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941.
942.
943.
Nitrite binding to metmyoglobin and methemoglobin in comparison to nitric oxide binding 总被引:1,自引:0,他引:1
Alicja Wanat Joanna Gdula-Argasińska Dorota Rutkowska-Żbik Małgorzata Witko Grażyna Stochel Rudi van Eldik 《Journal of biological inorganic chemistry》2002,7(1-2):165-176
Nitrite binds reversibly to the ferriheme proteins metmyoglobin and methemoglobin in aqueous buffer solution at a physiological pH of 7.4. The spectral changes recorded for the formation of metMb(NO2-) differ significantly from those observed for the nitrosylation of metMb, which can be accounted for in terms of the different reaction products. Nitric oxide binding to metMb produces a nitrosyl product with Fe(II)-NO+ character, whereas the reaction with nitrite produces an Fe(III)-NO2- complex. The kinetics of the binding and release of nitrite by metMb and metHb were investigated by stopped-flow techniques at ambient and high pressure. The kinetic traces recorded for the reaction of nitrite with metMb exhibit excellent single-exponential fits, whereas nitrite binding to metHb is characterized by double-exponential kinetics which were assigned to the reactions of the alpha- and beta-chains of metHb with NO2-. The rate constants for the binding of nitrite to metMb and metHb were found to be much smaller than those reported for the binding of NO, such that nitrite impurities will not affect the latter reaction. The activation parameters (deltaH++,deltaS(ne),deltaV++) obtained from the temperature and pressure dependence of the reactions support the operation of a dissociative mechanism for the binding and release of nitrite, similar to that found for the binding and release of NO in metMb. 相似文献
944.
Małgorzata Karbarz Mirosław Tyrka Anna Woźniak-Strzembicka Grzegorz Czajowski Agnieszka Wardyńska Dorota Tyrka Mirosław Pojmaj Maria Wędzony 《The Annals of applied biology》2020,177(2):223-231
Powdery mildew (PM) is a common disease caused by Blumeria graminis, which affects cereals and has recently adapted to triticale. Adult-plant resistance (APR) genes provide durable protection of crops from the disease. Quantitative trait loci corresponding to the APR effects were mapped in an F2 population of “Lamberto” (susceptible) × “Moderto” (resistant). A genetic map of winter triticale was constructed based on the segregation of 863 DArT, 38 microsatellite and 10 resistance gene analogue markers. Composite interval mapping (CIM) was applied to identify three QTLs for maximum disease severity (MDS) and two for the area under disease progress curve (AUDPC) conferring resistance to the powdery mildew on chromosomes: 6A, 7A, 1B and 4R. The 39% variation in AUDPC was explained by the main QTL localised on chromosome 4R. Genes coding TRIUR3 proteins, serine/threonine protein kinase and cell wall associated kinases were localised in silico within the QTL and alternative DNA markers were proposed for flexible use in laboratories of diversified throughput. 相似文献
945.
Magdalena Kaliszewska Jakub Kruszewski Biruta Kierdaszuk Anna Kostera-Pruszczyk Monika Nojszewska Anna Łusakowska Joel Vizueta Dorota Sabat Dorota Lutyk Michał Lower Dorota Piekutowska-Abramczuk Aneta Kaniak-Golik Ewa Pronicka Anna Kamińska Ewa Bartnik Paweł Golik Katarzyna Tońska 《Human genetics》2015,134(9):951-966
946.
Discrete population models which assume unequal resource partitioning among population members bring about population stability. These models also assume that individual resource share is independent of population density. The model presented here is an attempt to answer the question What does bring about population stability—the inequality of resource partitioning itself or the independence of resource share of population density? By developing a theoretical model with varying dependence of the resource share on the population size, it is shown that the inequality itself is not sufficient for population stability; rather it is the independence of the resource share from population size which brings about this property. 相似文献
947.
Andrzej S. Skwarecki Marta Schielmann Dorota Martynow Marcin Kawczyński Aleksandra Wiśniewska Maria J. Milewska Sławomir Milewski 《Journal of peptide science》2018,24(1)
The antifungal activity of 5‐hydroxy‐4‐oxo‐l ‐norvaline (HONV), exhibited under conditions mimicking human serum, may be improved upon incorporation of this amino acid into a dipeptide structure. Several HONV‐containing dipeptides inhibited growth of human pathogenic yeasts of the Candida genus in the RPMI‐1640 medium, with minimal inhibitory concentration values in the 32 to 64 μg mL?1 range. This activity was not affected by multidrug resistance that is caused by overexpression of genes encoding drug efflux proteins. The mechanism of antifungal action of HONV dipeptides involved uptake by the oligopeptide transport system, subsequent intracellular cleavage by cytosolic peptidases, and inhibition of homoserine dehydrogenase by the released HONV. The relative transport rates determined the anticandidal activity of HONV dipeptides. 相似文献
948.
Dorota Wyczechowska Katarzyna Ruckemann John A. Duley Anne H. Simmonds Krystyna Fabianowska-majewska 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):831-834
Abstract The effect of 2-chloro-2′-deoxyadenosine and 9-β-D-arabinosyl-2-fluoroadenine on DNA methyltransferase activity in stimulated human T-lymphocytes was estimated. In comparative studies 5-aza-deoxycytidine and deoxyadenosine plus deoxycoformycin were used. These antileukemic compounds demonstrated different effects; both 2CdA and dAdo plus dCF, like 5-aza-dCyt, inhibited the enzyme activity by 85–90% after 72 hours activation of lymphocytes, while the effect of F-ara-A, under the same conditions, was insignificant. 相似文献
949.
950.