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51.
52.
A novel bacterium carrying out anaerobic ammonium oxidation in a reactor for biological treatment of the filtrate of wastewater fermented sludge 总被引:1,自引:0,他引:1
S. V. Khramenkov M. N. Kozlov M. V. Kevbrina A. G. Dorofeev E. A. Kazakova V. A. Grachev B. B. Kuznetsov D. Yu. Polyakov Yu. A. Nikolaev 《Microbiology》2013,82(5):628-636
A new genus and species of bacteria capable of ammonium oxidation under anaerobic conditions in the presence of nitrite is described. The enrichment culture was obtained from the Moscow River silt by sequential cultivation in reactors with selective conditions for anaerobic ammonium oxidation. Bacterial cells were coccoid, ~0.4 × 0.7 μm, with the intracellular membrane structures typical of bacteria capable of anaerobic ammonium oxidation (anammoxosome and paryphoplasm). The cells formed aggregates 5–25 μm in diameter (10 μm on average). They were readily adhered to solid surfaces. The cells were morphologically labile: they easily lost their content and changed their morphology during fixation for electron microscopy. The organism was capable of ammonium oxidation with nitrite. The semisaturation constants Ks for nitrite and ammonium were 0.38 mg N-NO2/L and 0.41 mg N-NH4/L, respectively. The maximal nitrite concentrations for growth were 90 and 75 mg N-NO2/L for single and continuous application, respectively. The doubling time was 32 days, μmax = 0.022 day?1, the optimal temperature and pH were 20°C and 7.8–8.3, respectively. According to the results of 16S rRNA gene sequencing, the bacterium was assigned to a new genus and species within the phylum Planctomycetes. The proposed name for the new bacterium is Candidatus Anammoximicrobium moscowii gen. nov., sp. nov. (a microorganism carrying out anaerobic ammonium oxidation, isolated in the Moscow region). 相似文献
53.
A. V. Kuznetsov 《Journal of biological physics》2013,39(1):145-158
Based on published experimental evidence, this paper develops a model for the transport of a pulse of radiolabeled organelles in a unipolar Drosophila motor neuron. In particular, since published data indicate that no microtubules (MTs) travel from the primary neurite into the dendrite, it is investigated how organelles are transported into the dendrite. Analytical solutions describing concentrations of kinesin- and dynein-driven organelles in the primary neurite, axon, and dendrite are obtained. The effects of increasing the width of the pulse and increasing the rate of organelle transition rate from the kinesin-driven to the dynein-driven state are investigated. 相似文献
54.
Spores of Cystopteridaceae from northern Asia were examined using scanning electron microscopy. To evaluate the utility of spore morphology in the taxonomy of each genus, we examined spores of 14 species: seven species each of Gymnocarpium and Cystopteris. Among these are 12 species occurring in northern Asia and two species from other regions for comparative studies. The study focused particularly on perispore characters and spore size. Spores of all species examined are monolete, bean-shaped, with a range in spore size of 26–56 × 18–37 μm for Cystopteris and 25–48 × 16–34 μm for Gymnocarpium. The perispore is morphologically diverse within Cystopteris, but less so within Gymnocarpium. The perispore of the Cystopteris spores is characterised by folds and spines that are separate or form complex sculptural elements. Sacci, ridges and flanges, sometimes on the same spore, are characteristic of the perispore of Gymnocarpium. Spores have straight laesura over which the perispore forms a crest. The crest represents a high and flat fold, which is entire, foveolate or reticulate. 相似文献
55.
Kuznetsova A. A. Kladova O. A. Barthes Nicolas P. F. Michel Benoit Y. Burger Alain Fedorova O. S. Kuznetsov N. A. 《Russian Journal of Bioorganic Chemistry》2019,45(6):591-598
Russian Journal of Bioorganic Chemistry - DNA-substrates containing fluorescent DNA base analogs are widely used to study protein–nucleic acid interactions. In the case of DNA-recognizing... 相似文献
56.
Zlobin I. E. Kartashov A. V. Kuznetsov Vl. V. 《Russian Journal of Plant Physiology》2019,66(4):591-596
Russian Journal of Plant Physiology - It is well known that excessive zinc accumulation is harmful to plant cells. Though, it is uncertain at which levels of intracellular availability zinc begins... 相似文献
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Lunina O. N. Savvichev A. S. Babenko V. V. Boldyreva D. I. Kuznetsov B. B. Kolganova T. V. Krasnova E. D. Kokryatskaya N. M. Veslopolova E. F. Voronov D. A. Demidenko N. A. Letarova M. A. Letarov A. V. Gorlenko V. M. 《Microbiology》2019,88(1):100-114
Microbiology - The community of anoxygenic phototrophic bacteria (APB) from the water column of the meromictic Lake Trekhtsvetnoe (Kandalaksha Bay, White Sea, Russia) was studied in March 2012 and... 相似文献
59.
Permyakova Natalya V. Sidorchuk Yury V. Marenkova Tatyana V. Khozeeva Sofya A. Kuznetsov Vitaly V. Zagorskaya Alla A. Rozov Sergei M. Deineko Elena V. 《Molecular biology reports》2019,46(6):5735-5743
Molecular Biology Reports - Targeted genome editing using CRISPR/Cas9 is a promising technology successfully verified in various plant species; however, it has hardly been used in plant cell... 相似文献
60.
D. G. Gubin Т. N. Malishevskaya Y. S. Astakhov S. Y. Astakhov G. Cornelissen V. A. Kuznetsov 《Chronobiology international》2019,36(4):564-577
Advanced primary open-angle glaucoma (POAG) is characterized by progressive retinal ganglion cell complex (RGCC) damage that may cause subsequent disruption of the circadian rhythms. Therefore, we evaluated circadian body temperature (BT) rhythm and sleep characteristics of 115 individuals (38 men and 77 women) diagnosed with POAG. GLV (global loss volume; %), a measure of RGCC damage, was estimated by high-definition optical coherence tomography, and RGC functional ability was assessed by pattern electroretinogram amplitude (PERGA). Depending on dynamics of POAG progression criteria, two groups were formed that were distinctively different in GLV: Stable POAG group (S-POAG; GLV = 5.95 ± 1.84, n = 65) and Progressive POAG group (P-POAG; GLV = 24.27 ± 5.09, n = 50). S-POAG and P-POAG groups were not different in mean age (67.61 ± 7.56 versus 69.98 ± 8.15) or body mass index (24.66 ± 3.03 versus 24.77 ± 2.90). All subjects performed 21 around-the-clock BT self-measurements during a 72-h period and kept activity/sleep diaries. Results showed pronounced disruption of circadian physiology in POAG and its progression with increasing severity of the disease. The daily mean of BT was unusually low, compared to age-matched controls. Moreover, our results revealed distinctive features of BT circadian rhythm alterations in POAG development and POAG progression. S-POAG is associated with lowered BT circadian rhythm robustness and inter-daily phase stability compared to controls. In the P-POAG group, the mean phase of the circadian BT rhythm was delayed by about 5 h and phases were highly scattered among individual patients, which led to reduced group mean amplitude. Circadian amplitudes of individuals were not different between the groups. Altogether, these results suggest that the body clock still works in POAG patients, but its entrainment to the 24-h environment is compromised. Probably because of the internal desynchronization, bedtime is delayed, and sleep duration is accordingly shortened by about 55 min in P-POAG compared to S-POAG patients. In the entire POAG cohort (both groups), later sleep phase and shorter mean sleep duration correlate with the delayed BT phase (r = 0.215; p = 0.021 and r = 0.322; p = 0.0004, respectively). An RGCC GLV of 15% apparently constitutes a threshold above which a delay of the circadian BT rhythm and a shortening of sleep duration occur. 相似文献