User:Xuni Li/Sandbox 1

From Proteopedia

< User:Xuni Li(Difference between revisions)
Jump to: navigation, search
Current revision (18:55, 16 December 2011) (edit) (undo)
 
(36 intermediate revisions not shown.)
Line 1: Line 1:
-
<scene name='User:Xuni_Li/Sandbox_1/Scene1/1'>TextToBeDisplayed</scene>
+
<Structure load='2ch7' size='400' frame='true' align='right' caption='Cytoplasmic Domain of Thermotoga maritima receptor' scene='User:Xuni_Li/Sandbox_1/Initial/1' />
-
 
+
-
 
+
-
 
+
-
<Structure load='2ch7' size='500' frame='true' align='right' caption='Insert caption here' scene='Insert optional scene name here' />[['''Bold text'''Image:intactModelLargeText.jpg|frame|Bacterial chemotaxis receptor]]
+
One of the [[CBI Molecules]] being studied in the [http://www.umass.edu/cbi/ University of Massachusetts Amherst Chemistry-Biology Interface Program] at UMass Amherst and on display at the [http://www.molecularplayground.org/ Molecular Playground].
One of the [[CBI Molecules]] being studied in the [http://www.umass.edu/cbi/ University of Massachusetts Amherst Chemistry-Biology Interface Program] at UMass Amherst and on display at the [http://www.molecularplayground.org/ Molecular Playground].
-
Many bacteria can "smell" their surroundings and "choose" where to go. They detect molecules such as amino acids or sugars using receptors that bind these molecules and transmit a signal into the cell. This signal controls several proteins which ultimately control the direction of rotation of the motors that rotate the flagella. One direction causes the cell to continue swimming; the other direction causes the cell to tumble. When an attractant molecule binds, the receptor signals: "Things look good, keep swimming!" The opposite signal occurs when bacteria sense a repellant or less attractant molecules: "Time to tumble and try a new swimming direction."
+
=== Introduction ===
-
 
+
----
-
 
+
Bacteria use their receptors to sense the environment to change their swimming patterns. There are different kinds of [http://en.wikipedia.org/wiki/Chemoreceptor chemoreceptors] that respond to different stimuli. The figure on the right is the [http://en.wikipedia.org/wiki/Methyl-accepting_chemotaxis_protein methyl-accepting protein] of Thermotoga maritima <scene name='User:Xuni_Li/Sandbox_1/Initial/1'>receptor</scene>. Bacteria like to flee away from the repellent when high concentrations are present in the environment. CheA is a [http://en.wikipedia.org/wiki/Histidine_kinase histidine kinase] that associates with CheW, an [http://en.wikipedia.org/wiki/Adaptor_protein adaptor protein], will cause the flagella to turn clockwise and result in a tumbling motion. On the other hand, when a high concentration of attractants are present in the environment, the CheA kinase will be turned off, cause flagella to turn counterclockwise, resulting in a forward swimming pattern. <ref name="introduction">Hazelbauer, Falke and Parkinson. "Bacterial chemoreceptors: high-performance signaling in networked arrays." Biochemical Sciences, 2007, 33 (1), 9-19. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/18165013]</ref>
-
A bacterial chemotaxis receptor is an unusually long alpha-helical structure. The attractant molecule (the ligand) binds near the top of this picture and sends a signal across the membrane into the cell to control proteins that bind near the bottom. This is a model of the structure of the receptor based on experimental structures of pieces of related proteins.
+
-
 
+
-
{{Clear}}
+
-
<applet load='3atp' size='[450,338]' frame='true' align='right'
+
-
caption='Aspartate receptor ligand binding domain (1wat)' scene='User:Lynmarie_K_Thompson/Sandbox_1/Loadedfrompdb/4'/>
+
-
 
+
-
=== Ligand-binding domain ===
+
-
 
+
 +
[[Image:Receptor.png]]
-
The spinning protein (<scene name='User:Lynmarie_K_Thompson/Sandbox_1/Loadedfrompdb/4'>Initial view</scene>) ) is the ligand binding domain of the aspartate receptor with the aspartate ligand bound (LKT).
+
===Structure and Functions===
 +
----
 +
[http://en.wikipedia.org/wiki/Chemoreceptor Chemoreceptors] usually contain a periplasmic ligand binding domain, the transmembrane domain, a [http://www.ebi.ac.uk/interpro/IEntry?ac=IPR003660 HAMP domain] which is for signal conversion, and the cytoplasmic domain that contains the methylation sites, flexible bundle and protein binding sites where CheA and CheW bind.
 +
CheA is a [http://en.wikipedia.org/wiki/Histidine_kinase histidine kinase] that contains five units. The P1 domain is the site of substrate [http://en.wikipedia.org/wiki/Autophosphorylation autophosphorylation] that associates with kinase P4 domain, P2 is where phosphate transfers to CheY, another response regulator protein, from P1. P3, P4 and P5 are the dimerization, kinase and the receptor-coupling domains. The P3 domain was predicted to interact with CheW which stabilize the interface between P3 and P5. The NMR structure has shown that P5 is proximal to the CheW β barrel (residues 635-660). <ref name="structure">Park, Borbat, Gonzalez-Bonet, Bhatnagar, et al. "Reconstruction of the chemotaxis receptor-kinase assembly." Nature Structural and Molecular Biology, April 23, 2006, 13 (5), 400-407. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16622408]</ref> On the right, is the CheW with CheA P4, P5 domains (orange) <scene name='User:Xuni_Li/Sandbox_1/Initial2/1'>superimposed</scene> with CheA P3, P4, P5 (blue).
-
Molecular Playground banner: A bacterial chemotaxis receptor protein used by bacteria to "smell" their environment.
+
<scene name='User:Xuni_Li/Sandbox_1/Initial2/1'>Molecular Playground</scene>
 +
Molecular Playground banner: P4, P5 of CheA binding with CheW superimpose with P3, P4 P5 of CheA
-
{{Clear}}
+
<Structure load='Xuni1.pdb' size='300' frame='true' align='right' caption='P4, P5 of CheA binding with CheW (orange) superimpose with P3, P4, P5 of CheA (blue)' scene='User:Xuni_Li/Sandbox_1/Initial2/1' />
-
<applet load='3atp' size='[450,338]' frame='true' align='right'
+
 +
[[Image:CheA.png]]
-
=== Chemotaxis adaptor protein CheW ===
+
=== References ===
 +
----
 +
<references/>
 +
=Acknowledgement=
-
CheW is a chemotaxis adaptor protein, and part of the tertiary complex formed by the chemotaxis receptor, histidine kinase protein CheA, and CheW. As an adaptor protein, CheW mediates the interaction between the chemotaxis receptor and CheA, and is necessary for the formation of kinase active complexes. CheW has been found to bind to the P5 domain of CheA through crystallographic studies.
+
To Luis E Ramirez-Tapia his advice to develop this page.
-
At right, CheW is shown with suppression mutants (blue)that have been measured to decrease receptor binding and chemotaxis (SMJ).
+
=See Also=
 +
*[[Molecular Playground/Bacterial Chemotaxis Receptors]]
 +
*[[Molecular Playground/cytoplasmic domain of a serine chemotaxis receptor]]

Current revision

Cytoplasmic Domain of Thermotoga maritima receptor

Drag the structure with the mouse to rotate

One of the CBI Molecules being studied in the University of Massachusetts Amherst Chemistry-Biology Interface Program at UMass Amherst and on display at the Molecular Playground.

Contents

Introduction

Bacteria use their receptors to sense the environment to change their swimming patterns. There are different kinds of chemoreceptors that respond to different stimuli. The figure on the right is the methyl-accepting protein of Thermotoga maritima . Bacteria like to flee away from the repellent when high concentrations are present in the environment. CheA is a histidine kinase that associates with CheW, an adaptor protein, will cause the flagella to turn clockwise and result in a tumbling motion. On the other hand, when a high concentration of attractants are present in the environment, the CheA kinase will be turned off, cause flagella to turn counterclockwise, resulting in a forward swimming pattern. [1]

Image:Receptor.png

Structure and Functions

Chemoreceptors usually contain a periplasmic ligand binding domain, the transmembrane domain, a HAMP domain which is for signal conversion, and the cytoplasmic domain that contains the methylation sites, flexible bundle and protein binding sites where CheA and CheW bind. CheA is a histidine kinase that contains five units. The P1 domain is the site of substrate autophosphorylation that associates with kinase P4 domain, P2 is where phosphate transfers to CheY, another response regulator protein, from P1. P3, P4 and P5 are the dimerization, kinase and the receptor-coupling domains. The P3 domain was predicted to interact with CheW which stabilize the interface between P3 and P5. The NMR structure has shown that P5 is proximal to the CheW β barrel (residues 635-660). [2] On the right, is the CheW with CheA P4, P5 domains (orange) with CheA P3, P4, P5 (blue).


Molecular Playground banner: P4, P5 of CheA binding with CheW superimpose with P3, P4 P5 of CheA

P4, P5 of CheA binding with CheW (orange) superimpose with P3, P4, P5 of CheA (blue)

Drag the structure with the mouse to rotate

Image:CheA.png

References

  1. ↑ Hazelbauer, Falke and Parkinson. "Bacterial chemoreceptors: high-performance signaling in networked arrays." Biochemical Sciences, 2007, 33 (1), 9-19. PMID:[1]
  2. ↑ Park, Borbat, Gonzalez-Bonet, Bhatnagar, et al. "Reconstruction of the chemotaxis receptor-kinase assembly." Nature Structural and Molecular Biology, April 23, 2006, 13 (5), 400-407. PMID:[2]

Acknowledgement

To Luis E Ramirez-Tapia his advice to develop this page.

See Also

Proteopedia Page Contributors and Editors (what is this?)

Xuni Li

Retrieved from "http://52.214.119.220/wiki/index.php/User:Xuni_Li/Sandbox_1"
Personal tools