# positions[].organizations[].parent[].label
College of Agriculture and Life Sciences

# overview
Bacteria have a limited behavioral repertoire. Their most conspicuous behavior is chemotaxis - the pursuit of molecules that are favorable to acquire and the avoidance of chemicals that are best to avoid. The simplicity of bacterial motility and chemotaxis and the amenability of the model species Escherichia coli to genetic, biochemical and physiological manipulation have facilitated rapid advances in understanding the molecular mechanisms of biological energy conversion and signal transduction.

Our laboratory studies the inputs and outputs of chemotaxis. Ligands interact with the periplasmic receptor domain of a chemotactic signal transducer that spans the cell membrane. This interaction is converted into an intracellular signal that is communicated to the flagella. Molecules can be sensed either by binding directly to a receptor or by first interacting with a periplasmic binding protein, which then interacts with a receptor.

# keywords[]
1.1 Normal Biological Development And Functioning

# educationAndTraining[].organization.label
Johns Hopkins University - (Baltimore, Maryland, United States)

# educationAndTraining[].organization.label
California Institute of Technology - (Pasadena, California, United States)

# educationAndTraining[].organization.label
Stanford University - (Stanford, California, United States)

# educationAndTraining[].organization.label
University of Colorado Boulder - (Boulder, Colorado, United States)

# publications[].label
Tryptophan operon regulation in interspecific hybrids of enteric bacteria.

# publications[].label
Signal processing times in bacterial chemotaxis.

# publications[].label
Repellent Taxis in Response to Nickel Ion Requires Neither Ni2+ Transport nor the Periplasmic NikA Binding Protein (vol 192, pg 2633, 2010)

# publications[].label
Dynamics and energetics of flagellar rotation in bacteria.

# publications[].label
Maltose chemoreceptor of Escherichia coli: interaction of maltose-binding protein and the tar signal transducer.

# publications[].label
Naturally occurring sites within the Shigella dysenteriae tryptophan operon severely limit tryptophan biosynthesis.

# publications[].label
A sensitive, versatile microfluidic assay for bacterial chemotaxis.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Investigation of bacterial chemotaxis in flow-based microfluidic devices.

# publications[].label
Chemotaxis to self-generated AI-2 promotes biofilm formation in Escherichia coli.

# publications[].label
Repellent taxis in response to nickel ion requires neither Ni2+ transport nor the periplasmic NikA binding protein.

# publications[].label
The region preceding the C-terminal NWETF pentapeptide modulates baseline activity and aspartate inhibition of Escherichia coli Tar.

# publications[].label
Tuning a bacterial chemoreceptor with protein-membrane interactions.

# publications[].label
A mechanism for simultaneous sensing of aspartate and maltose by the Tar chemoreceptor of Escherichia coli.

# publications[].label
Design and fabrication of a cellular motor driven micro fluidic system

# publications[].label
Dependence of maltose transport and chemotaxis on the amount of maltose-binding protein.

# publications[].label
Evolution of chemotactic-signal transducers in enteric bacteria.

# publications[].label
A microfluidic device for quantifying bacterial chemotaxis in stable concentration gradients.

# publications[].label
Transmembrane Signal Transduction in Bacterial Chemosensing.

# publications[].label
Mutations in tar suppress defects in maltose chemotaxis caused by specific malE mutations.

# publications[].label
CheZ phosphatase localizes to chemoreceptor patches via CheA-short.

# publications[].label
Attractant signaling by an aspartate chemoreceptor dimer with a single cytoplasmic domain.

# publications[].publisher
American Association for the Advancement of Science (AAAS)

# publications[].label
Aspartate and maltose-binding protein interact with adjacent sites in the Tar chemotactic signal transducer of Escherichia coli.

# publications[].label
Molecular architecture of chemoreceptor arrays revealed by cryoelectron tomography of Escherichia coli minicells.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Effects of Chemoreceptor Modification on the Structure of Tsr Arrays

# publications[].label
Transmembrane signaling is anything but rigid.

# publications[].label
How 34 pegs fit into 26 + 8 holes in the flagellar motor.

# publications[].label
Interspecific reconstitution of maltose transport and chemotaxis in Escherichia coli with maltose-binding protein from various enteric bacteria.

# publications[].label
Biphasic chemotaxis of Escherichia coli to the microbiota metabolite indole.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Clusters of charged residues at the C terminus of MotA and N terminus of MotB are important for function of the Escherichia coli flagellar motor.

# publications[].label
Maltose-binding protein interacts simultaneously and asymmetrically with both subunits of the Tar chemoreceptor.

# publications[].label
Conversion of Norepinephrine to 3,4-Dihdroxymandelic Acid in Escherichia coli Requires the QseBC Quorum-Sensing System and the FeaR Transcription Factor.

# publications[].label
The Norepinephrine Metabolite 3,4-Dihydroxymandelic Acid Is Produced by the Commensal Microbiota and Promotes Chemotaxis and Virulence Gene Expression in Enterohemorrhagic Escherichia coli.

# publications[].label
Chemotaxis to the quorum-sensing signal AI-2 requires the Tsr chemoreceptor and the periplasmic LsrB AI-2-binding protein.

# publications[].label
Peptide transport and chemotaxis in Escherichia coli and Salmonella typhimurium: characterization of the dipeptide permease (Dpp) and the dipeptide-binding protein.

# publications[].label
Motility protein interactions in the bacterial flagellar motor.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Reconstitution of maltose chemotaxis in Escherichia coli by addition of maltose-binding protein to calcium-treated cells of maltose regulon mutants.

# publications[].label
The Tsr chemosensory transducer of Escherichia coli assembles into the cytoplasmic membrane via a SecA-dependent process.

# publications[].label
Bacterial locomotion and signal transduction.

# publications[].label
Mot protein assembly into the bacterial flagellum: a model based on mutational analysis of the motB gene.

# publications[].label
Transposon Tn10-dependent expression of the lamB gene in Escherichia coli.

# publications[].label
Energetics of flagellar rotation in bacteria.

# publications[].label
Introduction to bacterial motility and chemotaxis.

# publications[].label
Molecular Mechanism for Attractant Signaling to DHMA by E.coli Tsr.

# publications[].label
pH Sensing in Bacillus subtilis: a New Path to a Common Goal.

# publications[].label
Mutational analysis of the transmembrane helix 2-HAMP domain connection in the Escherichia coli aspartate chemoreceptor tar.

# publications[].label
Rusty, jammed, and well-oiled hinges: Mutations affecting the interdomain region of FliG, a rotor element of the Escherichia coli flagellar motor.

# publications[].label
Chimeric chemoreceptors in Escherichia coli: signaling properties of Tar-Tap and Tap-Tar hybrids.

# publications[].label
A mutational wrench in the HAMP gearbox.

# publications[].label
Protein domains and residues involved in the CheZ/CheAS interaction.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Allele-specific suppression as a tool to study protein-protein interactions in bacteria.

# publications[].label
Chemotaxis of Escherichia coli to norepinephrine (NE) requires conversion of NE to 3,4-dihydroxymandelic acid.

# publications[].label
Tryptophan residues flanking the second transmembrane helix (TM2) set the signaling state of the Tar chemoreceptor.

# publications[].label
TEM Anaysis of Chemoreceptor Arrays in Native Membranes of E. coli

# publications[].label
Design and fabrication of a cellular motor driven micro fluidic system

# publications[].label
One Basic Blueprint, Many Different Motors.

# publications[].label
Sequence of the mglB gene from Escherichia coli K12: comparison of wild-type and mutant galactose chemoreceptors.

# publications[].label
The Diversity of Bacterial Chemosensing.

# publications[].label
Flow-based microfluidic device for quantifying bacterial chemotaxis in stable, competing gradients.

# publications[].label
Comparison of sequences from the malB regions of Salmonella typhimurium and Enterobacter aerogenes with Escherichia coli K12: a potential new regulatory site in the interoperonic region.

# publications[].label
Listening to new signals with old ears: Sensing and recognition of the quorum sensing signal AI-2 by the TSR chemoreceptor

# publications[].label
Cryoelectron tomography reveals the sequential assembly of bacterial flagella in Borrelia burgdorferi.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Microfluidic techniques for the analysis of bacterial chemotaxis.

# publications[].label
Peptide chemotaxis in E. coli involves the Tap signal transducer and the dipeptide permease.

# publications[].label
The residue composition of the aromatic anchor of the second transmembrane helix determines the signaling properties of the aspartate/maltose chemoreceptor Tar of Escherichia coli.

# publications[].label
Mutationally altered signal output in the Nart (NarX-Tar) hybrid chemoreceptor.

# publications[].label
Mutations in motB suppressible by changes in stator or rotor components of the bacterial flagellar motor.

# publications[].label
Not too loose, not too tight--just right. Biphasic control of the Tsr HAMP domain.

# publications[].label
Maltose-binding protein containing an interdomain disulfide bridge confers a dominant-negative phenotype for transport and chemotaxis.

# publications[].label
Maltose chemotaxis involves residues in the N-terminal and C-terminal domains on the same face of maltose-binding protein.

# publications[].label
The tie that binds the dynamic duo: the connector between AS1 and AS2 in the HAMP domain of the Escherichia coli Tsr chemoreceptor.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
The dipeptide permease of Escherichia coli closely resembles other bacterial transport systems and shows growth-phase-dependent expression.

# publications[].label
Howard Berg's Random Walk through Biology.

# publications[].label
Extragenic suppression of motA missense mutations of Escherichia coli.

# publications[].label
A protonmotive force drives bacterial flagella.

# publications[].publisher
Proceedings of the National Academy of Sciences

# publications[].label
Residues at the cytoplasmic end of transmembrane helix 2 determine the signal output of the TarEc chemoreceptor.

# publications[].label
The Escherichia coli MotAB proton channel unplugged.

# publications[].label
A NarX-Tar chimera mediates repellent chemotaxis to nitrate and nitrite.

# researcherOn[].awardedBy.label
National Science Foundation - (Arlington, Virginia, United States)

# streetAddress
Texas A&M University; Biology; 3258 TAMU

# organizations[]
College of Agriculture and Life Sciences

# schools[]
College of Agriculture and Life Sciences

# etdChairOf[].label
Ward, Scott Michael (2005-08). Comparison of the mechanism of transmembrane signaling in bacterial chemoreceptors and sensor kinases. Doctoral Dissertation.

# etdChairOf[].label
Draheim, Roger Russell (2007-05). The role of protein-membrane interactions in modulation of signaling by bacterial chemoreceptors. Doctoral Dissertation.

# etdChairOf[].label
Bormans, Arjan Frank (2005-12). Intradimer and interdimer methylation response by bacterial chemoreceptors to attractant stimulus. Doctoral Dissertation.

# etdChairOf[].label
Jani, Sneha Jagdish (2017-05). Chemotaxis toward Autoinducer-2 and Its Role in Biofilm Development in Escherichia coli. Doctoral Dissertation.

# etdChairOf[].label
Wright, Gus Alan (2009-08). The Role of the TM2-HAMP Junction in Control of the Signaling State of the Aspartate Chemoreceptor of E. coli. Doctoral Dissertation.

# etdChairOf[].label
Adase, Christopher A. 1981- (2012-12). The C-Terminus of Transmembrane Helix 2 (TM2) of the Escherichia coli Tar Chemorecptor Determines Signal Output and Ligand Sensitivity. Doctoral Dissertation.

# etdChairOf[].label
Hosking, Edan Robert (2003-05). Assembly of the Mot protein complex into the Escherichia coli flagellar motor. Doctoral Dissertation.

# etdChairOf[].label
Cantwell, Brian Jay (2006-12). Localization of the phosphatase CheZ to the chemoreceptor patch of Escherichia coli. Doctoral Dissertation.

# etdChairOf[].label
Lai, Runzhi (2007-05). Signal processing within and between bacterial chemoreceptors. Doctoral Dissertation.

# etdChairOf[].label
Seely, Andrew Loran (2017-08). An Analysis of the Tsr-LsrB Interaction During Autoinducer-2 Chemotaxis In Escherichia coli. Doctoral Dissertation.