Signal processing within and between bacterial chemoreceptors /

Bibliographic Details
Main Author: Lai, Runzhi
Other Authors: Manson, Michael D. (Thesis advisor)
Format: Thesis eBook
Language:English
Published: [College Station, Tex.] : [Texas A&M University], [2010]
Subjects:
Online Access:Link to OAK Trust copy
Description
Abstract:The key control step in E. coli chemotaxis is regulation of CheA kinase activity by a set of four transmembrane chemoreceptors. The receptor dimers can form trimeric complexes (trimers of dimers), and these trimers can be joined by a bridge thought to consist of a CheW monomer, a CheA dimer, and a second CheW monomer. It has been proposed that trimers of receptor dimers may be joined by CheW-CheA dimer-CheW links to form an extended hexagonal lattice that may be the structural basis of the chemoreceptor patches seen in E. coli. The receptor/CheA/CheW ternary complex is a membrane-spanning allosteric enzyme whose activity is regulated by protein interactions. The study presented in this dissertation investigated intermolecular and intramolecular interactions that affect the chemotactic signal processing. I have examined functional interactions between the serine receptor Tsr and the aspartate receptor Tar using a receptor coupled in vitro phosphorylation assay. The results reveal the emergent properties of mixed receptor populations and emphasize their importance in the integrated signal processing that underlies bacterial chemotaxis. A mutational analysis of the extreme C-terminus (last fifty residues) of Tar is also presented. The results implicate the receptor C-terminus in maintenance of baseline receptor activity and in attractant-induced transmembrane signaling. They also suggest how adaptive methylation might counteract the effects of attractant binding.
Item Description:"Major Subject: Microbiology"
Title from author supplied metadata (automated record created 2010-03-12 12:08:51).
Electronic resource.
Physical Description:1 online resource.
Bibliography:Includes bibliographical references.