一株胞内合成纳米磁性颗粒菌株的筛选及鉴定

【目的】从聊城东昌湖湖水中分离纯化出一株可合成纳米磁性颗粒的菌株，将其命名为TZ-1。【方法】对该菌株进行形态学研究、分子生物学鉴定，将TZ-1菌株合成的纳米磁性颗粒进行提取纯化，并对菌体和纳米磁性颗粒进行透射电镜(transmission electron microscope，TEM)观察、扫描电镜(Scanning electron microscope，SEM)元素分析，对纳米磁性颗粒进行X射线衍射(X-ray diffraction，XRD)分析。【结果】经鉴定TZ-1属于伯克霍尔德氏菌属(Burkholderia sp.)。透射电镜下菌体为杆状，易聚集，有明显的单生鞭毛，有荚膜，在TEM下观察菌体内部有两种电子致密颗粒，较小颗粒分布在菌体细胞膜附近，近似多边形，大小约为60 nm，较大颗粒分布在菌体内部，大小约为180 nm，表面有膜包裹。扫描电镜(SEM)下细胞为杆状，大小与TEM下测量结果一致。SEM下对磁性颗粒进行元素分析，主要为Fe、P、O。根据TEM、SEM、XRD结果推测菌体可合成纳米磁性颗粒。【结论】分离纯化出的菌株TZ-1可合成纳米磁性颗粒，磁性颗粒X射线衍射结果分析知TZ-1合成的纳米磁性颗粒为单斜晶体，主要成分为Fe3(PO4)2·8H2O和Fe3O4。

Isolation and characterization a bacterium strain can synthesized magnetic nano-particles

Objective] Isolation of a bacterium strain named TZ-1 synthesized magnetic nano-particles from Dongchang Lake in Liaocheng City. Methods] Proceed the morphological study and 16S rRNA gene identify to the strain TZ-1, extract and depurate the magnetic nano-particles form TZ-1 culture. Observe and analyze TZ-1 cells and the magnetic nano-particles through transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction (XRD). Results] Concluded that TZ-1 belongs to Burkholderia sp.. The cells of TZ-1 is rod under the TEM, possess flagellum and capsule easy to gather. The approximate polygon in like electron dense granules arounded biomembrane in the cells include two types in size for 60 nm approximate located at the cytomembrane and 180 nm approximate located inner the middle of cells. The cells are rod under SEM, and the sizes are the same as the TEM. EDAX spectrum for the magnetic nano-particles on SEM shows that the main elements are Fe, P, O. According to the result of TEM, SEM and XRD that TZ-1 can compose magnetic nano-particles. Conclusion] The bacterial strain TZ-1 we isolated synthesized magnetic nano-particles, XRD shows the ingredient of the magnetic nano-particles are Fe3(PO4)2·8H2O and Fe3O4, and the crystal structure of the magnetic nano-particles is monoclinic crystal.