|
|
RESEARCH INTERESTS
Molecular biology and genetics; signal transduction; microbiology
Intracellular and transmembrane signaling by bacterial chemoreceptors
the role of receptor clustering in signal amplification
aerotactic signaling by the E. coli Aer protein
PUBLICATIONS
Posters
Chemotactic signaling without a target acquisition domain
Conformational suppression of inter-receptor signaling defects
Crosslinking snapshots of chemoreceptor squads
Discovery of the signal transducer for aerotaxis in E. coli
Functional architecture of an aerotaxis signal transducer
Kinase-squelching mutants of chemoreceptor signaling fragments
Methylation-independent aerotaxis: How does Aer tell time?
Physical interactions between bacterial chemoreceptors
Pyrrhic suppression of chemoreceptor signaling defects
Signaling control surfaces in the CheA kinase
Signaling fragments of a bacterial chemoreceptor
Signaling interactions between bacterial chemoreceptors
My research group investigates the molecular mechanisms that proteins use
to detect and transmit sensory information. Our experimental model is the
chemotactic behavior of E. coli, which is readily amenable to
biochemical and genetic analysis and yet embodies signaling tasks, such as
stimulus-sensing, common to all signal transduction systems.
|
 |
Clockwise from top left: Electron micrograph of an E. coli cell
showing its propulsive flagellar filaments. Confocal light microscope
image of cells with fluorescent chemoreceptor clusters. Motility plates
with nonchemotactic and chemotactic colonies. Atomic structure of a trimer
of receptor dimers with cysteine reporter sites for chemical crosslinking.
| | |
Much is known about the chemotaxis machinery of E. coli, but many
fascinating mysteries remain to be solved. For example, these cells can
detect attractant or repellent changes as small as one part in a thousand
over a concentration range of more than five logs. The extraordinary
sensitivity and dynamic range of bacterial chemotactic responses seem to
depend on cooperative signaling interactions between clustered chemoreceptor
proteins. One of the principal goals of our current research activities is
to understand the architecture and operation of these chemoreceptor networks.
Our lab also investigates the ability of E. coli to track gradients of
oxygen and other electron acceptors, a behavior known as aerotaxis.
Please consult the accompanying research posters (above) for synopses of our
experimental approaches, recent results, and current views on the mechanisms
of chemotactic and aerotactic signaling in E. coli. The molecular lessons
we're learning from these relatively simple behaviors are clearly applicable
to more complex biological signaling systems.
Selected Publications
Studdert, C.A. and J.S. Parkinson (2004) Crosslinking snapshots of bacterial chemoreceptor squads. Proc. Natl. Acad. Sci. USA 101:2117-2122.
Studdert, C.A. and J.S. Parkinson (2005) Insights into the organization and dynamics of bacterial chemoreceptor clusters through in vivo crosslinking studies. Proc. Natl. Acad. Sci. USA 102:15623-15628.
Ames, P. and J.S. Parkinson (2006) Conformational suppression of inter-receptor signaling defects. Proc. Natl. Acad. Sci. USA 102: 9292-9297.
Zhao, J. and J.S. Parkinson (2006) Mutational analysis of the chemoreceptor-coupling domain of the Escherichia coli chemotaxis signaling kinase CheA. J. Bacteriol. 188:3299-3307.
Zhao, J. and J.S. Parkinson (2006) Cysteine-scanning analysis of the chemoreceptor-coupling domain of the Escherichia coli chemotaxis signaling kinase CheA. J. Bacteriol. 188: 4321-4330.
Burón-Barral, M., Gosink, K.K. and J.S. Parkinson (2006) Loss and gain of function mutations in the F1 HAMP region of the Escherichia coli aerotaxis transducer Aer. J. Bacteriol. 188: 3477-3486.
Gosink, K.K., Burón-Barral, M. and J.S. Parkinson (2006) Signaling interactions between the aerotaxis transducer Aer and heterologous chemoreceptors in E. coli. J. Bacteriol. 188: 3487-3493.
|
|
|
