There are many different mechanisms of bacterial motility, by gliding motility has always been something of a mystery. It turns out that in Mycoplasma, gliding motility results from many tiny legs pedalling away like crazy. Cute, wait until the nanotech guys gets hold of this one. Oh wait, they already did.
Unique centipede mechanism of Mycoplasma gliding. Ann Rev Microbiol. (2010) 64: 519-537
Mycoplasma, a genus of pathogenic bacteria, forms a membrane protrusion at a cell pole. It binds to solid surfaces with this protrusion and then glides. The mechanism is not related to known bacterial motility systems, such as flagella or pili, or to conventional motor proteins, including myosin. We have studied the fastest species, Mycoplasma mobile, and have proposed a working model as follows. The gliding machinery is composed of four huge proteins at the base of the membrane protrusion and supported by a cytoskeletal architecture from the cell inside. Many flexible legs approximately 50 nm long are sticking out from the machinery. The movements generated by the ATP hydrolysis cell inside are transmitted to the “leg” protein through a “gear” protein, resulting in repeated binding, pull, and release of the sialylgalactose fixed on the surface by the legs. The gliding of Mycoplasma pneumoniae, a species distantly related to M. mobile, is also discussed.
- Cytoskeletal structure of Mycoplasma mobile
- Bacterial Gliding Motility: Multiple Mechanisms for Cell Movement over Surfaces. (2007) Ann. Rev. Microbiol. 55: 49-75