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81.
Effect of artificial redox mediators on the photoinduced oxygen reduction by photosystem I complexes
Anastasia Petrova Mahir Mamedov Boris Ivanov Alexey Semenov Marina Kozuleva 《Photosynthesis research》2018,137(3):421-429
The peculiarities of interaction of cyanobacterial photosystem I with redox mediators 2,6-dichlorophenolindophenol (DCPIP) and N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) were investigated. The higher donor efficiency of the reduced DCPIP form was demonstrated. The oxidized form of DCPIP was shown to be an efficient electron acceptor for terminal iron–sulfur cluster of photosystem I. Likewise methyl viologen, after one-electron reduction, DCPIP transfers an electron to the molecular oxygen. These results were discussed in terms of influence of these interactions on photosystem I reactions with the molecular oxygen and natural electron acceptors. 相似文献
82.
Extensive phenotypic diversification coexists with little genetic divergence and a lack of population structure in the White Wagtail subspecies complex (Motacilla alba)
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Georgy A. Semenov Evgeniy A. Koblik Yaroslav A. Red'kin Alexander V. Badyaev 《Journal of evolutionary biology》2018,31(8):1093-1108
Geographically clustered phenotypes often demonstrate consistent patterns in molecular markers, particularly mitochondrial DNA (mtDNA) traditionally used in phylogeographic studies. However, distinct evolutionary trajectories among traits and markers can lead to their discordance. First, geographic structure in phenotypic traits and nuclear molecular markers can be co‐aligned but inconsistent with mtDNA (mito‐nuclear discordance). Alternatively, phenotypic variation can have little to do with patterns in neither mtDNA nor nuclear markers. Disentangling between these distinct patterns can provide insight into the role of selection, demography and gene flow in population divergence. Here, we examined a previously reported case of strong inconsistency between geographic structure in mtDNA and plumage traits in a widespread polytypic bird species, the White Wagtail (Motacilla alba). We tested whether this pattern is due to mito‐nuclear discordance or discrepancy between morphological evolution and both nuclear and mtDNA markers. We analysed population differentiation and structure across six out of nine commonly recognized subspecies using 17 microsatellite loci and a combination of microsatellites and plumage indices in a comprehensively sampled region of a contact between two subspecies. We did not find support for the mito‐nuclear discordance hypothesis: nuclear markers indicated a subtle signal of genetic clustering only partially consistent with plumage groups, similar to previous findings that relied on mtDNA. We discuss evolutionary factors that could have shaped the intricate patterns of phenotypic diversification in the White wagtail and the role that repeated selection on plumage ‘hotspots’ and hybridization may have played. 相似文献
83.
84.
The protein-free method was applied for the investigation of histone H1 DNA complexes formation. The main advantage of this method is the possibility to get intramolecular compact structures at interaction of individual spread molecules of DNA with histone H1. It was shown that in the presence of 0.2-5 micrograms/ml of histone H1 in hypophase there are three types of structures on electronmicroscopic preparations: fibres of non-compacted DNA, compact fibres with twisted strands of duplex DNA and compacted rod-like and circular structures where separate fibres of duplex DNA could not be distinguished. The study of compact structures morphology allows to conclude that they are formed by side-by-side association of DNA fibres, as it takes place in the case of triple rings formation at the compactization of circular DNA due to trivaline binding. At increasing ionic strength there is a tendency for transition from second type structures to the third type structures. The latter can be explained by transition from non-cooperative to cooperative binding of histone H1 to DNA. 相似文献
85.
Hypoxic trainings of rats (maintenance in the test chamber at the "altitude" 4 km above the sea level for 7 hours a day for two weeks) prevent pneumonia-induced activation of peroxidation for lipids of the liver mitochondria. This increases the phosphorylating respiration rate when lipemic serum is used as an oxidation substrate (not succinate). In these experiments the efficiency of oxidative phosphorylation (delta ADP/delta O) when either succinate and glutamate or glutamate and malate have been oxidated corresponded to the values typical of intact animals and was higher when lipemic serum was used. It is supposed that rearrangement of energy reactions of mitochondria is connected with intensification of utilization of lipids and conjugation between their oxidation and phosphorylation. This rearrangement is apparently aimed to prevent the energy deficiency in the organism which arises in patients with pneumonia. 相似文献
86.
N V Semenov 《Antibiotiki》1984,29(9):666-671
A single administration of the LD50 of bruneomycin, carminomycin, rubomycin or olivomycin and the use of the antibiotics for 10 days in a dose 2 times higher than the therapeutic one and amounting to 10 per cent of the LD50 induced dystrophic and destructive changes in the sexual glands of mice. The changes in the testis were more pronounced after the single use of the antibiotics. Recovery processes were observed in the testis beginning from the middle of the third week after the use of carminomycin and rubomycin and from the end of the second week after the use of olivomycin. Bruneomycin was an exception: the pronounced destructive changes in the sexual glands after its single or repeated use persisted within the observation period. 相似文献
87.
Fifty four patients with postresection gastritis and 13 healthy adults were examined. 141 microbial cultures belonging to 33 species were isolated from the gastric juice of the patients. In the healthy persons 27 cultures belonging to 7 species were isolated from the gastric juice. In the gastric juice of the patients there predominated enteric bacteria and enterococci (64.8 +/- 6.5 and 57.4 +/- 6.7 per cent respectively). Among the enteric bacteria Escherichia coli and Proteus spp. were the most frequent. Contamination of the gastric juice by such microbes amounted to 10(5)-10(9) microbial bodies per 1 ml. The isolates were mainly sensitive to gentamicin (84.8 +/- 2.9 per cent). 相似文献
88.
M V Semenov 《Tsitologiia》1990,32(10):965-976
Sera of patients with rheumatic diseases often contain autoantibodies to nuclear antigens. Problems of the specificity of autoantibodies and of their usage for studying nuclear components and of the whole nuclear organization are reviewed. 相似文献
89.
M V Semenov 《Tsitologiia》1990,32(5):489-493
Sera of rheumatology patients with antikinetochore autoantibodies are identified. Immunoblot of human cell proteins showed that all the sera contained autoantibodies to kinetochore proteins A and B. In Chinese hamster cells proteins with m. m. 45 kD, 100 kD and 110 kD are presumably kinetochore proteins, whereas in murine cells these are proteins with m. m. 45 kD 85 kD and 100 kD. 相似文献
90.