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杨琛 《生物工程学报》2010,26(10):1349-1356
微生物基因组学的迅速发展为从功能基因与蛋白、网络及其调控等不同的角度,全面理解与认识微生物的代谢过程、构建细胞工厂,提供了丰富的背景信息。基于基因组序列进行代谢网络重构,有助于发现新的代谢功能基因、调控元件、甚至新的代谢途径,从而优化设计细胞内从原料到产品的生物合成路线。然而,目前公共数据库平台中代谢途径基因的功能注释,许多是错误或不完整的。以下着重介绍了近年来出现的一些用于代谢途径和调控网络重构的新型比较基因组学技术,并以近期的丙酮丁醇梭菌中木糖代谢途径的重构工作为例来说明其应用。  相似文献   
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The metabotropic glutamate receptor subtype 8 (mGlu8) is presynaptically located and regulates the release of the transmitter. Dysfunctions of this mechanism are involved in the pathophysiology of different psychiatric disorders. mGlu8 deficient mice have been previously investigated in a range of studies, but the results are contradictory and there are still many open questions. Therefore, we tested mGlu8-deficient animals in different behavioral tasks that are commonly used in neuropsychiatric research. Our results show a robust contextual fear deficit in mGlu8-deficient mice. Furthermore, novel object recognition, chlordiazepoxide-facilitated extinction of operant conditioning and the acoustic startle response were attenuated by mGlu8 deficiency. We found no changes in sensory processing, locomotor activity, prepulse inhibition, phencyclidine-induced changes in locomotion or prepulse inhibition, operant conditioning, conditioned fear to a discrete cue or in animal models of innate fear and post-traumatic stress disorder. We conclude that mGlu8 might be a potential target for disorders with pathophysiological changes in brain areas where mGlu8 modulates glutamate and gamma-amino butyric acid (GABA) transmission. Our data especially point to anxiety disorders involving exaggerated contextual fear, such as generalized anxiety disorders, and to conditions with disturbed declarative memory.  相似文献   
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摘要:【目的】克隆解脂耶氏酵母(Yarrawia lipolytica)脂肪酶基因lip1,并通过密码子优化,首次实现其在毕赤酵母(Pichia pastoris)中的诱导型和组成型表达。【方法】通过PCR扩增Y. lipolytica脂肪酶基因lip1,根据P. pastoris密码子偏爱性,运用重叠延伸PCR合成改造后基因MLip1,将其分别克隆至诱导型分泌载体pPIC9K和新构建的组成型分泌载体pGAP9K上,电转至P. pastoris GS115中,G418抗性筛选得到高拷贝转化重组子,摇瓶发酵  相似文献   
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Mixed-species foraging associations may form to enhance feeding success or to avoid predators. We report the costs and consequences of an unusual foraging association between an endemic foliage gleaning tupaid (Nicobar treeshrew Tupaia nicobarica) and two species of birds; one an insectivorous commensal (greater racket-tailed drongo Dicrurus paradiseus) and the other a diurnal raptor and potential predator (Accipiter sp.). In an alliance driven, and perhaps engineered, by drongos, these species formed cohesive groups with predictable relationships. Treeshrew breeding pairs were found more frequently than solitary individuals with sparrowhawks and were more likely to tolerate sparrowhawks in the presence of drongos. Treeshrews maintained greater distances from sparrowhawks than drongos, and permitted the raptors to come closer when drongos were present. Treeshrew foraging rates declined in the presence of drongos; however, the latter may provide them predator avoidance benefits. The choice of the raptor to join the association is intriguing; particular environmental resource states may drive the evolution of such behavioural strategies. Although foraging benefits seem to be the primary driver of this association, predator avoidance also influences interactions, suggesting that strategies driving the formation of flocks may be complex and context dependent with varying benefits for different actors.  相似文献   
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Anthropologists are known to work in contexts wider than academic settings, actively engaging with people from other disciplines and professions. The lecturers in the Fashion Institute where we presently work are challenged to integrate the practical knowledge and skills originating from the fashion industry into lessons, lectures and␣projects that prepare the students for their future careers. Our own task as (anthro)pology lecturers in Intercultural Communication and Culture and Globalization courses is to engrain a broader knowledge to compliment the practical competencies required in the professional settings. An example of the practical assignments is integrating the students' knowledge of minority groups or other cultures in developing certain fashion brands that would appeal to different ethnic groups or social classes within society or be marketable abroad. The deeper knowledge of segmentation, niche markets and specific target groups helps students to orient themselves in professional situations within the fashion industry. This requires an act of translation as well as transformation in order to translate the general (such as cultural theories) into the concrete (such as examples from the fashion industry) and to transform concrete examples and cases into broader theories. This article reflects on such acts of translation and transformation as evidenced in fashion magazines such as Vogue.  相似文献   
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