The role of protein-membrane interactions in modulation of signaling by bacterial chemoreceptors

dc.contributorManson, Michael D.
dc.creatorDraheim, Roger Russell
dc.date.accessioned2009-12-16T01:23:00Z
dc.date.accessioned2010-01-16T01:38:48Z
dc.date.accessioned2017-04-07T19:56:19Z
dc.date.available2009-12-16T01:23:00Z
dc.date.available2010-01-16T01:38:48Z
dc.date.available2017-04-07T19:56:19Z
dc.date.created2007-05
dc.date.issued2009-05-15
dc.description.abstractEnvironmental signals are sensed by membrane-spanning receptors that communicate with the cell interior. Bacterial chemoreceptors modulate the activity of the CheA kinase in response to binding of small ligands or upon interaction with substrate-bound periplasmic-binding proteins. The mechanism of signal transduction across the membrane is a displacement of the second transmembrane domain (TM2) a few angstroms toward the cytoplasm. This movement repositions a dynamic transmembrane helix relative to the plane of the cell membrane. The research presented in this dissertation investigated the contribution of TM2-membrane interactions to signaling by the aspartate chemoreceptor (Tar) of Escherichia coli. Aromatic residues that reside at the cytoplasmic polar-hydrophobic membrane interface (Trp-209 and Tyr-210) were found to play a significant role in regulating signaling by Tar. These interactions were subsequently manipulated to modulate the signaling properties of Tar. The baseline signaling state was shown to be incrementally altered by repositioning the Trp-209/Tyr-210 pair. To our knowledge, this is the first example of harnessing membrane-protein interactions to modulate the signal output of a transmembrane receptor in a controlled and predictable manner. Potential long-term applications include the use of analogous mutations to elucidate two-component signaling pathways, to engineer the signaling parameters of biosensors that incorporate chemoreceptors, and to predict the movement of dynamic transmembrane helices in silico.
dc.identifier.urihttp://hdl.handle.net/1969.1/ETD-TAMU-1336
dc.language.isoen_US
dc.subjectmembrane-protein interactions
dc.subjectreceptors
dc.subjectsignal transduction
dc.subjecttwo-component systems
dc.subjectprotein engineering
dc.titleThe role of protein-membrane interactions in modulation of signaling by bacterial chemoreceptors
dc.typeBook
dc.typeThesis

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