2010年6月25号法国科研中心、地中海微生物研究所，细菌化学实验室任主任L.F.Wu研究员访问海洋生物技术实验室，并作了关于海洋磁细菌的精彩报告，同时进行了深入交流。

报告题目：Magnetotaxis mechanism of marine magnetotactic bacteria
报告人：Prof.Long-Fei Wu
Laboratoire de Chimie Bactérienne, UPR9043, Université de la Méditerranée Aix-Marseille II, Institut de Microbiologie de la Méditerranée, CNRS, F-13402 Marseille Cedex 20, France
报告时间：6月25号（周五）下午1:30
报告地点：生命学院3-105
Abstract：
Magnetotactic bacteria (MTB) comprise a heterogeneous group of gram-negative bacteria found mainly in the oxic-anoxic transition zone (OATZ) of limnic or marine sediments. MTB synthesize unique intracellular structures: magnetosomes, comprising a magnetic single-domain crystal surrounded by a membrane. With the help of the cytoskeletal protein MamK, they arrange in a chain along the long axis of spirilla, and impart a net magnetic-dipole moment to the bacterium,allowing it to align along geomagnetic field lines. MTB are reported always swim downward in stratified water column or sediments, that is exclusively northward in parallel with the geomagnetic field lines (north-seeking NS) on the Northern Hemisphere, and anti-parallel with the geomagnetic field lines toward the magnetic south pole (south-seeking SS) on the Southern Hemisphere. Therefore, magnetotaxis is thought to guide cells in each hemisphere downward to less oxygenated regions of aquatic habitats where they would presumably stop swimming until conditions change. The behaviors have been referred to as magneto-aerotaxis. Using magneto-ovoid MO-1 strain,that we have isolated from the Mediterranean Sea, as a model we showed that redox gradient configuration in combination with magnetic field direction are determinant factors that select the magnetotactic polarity of a MTB population. In fact, NS and SS cells could obviously coexist, when the oxidation-reduction gradient configuration is suitable, in the northern geomagnetic field. The ‘passive alignment’model is conceivable for magneto-spirilla and magneto-bacilli, whereas it cannot account for magnetotaxis of MO-1.As they translate along as well as rotate around their short body axis, MO-1 cells display a helical trajectory of swim along the magnetic field lines. Together with our results obtained in the study of magnetotaxis of /Magnetospirillum/, we propose that MTB adjust actively the flagellar rotation in response to change in magnetic torque.

报告人简介：
  吴龙飞(L.F.Wu)：1988年在法国应用科学研究所获得博士学位。1990年起受聘于法国科研中心。现在法国科研中心、地中海微生物研究所，细菌化学实验室任主任研究员。中国科学院海外评审专家、海外知名学者。中国海洋大学兼职教授，中科院海洋研究所客座教授。中国国家杰出青年基金获得者。
  1990-1995年研究镍在细菌中的代谢和镍的生物学功能。发现高亲合镍输送系统（Nik）、并揭示镍调控NikR蛋白，对镍-铁氢酶进行了系统的研究。1995年开始研究蛋白质在细菌中的转位机理，发现了TAT折叠蛋白质输送系统。2003年开始研究趋磁细菌，分离得到首株地中海趋磁细菌纯培养。