CIL:7321, Escherichia coli, prokaryotic cell. In Cell Image Library

This is one of four related images of F-pili (conjugative pili encoded by the F plasmid of E. coli) dynamics by live-cell imaging. There are 2 movie (.avi) files and 2 files (.tiff) from the movies. The movies show that F-pili normally undergo cycles of extension and retraction in the absence of any obvious triggering event such as contact with a recipient cell.

Retraction of an F-pilus. E. coli strain HfrH expressing the red fluorescent marker DsRed Express were mixed with R17 bacteriophage labeled with Alexa 488 (green); R17 bacteriophage (NCBITaxon:12026) bind to the sides of F-pili.

Samples were imaged by using a Zeiss LSM 510 confocal microscope with a Plan-Apochromat 63 × 1.4 N.A. DIC objective. Alexa-488 was excited with the 488-nm line of an argon laser with a 505–530-nm filter for emission, and DsRed was excited with the 543-nm line of a HeNe laser, with a 560-nm long pass filter for emission. An HFT UV/488/543 beam splitter was used. Images were collected in a single focal plane at 2 s intervals and accompanying movies (.avi) are playing at 10fps.

本数据集为大肠杆菌F质粒编码的接合性菌毛（F-pili）活细胞动态成像相关四组图像之一。本次提供的内容包含2个AVI格式视频文件与2个源自该视频的TIFF格式文件。视频结果显示，在未出现受体细胞接触这类明确触发事件的情况下，F菌毛通常会经历延伸与回缩的循环过程。

本示例展示F菌毛的回缩过程：将表达红色荧光标记物DsRed Express的大肠杆菌HfrH菌株，与经Alexa 488标记的绿色荧光R17噬菌体混合；R17噬菌体（NCBITaxon:12026）可结合于F菌毛的侧面。

成像采用蔡司LSM 510共聚焦显微镜（Zeiss），搭配Plan-Apochromat 63× 1.4 N.A. DIC物镜。Alexa 488通过氩离子激光器的488nm激发线激发，发射光采集使用505–530nm滤光片；DsRed通过氦氖激光器的543nm激发线激发，发射光采集使用560nm长通滤光片。系统采用HFT UV/488/543分色镜。图像以单焦平面采集，采集间隔为2秒，配套AVI格式视频以10fps（每秒10帧）的速率播放。