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101.
102.
Yakata K Hiroaki Y Ishibashi K Sohara E Sasaki S Mitsuoka K Fujiyoshi Y 《Biochimica et biophysica acta》2007,1768(3):688-693
Recently, two novel mammalian aquaporins (AQPs), AQPs 11 and 12, have been identified and classified as members of a new AQP subfamily, the "subcellular AQPs". In members of this subfamily one of the two asparagine-proline-alanine (NPA) motifs, which play a crucial role in selective water conduction, are not completely conserved. Mouse AQP11 (mAQP11) was expressed in Sf9 cells and purified using the detergent Fos-choline 10. The protein was reconstituted into liposomes, which were used for water conduction studies with a stopped-flow device. Single water permeability (pf) of AQP11 was measured to be 1.72+/-0.03x10(-13) cm(3)/s, suggesting that other members of the subfamily with incompletely conserved NPA motifs may also function as water channels. 相似文献
103.
Stine Louring Nielsen Michael Finbarr Mullins Lars Brorson Fich Kirsten Kaya Roessler 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2017,30(4):310-327
Focusing on the interactional aspects of art in health interventions, we qualify guidelines for art in hospitals. Patients in this user-oriented study primarily ranked items to favor figurative art painted in light colors; however both figurative and abstract art in light and dark colors figured among the highest ratings. The role of spatial context, motif, color and shapes seems to have an effect on patients’ experience of a hospital stay. This article draws attention to the application of visual art as a source of stimulus and healing—and a means to affect patient satisfaction in hospitals. 相似文献
104.
Mohamed Faraj Edbeib Roswanira Abdul Wahab Yilmaz Kaya Fahrul Huyop 《Annals of microbiology》2017,67(5):371-382
Halogenated compounds represent potential long-term threats to human well-being and health and, therefore, the quest for microorganisms capable of degrading these hazardous substances merits urgent consideration. We have isolated a novel dehalogenase-producing bacterium from the hypersaline environment of Tuz Gölü Lake, Turkey and subsequently identified this isolate as Pseudomonas halophila HX. Under optimal culture conditions (pH 8.0, 15% NaCl, 30 °C, 200 rpm, 96 h culture time), the strain almost completely degraded (99.3%) 2,2-dichloropropionic acid (20 mM). The dehalogenase gene (dehHX) of the bacterium was amplified by PCR, and the deduced amino acid sequence of the DehHX was found to belong to a Group I dehalogenase and to share an 82% sequence identity to the dehalogenase DehI of Pseudomonas putida strain PP3. Interestingly, the pI of DehHX was more acidic (pI 3.89) than those of the non-halophilic dehalogenases (average measured pI 5.95). Homology-based structural modeling revealed that the surface of DehHX was unusually negatively charged due to the higher presence of acidic residues, which accounts for the uncommonly low pI seen in DehHX and explains the mechanism of adaptation that contributes to the exceptional halotolerance of the enzyme. The excess surface acidic residues were beneficial in enhancing the water-binding capacity, a crucial feature for preserving the stability and solubility of DehHX in highly saline conditions. In summary, we suggest that bio-prospecting for halogenated compound-degrading microorganisms in highly saline environments is a practical and safe strategy for the bioremediation of contaminated coastal areas. 相似文献
105.
Asiye Ciftci Hüseyin Karatay Filiz Kücükosmanoğlu Alptekin Karahan Zeki Kaya 《Tree Genetics & Genomes》2017,13(3):69
The European black poplar (Populus nigra L.) is an ecologically and economically important tree species for Turkey. The important and major genetic resources of species for future breeding and ex situ conservation purposes have been archived in a clone bank in Ankara by selecting clones from natural populations and old plantations throughout Turkey. There is no study to date assessing genetic composition these materials. Two-hundred-thirty-three P. nigra clones from six geographic region of Turkey (clone collection populations), and 32 trees from two natural populations (Tunceli and Melet) were genotyped by using 12 nuclear microsatellite DNA markers. There were nine clones which duplicated in various frequencies. The analysis carried out with removal of the duplicated clones revealed a moderately high genetic diversity in studied populations. The observed heterozygosities ranged from 0.59 in Tunceli natural to 0.69 in Central Anatolia clone collection populations. In general, there was excess of heterozygosity in the studied populations. Populations composed of clone collections were significantly differentiated from natural populations (F ST = 0.17), while there was little differentiation among those populations in the clone collection (F ST = 0.03). Two distantly located natural populations with small sizes also differed from each other (F ST = 0.17). Genetic structure analysis revealed two distinct groups (clone collection vs natural populations) with very high membership values (>92%). Clone collection populations had high level of admixture while natural populations had homogenous genetic structure. The presence of large number of clonal duplication, reduced genetic differentiation, and high level of admixture in clone collection populations indicate that genetic resources of European black poplar were highly degraded through genetic erosion and pollution caused by intensive cultural practices and extensive dispersal of clonal materials. To understand genetic diversity and its structural pattern thoroughly in the six clone collection populations, a further study with extensive and systematic sampling of European black poplar populations in major river ecosystems in Turkey will be useful. 相似文献
106.
Oily water treatment has attracted the attention of many researchers.The development of effective and cheap oil/water separation materials is urgent for treating this problem.Herein,inspired by superhydrophobic typical plant leaves such as lotus,red rose and marigold,superhydrophobic and superoleophilic copper mesh was fabricated by etching and then surface modification with 1-dodecanethiol (HS(CH2)11CH3).A rough silver layer is formed on the mesh surface after immersion.The obtained mesh surface exhibits superhydrophobicity and superoleophilicity and the static water contact angle was 153° ± 3°.In addition,the as-prepared copper mesh shows self-cleaning character with water and chemical stability.The as-prepared copper foam can easily remove the organic solvents either on water or underwater.We demonstrate that by using the as-prepared mesh,oils can be absorbed and separated,and that high separation efficiencies of larger than 92% are retained for various oils.Thus,such superhydrophobic and superoleophilic copper mesh is a very promising material for the application of oil spill cleanup and industrial oily wastewater treatment. 相似文献
107.
Borrelia burgdorferi infection is the most frequent tick-transmitted disease worldwide. Our aim was to assess the seroprevalence of B. burgdorferi infection among forestry workers and farmers in Duzce, in the north-west region of Turkey. Blood samples from 349 forestry workers and farmers and 193 healthy blood donors were obtained to determine the presence of antibodies to B. burgdorferi. A two-step testing strategy was used; the sera were initially tested by ELISA and then by Western blot (WB) IgG. Demographic data regarding residence, age, gender, profession, tick bite history, contact with animals, and symptoms involving the skin, nervous system, and osteoarticular system were collected by questionnaire. All results were evaluated statistically using the chi2 test. The seroprevalence of B. burgdorferi was 10.9% (n=38) in forestry workers and farmers and 2.6% (n=5) in blood donors by ELISA, with a statistically significant difference (p<0.001). Seropositivity rates were related to age, gender, and common risk factors for the disease. IgG seropositivity was confirmed in four (1.1%) sera by WB. In this first seroepidemiological report from the northwest region of Turkey, tick bite exposure was found to be high, whereas B. burgdorferi infection was not common. Preventive measures against tick exposure and further studies to determine the distribution of Lyme disease in Turkey are proposed. 相似文献
108.
Protein quality control during aging involves recruitment of the macroautophagy pathway by BAG3
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Martin Gamerdinger Parvana Hajieva A Murat Kaya Uwe Wolfrum F Ulrich Hartl Christian Behl 《The EMBO journal》2009,28(7):889-901
The Hsc/Hsp70 co-chaperones of the BAG (Bcl-2-associated athanogene) protein family are modulators of protein quality control. We examined the specific roles of BAG1 and BAG3 in protein degradation during the aging process. We show that BAG1 and BAG3 regulate proteasomal and macroautophagic pathways, respectively, for the degradation of polyubiquitinated proteins. Moreover, using models of cellular aging, we find that a switch from BAG1 to BAG3 determines that aged cells use more intensively the macroautophagic system for turnover of polyubiquitinated proteins. This increased macroautophagic flux is regulated by BAG3 in concert with the ubiquitin-binding protein p62/SQSTM1. The BAG3/BAG1 ratio is also elevated in neurons during aging of the rodent brain, where, consistent with a higher macroautophagy activity, we find increased levels of the autophagosomal marker LC3-II as well as a higher cathepsin activity. We conclude that the BAG3-mediated recruitment of the macroautophagy pathway is an important adaptation of the protein quality control system to maintain protein homeostasis in the presence of an enhanced pro-oxidant and aggregation-prone milieu characteristic of aging. 相似文献
109.
Structure-functional characterization of vitamin D receptor (VDR) requires identification of structurally distinct areas of VDR-ligand-binding domain (VDR-LBD) important for biological properties of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3). We hypothesized that covalent attachment of the ligand into VDR-LBD might alter ‘surface structure’ of that area influencing biological activity of the ligand. We compared anti-proliferative activity of three affinity alkylating derivatives of 1,25(OH)2D3 containing an alkylating probe at 1,3 and 11 positions. These compounds possessed high-affinity binding for VDR; and affinity labeled VDR-LBD. But, only the analog with probe at 3-position significantly altered growth in keratinocytes, compared with 1,25(OH)2D3. Molecular models of these analogs, docked inside VDR-LBD tentatively identified Ser237 (helix-3: 1,25(OH)2D3-1-BE), Cys288 (β-hairpin region: 1,25(OH)2D3-3-BE,) and Tyr295 (helix-6: 1,25(OH)2D3-11-BE,) as amino acids that are potentially modified by these reagents. Therefore, we conclude that the β-hairpin region (modified by 1,25(OH)2D3-3-BE) is most important for growth inhibition by 1,25(OH)2D3, while helices 3 and 6 are less important for such activity. 相似文献
110.
Murat Kaya Elisabeth A. Herniou Timothy G. Barraclough 《Organisms Diversity & Evolution》2009,9(1):3-12
Microscopic animals offer great potential in the analysis of spatial patterns of diversity, as they may provide different scenarios for biogeography and macroecology, but understanding diversity of microscopic animals is hampered by lack of comprehensive data on species distribution and by unreliable taxonomy. DNA taxonomy may prove useful in obtaining reliable data in the future, but we still do not know to what extent traditional and DNA taxonomy can be comparable for microscopic organisms. In this paper, we compare analyses and estimates of diversity at the level of species assemblage between traditional and DNA taxonomy for a group of moss-dwelling microscopic animals, bdelloid rotifers. The results are straightforward: Traditional species identification underestimates diversity by factors of 2 at the local and 2.5 at the regional scale. We discuss the results in the framework of current hypotheses on the distribution of microscopic animals. 相似文献