Graduate School of Frontier Biosciences, Osaka University

Japanese

Periodicity in attachment organelle revealed by electron cryotomography suggests conformational changes in gliding mechanism of Mycoplasma pneumoniae

Journal mBio 7, e00243-16 (2016)
Authors Kawamoto A (1), Matsuo L (2), Kato T (1), Yamamoto H (2), Namba K (3), Miyata M (4)

  1. Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
  2. Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan
  3. Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan Riken Quantitative Biology Center, Suita, Osaka, Japan
  4. Department of Biology, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Sumiyoshi, Osaka, Japan
Title Periodicity in attachment organelle revealed by electron cryotomography suggests conformational changes in gliding mechanism of Mycoplasma pneumoniae
PubMed 27073090
Laboratory Protonic NanoMachine Group 〈Prof. Namba〉
Abstract Mycoplasma pneumoniae, a pathogenic bacterium, glides on host surfaces using a unique mechanism. It forms an attachment organelle at a cell pole as a protrusion comprised of knoblike surface structures and an internal core. Here, we analyzed the three-dimensional structure of the organelle in detail by electron cryotomography. On the surface, knoblike particles formed a two-dimensional array, albeit with limited regularity. Analyses using a nonbinding mutant and an antibody showed that the knoblike particles correspond to a naplike structure that has been observed by negative-staining electron microscopy and is likely to be formed as a complex of P1 adhesin, the key protein for binding and gliding. The paired thin and thick plates feature a rigid hexagonal lattice and striations with highly variable repeat distances, respectively. The combination of variable and invariant structures in the internal core and the P1 adhesin array on the surface suggest a model in which axial extension and compression of the thick plate along a rigid thin plate is coupled with attachment to and detachment from the substrate during gliding.