US-France Cooperative Research: Evolution and Function of Hopanoid Lipids in Symbiotic and Thermoacidophilic Actinomycetes

这项为期三年的美法微生物遗传学合作奖涉及加州大学戴维斯分校的艾莉森·M·贝里和克劳德·伯纳德-里昂第一大学的菲利普·诺曼德和他们的学生。目的是研究Frankia的生物学，这是一种形成根瘤共生体的固氮原核生物，并解决一个关键的代谢控制点，即类霍帕尼类脂肪的生物合成途径。Frankia产生特定的霍帕尼类脂质是一种关键微生物，因为它在给一组相关的固氮植物结瘤方面与革兰氏阴性根瘤菌相似。Frankia与嗜热嗜酸嗜酸纤维素菌有关。他们将通过(1)来自Frankia基因组克隆的17kb DNA序列信息和近亲的相应基因：(2)Frankia Hopanid类脂与A.Cellulyticus的比较；以及(3)对嗜热放线菌的环境采样和Hopanlike基因的表达，探索Hopanoid在共生固氮和作为对环境胁迫的适应中的作用。在这一合作中获得的信息将被用于扩展研究在极端环境条件下和通过共生信号化合物合成类霍帕宁的进化和功能。这位美国研究人员将霍帕尼类脂质及其在Frankia固氮中的重要性方面的专业知识带到了这次合作中。法国在弗兰克氏菌系统发育和使用分子遗传工具研究土壤微生物群落方面的专门知识对此起到了补充作用。这个小组也有能力对Frankia进行蛋白质组学分析。该奖项代表了美方向NSF和法国国家科学研究中心(CNRS)提出的联合建议。NSF将支付这名美国调查员和研究生的旅费和生活费。CNRS将支持法国研究人员和学生访问美国。美国学生将受益于与国际研究团队交流科学技术和经验。

0233366BerryThis three-year award for US-France collaboration in microbial genetics involves Alison M. Berry of the University of California at Davis and Philippe Normand of the University of Claude Bernard - Lyon 1 and their students. The objectives are to study the biology of Frankia, a nitrogen-fixing prokaryote that forms root nodule symbioses and to address a key metabolic control point, the hopanoid lipid biosynthetic pathway. The production of specific hopanoid lipids in Frankia is a pivotal microorganism in that it is similar to the gram-negative rhizobia in its capacity to nodulate a group of related nitrogen-fixing plants. Frankia is related to thermoacidophilic Acidothermus cellulyticus. They will explore the role of hopanoids in symbiotic nitrogen fixation and as an adaptation to environmental stress through (1) DNA sequence information from the 17-kb Frankia genomic clone, and corresponding genes in close relatives: (2) comparisons of the profile of Frankia hopanoid lipids with that of A. Celluloyticus; and (3) environmental sampling of the thermoacidophilic actinomycetes, and expression of hopanoid genes. The information obtained in this collaboration will be used in expanded investigations of the evolution and function of hopanoid synthesis under extreme environmental conditions and by symbiotic signaling compounds. The US investigator brings to this collaboration expertise in hopanoid lipids and their importance in nitrogen fixation in Frankia. This is complemented by French expertise in Frankia phylogeny and in the use of molecular genetic tools for examining microbial communities in soils. This group also has the capacity to do proteomic analysis of Frankia. This award represents the US side of a joint proposal to the NSF and the French National Center for Scientific Research (CNRS). NSF will cover travel funds and living expenses for the US investigator and graduate students. The CNRS will support the visits of the French researchers and students to the United States. US students will benefit from the exchange of scientific techniques and experience with an international research team.