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Thomas Gautier Willeke de Haan Jacques Grober Dan Ye Matthias J. Bahr Thierry Claudel Niels Nijstad Theo J. C. Van Berkel Louis M. Havekes Michael P. Manns Stefan M. Willems Pancras C. W. Hogendoorn Laurent Lagrost Folkert Kuipers Miranda Van Eck Patrick C. N. Rensen Uwe J. F. Tietge 《Journal of lipid research》2013,54(8):2195-2205
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Paul Schweiger Harald Gross Jessica Zeiser Uwe Deppenmeier 《Applied microbiology and biotechnology》2013,97(8):3475-3484
Two genes encoding recombinant cytosolic oxidoreductases from Gluconobacter oxydans, gox0313 and gox0646, were heterologously expressed in Escherichia coli and the resulting proteins were purified and characterized. GOX0313 was identified as a medium-chain alcohol dehydrogenase, whereas GOX0646 was classified as a ketocarbonyl reductase. GOX0313 had a broad substrate spectrum and oxidized various primary alcohols. However, GOX0313 had a preference for substrate reduction, reducing many aldehydes and α-diketones. In contrast, GOX0646 had a narrow substrate spectrum and reduced α-diketones, preferring short-chain ketocarbonyls. Both enzymes regio- and stereospecifically reduced α-diketones to the corresponding (S)-hydroxy ketone, as shown by NMR. These products are difficult to produce chemically, requiring complicated protecting group chemistry. Furthermore, hydroxy ketones find industrial application in the production of pheromones, fragrances, flavors, and pharmaceuticals. Hence, these enzymes are interesting biocatalysts for the production of enantiomerically pure building blocks that are difficult to prepare chemically. 相似文献
997.
Randolf Menzel Uwe Greggers 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2013,199(10):867-873
Animal navigation is guided by multiple sensory cues. Here, we ask whether and how olfactory stimuli emanating from places other than the trained feeding site redirect the flight paths of honeybees. The flight trajectories of individual bees were registered using harmonic radar tracking. Sensory cues (compass direction, distance, visual cues en route and close to the feeding site) associated with the trained flight route dominated wayfinding, but a learned odorant carried by air flow induced excursions into the wind. These redirections were largely restricted to rather small deviations from the trained route (<60°, <200 m) and occurred only if the animal did not receive the trained odorant stimulus at the trained feeding site. Under certain conditions, larger excursions were observed. These findings are discussed in the context of odor guidance of honeybees over longer distances (>300 m from the hive). 相似文献
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Marchel Stuiver Sergio Lainez Constanze Will Sara Terryn Dorothee Günzel Huguette Debaix Kerstin Sommer Kathrin Kopplin Julia Thumfart Nicole B. Kampik Uwe Querfeld Thomas E. Willnow Vladimír Němec Carsten A. Wagner Joost G. Hoenderop Olivier Devuyst Nine V.A.M. Knoers René J. Bindels Iwan C. Meij Dominik Müller 《American journal of human genetics》2011,(3):S101
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Manfred Georg Moertl Helmut Karl Lackner Ilona Papousek Andreas Roessler Helmut Hinghofer-Szalkay Uwe Lang Vassiliki Kolovetsiou-Kreiner Dietmar Schlembach 《PloS one》2013,8(4)