Tuesday, August 08, 2006
When it comes to tiny motors, the flagella used by bacteria to get around their microscopic worlds are hard to beat. Composed of several tens of different types of protein, a flagellum (that's the singular) rotates about in much the same way that a rope would spin if mounted in the chuck of an electric drill, but at much higher speeds-about 300 revolutions per second.
Biologists at the California Institute of Technology have now succeeded for the first time in obtaining a three-dimensional image of the complete flagellum assembly using a new technology called electron cryotomography. Reporting in Nature, the scientists show in unprecedented detail both the rotor of the flagellum and the stator, or protein assembly that not only attaches the rotor to the cell wall, but also generates the torque that serves to rotate it.
The accomplishment is a tour de force within the field of structural biology, through which scientists seek to understand how cells work by determining the shapes and configurations of the proteins that make them up. The results could lead to better-designed nanomachines.
No subscription is necessary at the moment because its an "advance publication". (NB The PhysOrg report does give a link to the full text but it has a typo in it - one of my usual tricks!)
John Latter / Jorolat
technorati tags: flagella, bacteria, microscopic, protein, california, institute, technology, flagellum, electron, cryotomography, nature, rotor, stator, structural, biology, nanomachines, evolution, evolution+research, john+latter, jorolat