Systematic Structural Analyses of Attachment Organelle in Mycoplasma pneumoniae

PLoS Pathogens

Lisa Matsuo¹  Makoto Miyata²  Daisuke Nakane²  Tsuyoshi Kenri³ 

[1] Department of Bacteriology II, National Institute of Infectious Diseases, Musashimurayama, Tokyo, Japan;Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan;Department of Physics, Faculty of Science, Gakushuin University, Tokyo, Japan

关键词: Cellular structures;    organelles;    Yellow fluorescent protein;    Fluorescence imaging;    Mycoplasma pneumoniae;    Electron microscopy;    Adhesins;    Protein structure;    Centrifugation;   

DOI  :  10.1371/journal.ppat.1005299

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

Mycoplasma pneumoniae, a human pathogenic bacterium, glides on host cell surfaces by a unique and unknown mechanism. It forms an attachment organelle at a cell pole as a membrane protrusion composed of surface and internal structures, with a highly organized architecture. In the present study, we succeeded in isolating the internal structure of the organelle by sucrose-gradient centrifugation. The negative-staining electron microscopy clarified the details and dimensions of the internal structure, which is composed of terminal button, paired plates, and bowl complex from the end of cell front. Peptide mass fingerprinting of the structure suggested 25 novel components for the organelle, and 3 of them were suggested for their involvement in the structure through their subcellular localization determined by enhanced yellow fluorescent protein (EYFP) tagging. Thirteen component proteins including the previously reported ones were mapped on the organelle systematically for the first time, in nanometer order by EYFP tagging and immunoelectron microscopy. Two, three, and six specific proteins localized specifically to the terminal button, the paired plates, and the bowl, respectively and interestingly, HMW2 molecules were aligned parallel to form the plate. The integration of these results gave the whole image of the organelle and allowed us to discuss possible gliding mechanisms.

【 授权许可】

CC BY