriatic Sea and is impacted by agricultural activity. Microbial community and DOM structure were driven by several environmental stressors, including drought, seawater intrusion and heavy precipitation events. Bacterial composition of different lifestyles (free-living and particle-associated) differed and only a part of the particle-associated bacteria correlated with microbial eukaryotes. Oscillations of cyanobacterial relative abundance along with chlorophyll a revealed a high primary production season characterized by increased levels of autochthonous DOM that promoted bacterial processes of organic matter degradation. From our results, we infer that in coastal freshwater lakes dependent on precipitation-evaporation balance, prolonged dry season coupled with heavy irrigation impact microbial communities at different trophic levels even if salinity increases only slightly and allochthonous DOM inputs decrease. These pressures, if applied more frequently or at higher concentrations, could have the potential to overturn the trophic state of the lake. 相似文献
996.
Veselova Oksana Studneva Irina Dobrokhotov Igor Pal’keeva Marina Molokoedov Alexander Sidorova Maria Pisarenko Oleg 《International journal of peptide research and therapeutics》2022,28(3):1-11
International Journal of Peptide Research and Therapeutics - Middle East respiratory syndrome coronavirus (MERS-CoV) has caused a high mortality rate since its emergence in 2012 in the Middle East.... 相似文献
997.
Artur Gurgul Anna Miksza-Cybulska Tomasz Szmatoła Igor Jasielczuk Agata Piestrzyńska-Kajtoch Agnieszka Fornal Ewelina Semik-Gurgul Monika Bugno-Poniewierska 《Genomics》2019,111(2):186-195
Application of next generation sequencing for large scale genotyping in livestock is limited by high costs and challenging data analysis process. However, available restriction enzyme-based enrichment techniques like e.g. genotyping-by-sequencing (GBS) are promising tools allowing reduction of financial outlies by a high sample multiplexing and narrowing down the sequenced genome areas to the randomly distributed read tags. In this study, we tested the performance of standard, PstI endonuclease-adapted GBS protocol for population genetics in cattle, horse and sheep with application of different, including low-depth sequencing setups. It was found that the detected SNPs display desirable polymorphism parameters and are evenly scattered across the whole genome including gene coding regions. It was also shown that the SNPs can be successfully applied in population genetics, revealing the genetic differentiation of the studied breeds. The GBS approach represents a cost-effective alternative to existing genotyping methods which may find adoption in various research applications. 相似文献
998.
999.
Jos Alexandre F. Diniz‐Filho Kelly S. Souza Luis M. Bini Rafael Loyola Ricardo Dobrovolski Joo Fabricio M. Rodrigues S. Lima‐Ribeiro Levi C. Terribile Thiago F. Rangel Igor Bione Roniel Freitas Iberê F. Machado Tain Rocha Maria L. Lorini Mariana M. Vale Carlos A. Navas Natan M. Maciel Fabricio Villalobos Miguel A. Olalla‐Tarraga Sidney Gouveia 《Ecography》2019,42(6):1124-1141
Despite the widespread use of ecological niche models (ENMs) for predicting the responses of species to climate change, these models do not explicitly incorporate any population‐level mechanism. On the other hand, mechanistic models adding population processes (e.g. biotic interactions, dispersal and adaptive potential to abiotic conditions) are much more complex and difficult to parameterize, especially if the goal is to predict range shifts for many species simultaneously. In particular, the adaptive potential (based on genetic adaptations, phenotypic plasticity and behavioral adjustments for physiological responses) of local populations has been a less studied mechanism affecting species’ responses to climatic change so far. Here, we discuss and apply an alternative macroecological framework to evaluate the potential role of evolutionary rescue under climate change based on ENMs. We begin by reviewing eco‐evolutionary models that evaluate the maximum sustainable evolutionary rate under a scenario of environmental change, showing how they can be used to understand the impact of temperature change on a Neotropical anuran species, the Schneider's toad Rhinella diptycha. Then we show how to evaluate spatial patterns of species’ geographic range shift using such models, by estimating evolutionary rates at the trailing edge of species distribution estimated by ENMs and by recalculating the relative amount of total range loss under climate change. We show how different models can reduce the expected range loss predicted for the studied species by potential ecophysiological adaptations in some regions of the trailing edge predicted by ENMs. For general applications, we believe that parameters for large numbers of species and populations can be obtained from macroecological generalizations (e.g. allometric equations and ecogeographical rules), so our framework coupling ENMs with eco‐evolutionary models can be applied to achieve a more accurate picture of potential impacts from climate change and other threats to biodiversity. 相似文献
1000.