Team:Kyoto/Secretion/Project

From 2012.igem.org

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(Introduction)
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=='''Introduction'''==
=='''Introduction'''==
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==How We iGEMer Extract Proteins from Escherichia.coli?==
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===How We iGEMer Extract Proteins from Escherichia.coli?===
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===Lysis is ...?===
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====Lysis is ...?====
<p>Until now, we use only cell death as secretion pathway. It is true that protein in the E.coli emerges when an E.coli die and lysed. However, it is not smart that whenever we need protein synthesized by E.coli we have to kill the E.coli.</p>
<p>Until now, we use only cell death as secretion pathway. It is true that protein in the E.coli emerges when an E.coli die and lysed. However, it is not smart that whenever we need protein synthesized by E.coli we have to kill the E.coli.</p>
<p>When many many E.coli are exist on environment, it is no problem that we kill a bit E.coli, but when a little E.coli are exist, E.coli might be annihilated if we force them die through introducing lysis genes. When there are little nutriment in the system's environment, E.coli could not breed and if there are nutriment in the system's environment, E.coli consume that and we have to supply nutriment constantly. In order to meintain your system with E.coli, you must grow E.coli genetically engineered by yourself. We want to save our E.coli when we extract protein, but how ?</p>
<p>When many many E.coli are exist on environment, it is no problem that we kill a bit E.coli, but when a little E.coli are exist, E.coli might be annihilated if we force them die through introducing lysis genes. When there are little nutriment in the system's environment, E.coli could not breed and if there are nutriment in the system's environment, E.coli consume that and we have to supply nutriment constantly. In order to meintain your system with E.coli, you must grow E.coli genetically engineered by yourself. We want to save our E.coli when we extract protein, but how ?</p>
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===What is TAT Secretion System?===
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====What is TAT Secretion System?====
<p>The Twin Arginate Translocation pathway(TAT) is secretion system and E.coli have this system originally. Proteins named tatA, tatB, tatC, and tatD make holes on inner memblane and recognize a signal. Tat ABCD recognize torA signal peptide and then they let protein (with torA) pass. In addition, protein that has passed through TAT pathway, cut off the torA signal. Proteins which secreted by this system have no tag that obstruct activation of the protein.</p>
<p>The Twin Arginate Translocation pathway(TAT) is secretion system and E.coli have this system originally. Proteins named tatA, tatB, tatC, and tatD make holes on inner memblane and recognize a signal. Tat ABCD recognize torA signal peptide and then they let protein (with torA) pass. In addition, protein that has passed through TAT pathway, cut off the torA signal. Proteins which secreted by this system have no tag that obstruct activation of the protein.</p>
<p>TAT secretion system make holes on inner memblane. It means protein with torA tag goes to only periplasmic space, not outside of outer memblane. We want to extract proteins from E.coli, not to translocate it into periplasm. We must make a hole on outer memblane in order to extract protein in periplasm.</p>
<p>TAT secretion system make holes on inner memblane. It means protein with torA tag goes to only periplasmic space, not outside of outer memblane. We want to extract proteins from E.coli, not to translocate it into periplasm. We must make a hole on outer memblane in order to extract protein in periplasm.</p>

Revision as of 11:46, 19 September 2012

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Contents

Introduction

How We iGEMer Extract Proteins from Escherichia.coli?

Lysis is ...?

Until now, we use only cell death as secretion pathway. It is true that protein in the E.coli emerges when an E.coli die and lysed. However, it is not smart that whenever we need protein synthesized by E.coli we have to kill the E.coli.

When many many E.coli are exist on environment, it is no problem that we kill a bit E.coli, but when a little E.coli are exist, E.coli might be annihilated if we force them die through introducing lysis genes. When there are little nutriment in the system's environment, E.coli could not breed and if there are nutriment in the system's environment, E.coli consume that and we have to supply nutriment constantly. In order to meintain your system with E.coli, you must grow E.coli genetically engineered by yourself. We want to save our E.coli when we extract protein, but how ?

What is TAT Secretion System?

The Twin Arginate Translocation pathway(TAT) is secretion system and E.coli have this system originally. Proteins named tatA, tatB, tatC, and tatD make holes on inner memblane and recognize a signal. Tat ABCD recognize torA signal peptide and then they let protein (with torA) pass. In addition, protein that has passed through TAT pathway, cut off the torA signal. Proteins which secreted by this system have no tag that obstruct activation of the protein.

TAT secretion system make holes on inner memblane. It means protein with torA tag goes to only periplasmic space, not outside of outer memblane. We want to extract proteins from E.coli, not to translocate it into periplasm. We must make a hole on outer memblane in order to extract protein in periplasm.

From Periplasm to Outside

TatABCD make pathway from inside of inner memblane to periplasm. Kil makes holes on outer memblane. Needless to say, outer memblane is essential for E.coli to survive. In other words, overexpression of Kil cause cell death. In this reason, we must try to find suitable amount of expression.

Detail of Our Secretion System

We constructed a wonderful secretion system contains tatABCD, Kil, and an other gene. PspA is the gene that E.coli have originally and this gene expressed when their inner memblane is dameged. PspA meintains H+ concentration gradient between periplasm and cytoplasm.

The reason why we need pspA in order to achieve our goal is that </div> </div> </div>