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<p class="text-justify"> | <p class="text-justify"> | ||
As a proof of concept we present two receptors:<br> | As a proof of concept we present two receptors:<br> | ||
− | <b>1. </b> <a href="https://2016.igem.org/Team:Technion_Israel/Proof" | + | <b>1. </b> <a href="https://2016.igem.org/Team:Technion_Israel/Proof" >PctA-Tar </a>, |
a chimera created by replacing the Tar LBD with that of the Pseudomonas receptor PctA.<br> | a chimera created by replacing the Tar LBD with that of the Pseudomonas receptor PctA.<br> | ||
− | <b>2.</b> <a href="https://2016.igem.org/Team:Technion_Israel/Modifications/Rosetta" | + | <b>2.</b> <a href="https://2016.igem.org/Team:Technion_Israel/Modifications/Rosetta" >Histamine-Tar</a>, |
a receptor created with the help of computational design - using 'Rosetta' bioinformatics | a receptor created with the help of computational design - using 'Rosetta' bioinformatics | ||
software suite to design mutations in the Tar receptor. | software suite to design mutations in the Tar receptor. | ||
Line 312: | Line 312: | ||
Our attempts did not end here, we also present two bold attempts to fuse a ligand binding | Our attempts did not end here, we also present two bold attempts to fuse a ligand binding | ||
domain of human origin to Tar in order to induce chemotaxis towards | domain of human origin to Tar in order to induce chemotaxis towards | ||
− | <a href="https://2016.igem.org/Team:Technion_Israel/Modifications/EstoTar" | + | <a href="https://2016.igem.org/Team:Technion_Israel/Modifications/EstoTar" >Estrogen hormone</a> |
and a novel lock and key system which relies on | and a novel lock and key system which relies on | ||
<a href="https://2016.igem.org/Team:Technion_Israel/Modifications/Intein" ><b>intein proteins</b></a> | <a href="https://2016.igem.org/Team:Technion_Israel/Modifications/Intein" ><b>intein proteins</b></a> |
Revision as of 15:07, 18 October 2016
S.Tar components
S.Tar Introduction
Chemotaxis is the movement of an organism in response to an external chemical stimulus The bacterial chemotaxis system is characterized by specific responses, high sensitivity and a dynamic range (1). This system enables bacteria to sense their immediate environment and quickly adapt to changes in its chemical composition - thus fleeing from repellents or moving towards attractants. The key to this system and the first link in the chain is the bacterial chemoreceptor - a membrane protein that binds the effector and transduces the signal down the line. Despite its advantages this system is still rather limited, bacterial chemoreceptors have evolved to sense specific materials that either benefit or harm the cell in some way. The specificity of a receptor is determined by its ligand binding domain. This domain is the focus of project S.Tar.
S.Tar
The S.Tar platform offers the means to decide what substance will trigger a chemotactic response- controlled chemotaxis. The base of our project and the source of our name is the Tar chemoreceptor, one of four E. coli receptors. By changing Tar’s ligand binding domain to that of other receptors or by mutating it we show that E. coli can be engineered to respond to completely new materials.
As a proof of concept we present two receptors:
1. PctA-Tar ,
a chimera created by replacing the Tar LBD with that of the Pseudomonas receptor PctA.
2. Histamine-Tar,
a receptor created with the help of computational design - using 'Rosetta' bioinformatics
software suite to design mutations in the Tar receptor.
Our attempts did not end here, we also present two bold attempts to fuse a ligand binding
domain of human origin to Tar in order to induce chemotaxis towards
Estrogen hormone
and a novel lock and key system which relies on
intein proteins
. The purpose of these proteins is to disable chemotaxis until a specific substance “unlocks the door” - or in a more scientific way: induces
intein splicing and enables chemotaxis.
We have created non-natural chemoreceptors, by modifying Tar’s ligand binding domain.
References:
1. Bi, S. and Lai, L., 2015. Bacterial chemoreceptors and chemoeffectors. Cellular and Molecular Life Sciences, 72(4), pp.691-708.
2. BI, Shuangyu; LAI, Luhua. Bacterial chemoreceptors and chemoeffectors. Cellular and Molecular Life Sciences, 2015, 72.4: 691-708.
3. British Society for Immunology