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Exploring Biotic and Abiotic Determinants of Nest Size in Mediterranean Great Tits (Parus major) and Blue Tits (Cyanistes caeruleus) 下载免费PDF全文
Marcel M. Lambrechts Jacques Blondel Cyril Bernard Samuel P. Caro Anne Charmantier Virginie Demeyrier Claire Doutrelant Gabrielle Dubuc‐Messier Amélie Fargevieille Christophe de Franceschi Pablo Giovannini Arnaud Grégoire Sylvie Hurtrez‐Boussès Annick Lucas Mark C. Mainwaring Pascal Marrot Adèle Mennerat Samuel Perret Philippe Perret 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(6):492-501
934.
Georg Wolff Christoph Hagen Kay Grünewald Rainer Kaufmann 《Biology of the cell / under the auspices of the European Cell Biology Organization》2016,108(9):245-258
Correlative light and electron microscopy (CLEM) has become a powerful tool in life sciences. Particularly cryo‐CLEM, the combination of fluorescence cryo‐microscopy (cryo‐FM) permitting for non‐invasive specific multi‐colour labelling, with electron cryo‐microscopy (cryo‐EM) providing the undisturbed structural context at a resolution down to the Ångstrom range, has enabled a broad range of new biological applications. Imaging rare structures or events in crowded environments, such as inside a cell, requires specific fluorescence‐based information for guiding cryo‐EM data acquisition and/or to verify the identity of the structure of interest. Furthermore, cryo‐CLEM can provide information about the arrangement of specific proteins in the wider structural context of their native nano‐environment. However, a major obstacle of cryo‐CLEM currently hindering many biological applications is the large resolution gap between cryo‐FM (typically in the range of ~400 nm) and cryo‐EM (single nanometre to the Ångstrom range). Very recently, first proof of concept experiments demonstrated the feasibility of super‐resolution cryo‐FM imaging and the correlation with cryo‐EM. This opened the door towards super‐resolution cryo‐CLEM, and thus towards direct correlation of structural details from both imaging modalities. 相似文献
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The plant‐specific CDKB1‐CYCB1 complex mediates homologous recombination repair in Arabidopsis 下载免费PDF全文
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Concetta De Santi Hanna-Kirsti S. Leiros Alessia Di Scala Donatella de Pascale Bjørn Altermark Nils-Peder Willassen 《Extremophiles : life under extreme conditions》2016,20(3):323-336
A gene encoding an esterase, ThaEst2349, was identified in the marine psychrophilic bacterium Thalassospira sp. GB04J01. The gene was cloned and overexpressed in E. coli as a His-tagged fusion protein. The recombinant enzyme showed optimal activity at 45 °C and the thermal stability displayed a retention of 75 % relative activity at 40 °C after 2 h. The optimal pH was 8.5 but the enzyme kept more than 75 % of its maximal activity between pH 8.0 and 9.5. ThaEst2349 also showed remarkable tolerance towards high concentrations of salt and it was active against short-chain p-nitrophenyl esters, displaying optimal activity with the acetate. The enzyme was tested for tolerance of organic solvents and the results are suggesting that it could function as an interesting candidate for biotechnological applications. The crystal structure of ThaEst2349 was determined to 1.69 Å revealing an asymmetric unit containing two chains, which also is the biological unit. The structure has a characteristic cap domain and a catalytic triad comprising Ser158, His285 and Asp255. To explain the cold-active nature of the enzyme, we compared it against thermophilic counterparts. Our hypothesis is that a high methionine content, less hydrogen bonds and less ion pairs render the enzyme more flexible at low temperatures. 相似文献
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Köse Çınar Rugül Görgülü Yasemin Çalıyurt Okan Sönmez Bülent 《Sleep and biological rhythms》2016,14(4):387-396
Sleep and Biological Rhythms - Sleep deprivation (SD) is known to modulate inflammatory and oxidative stress markers. How these markers change over the SD period have seldom been studied in healthy... 相似文献
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TERMINAL FLOWER1 is a breeding target for a novel everbearing trait and tailored flowering responses in cultivated strawberry (Fragaria × ananassa Duch.) 下载免费PDF全文