Conformational Spread as a Mechanism for Cooperativity in the Bacterial Flagellar Switch.
- Resource Type
- Article
- Authors
- Fan Bai; Branch, Richard W.; Nicolau Jr., Dan V.; Pilizota, Teuta; Steel, Bradley C.; Maini, Philip K.; Berry, Richard M.,
- Source
- Science; 2/5/2010, Vol. 327 Issue 5966, p685-689, 5p
- Subject
- Research methodology
Allosteric regulation
Cell motility
Chemotaxis
Conformational analysis
Microscopy
Cell communication
- Language
- ISSN
- 00368075
The bacterial flagellar switch that controls the direction of flagellar rotation during chemotaxis has a highly cooperative response. This has previously been understood in terms of the classic two-state, concerted model of allosteric regulation. Here, we used high-resolution optical microscopy to observe switching of single motors and uncover the stochastic multistate nature of the switch. Our observations are in detailed quantitative agreement with a recent general model of allosteric cooperativity that exhibits conformational spread—the stochastic growth and shrinkage of domains of adjacent subunits sharing a particular conformational state. We expect that conformational spread will be important in explaining cooperativity in other large signaling complexes. [ABSTRACT FROM AUTHOR]