Team:EPF-Lausanne/Our Project/TetR mutants/MITOMI data

From 2011.igem.org

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(In Vitro Characterization)
 
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===In Vitro Characterization===
===In Vitro Characterization===
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Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR V36F mutant. To do so, we first designed and generated the library of double stranded DNA sequences that cover all possible single base substitutions within the TetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the Tet operator sequence (expressed as a PWM).
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the wild type TetR. To do so, we first designed and generated the library of double-stranded DNA sequences that cover all possible single base substitutions within the TetO operator sequence. Based on that library we measured the dissociation constants of the mutant to all the tetO-like sequences of the library. Then, we determined the specificity of the mutant to the Tet operator sequence, expressed as a position-weight matrix (PWM).
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The WebLogo we obtained:
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The enoLOGO we obtained for the wild-type is:
[[File:EPFL2011_WTTetR_WebLogo.png|700px]]
[[File:EPFL2011_WTTetR_WebLogo.png|700px]]
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'''WebLogo reference:'''<p>
+
'''enoLOGO reference:'''<p>
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
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Each row represents the changes in binding energy,  ΔΔG (kcal/mol), compared to the reference sequence upon the substitution of the indicated nucleotide at a certain position within the target DNA element. Values are indicated in kcal/mol.
Each row represents the changes in binding energy,  ΔΔG (kcal/mol), compared to the reference sequence upon the substitution of the indicated nucleotide at a certain position within the target DNA element. Values are indicated in kcal/mol.
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We compared the measured DNA binding affinities of the V36F mutant to the affinities obtained for the  wt-TetR and found that the V36F mutant interacts with the TetO as strong as the wild-type variant.
 
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[[File:EPFL2011_Scatter_plot_kd_wt_VF36.png|600px]]
 
=Mutant TetRs=
=Mutant TetRs=
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===In Vitro Characterization===
===In Vitro Characterization===
-
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR V36F mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR V36F mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).
-
The WebLogo we obtained for the V36F mutant:
+
The enoLOGO we obtained for the V36F mutant:
[[File:EPFL2011_MITOMI_WebLogo_V36F.png|700px]]
[[File:EPFL2011_MITOMI_WebLogo_V36F.png|700px]]
-
'''WebLogo reference:'''<p>
+
'''enoLOGO reference:'''<p>
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
Line 147: Line 143:
===In Vitro Characterization===
===In Vitro Characterization===
-
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR E37A  W43S T141A  mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR E37A  W43S T141A  mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).  
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The WebLogo we obtained for the E37A W43S T141A mutant:
+
The measured DNA binding affinities of the E37A W43S T141A mutant show that these mutations alter the sequence recognition, while the symmetry and the spacer affinities are conserved.
 +
 
 +
 
 +
The enoLOGO we obtained for the E37A W43S T141A mutant:
[[File:EPFL2011_WebLogo_EA37WS43TA41.png|700px]]
[[File:EPFL2011_WebLogo_EA37WS43TA41.png|700px]]
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'''Reference:'''<p>
+
'''enoLOGO reference:'''<p>
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
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===In Vitro Characterization===
===In Vitro Characterization===
-
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR P39K mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR P39K mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM).
-
The WebLogo we obtained for the P39K mutant:
+
 
 +
The enoLOGO we obtained for the P39K mutant:
[[File:EPFL2011_P39K_WebLogo.png|700px]]
[[File:EPFL2011_P39K_WebLogo.png|700px]]
 +
 +
The strong difference of the binding affinities between the P39K mutant and the wtTetR, might be due to the altered recognition of the P39K. This mutant was shown to have  a new recognition specificity for the tetO-4C operator in [http://www.sciencedirect.com/science/article/pii/S0022283697915400 Helbl et al, 1998]. 
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enoLOGOS: a versatile web tool for energy normalized sequence logos.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
Nucleic Acids Res. 2005 Jul 1;33:W389-92.</p>
Nucleic Acids Res. 2005 Jul 1;33:W389-92.</p>
 +
Helbl, V., and Hillen, W. (1998). Stepwise selection of TetR variants recognizing tet operator 4C with high affinity and specificity. J Mol Biol 276, 313-318.
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 +
===Position Weight Matrix===
===Position Weight Matrix===
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===In Vitro Characterization===
===In Vitro Characterization===
-
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR Y42F mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM). For the Y42F mutant we observed the decrease of the specificity compared to the wild-type tetR sequence.
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR Y42F mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM). For the Y42F mutant we observed the decrease of the specificity compared to the wild-type tetR sequence.
-
The WebLogo we obtained for the Y42F mutant:
+
The enoLOGO we obtained for the Y42F mutant:
[[File:EPFL2011_WebLogo_Y42F.png|700px]]
[[File:EPFL2011_WebLogo_Y42F.png|700px]]
-
'''Reference:'''<p>
+
The measured binding affinities show no symmetry conservation and the contribution of the outer bases equals that of the inner.  These experiment will have to be repeated in order to get a clearer idea of the binding affinities.
 +
 
 +
 
 +
'''enoLOGO reference:'''<p>
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
enoLOGOS: a versatile web tool for energy normalized sequence logos.
Nucleic Acids Res. 2005 Jul 1;33:W389-92.</p>
Nucleic Acids Res. 2005 Jul 1;33:W389-92.</p>
-
 
+
===Position Weight Matrix===
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====Position Weight Matrix====
+
{| {{table}}
{| {{table}}
| align="center" style="background:#f0f0f0;"|'''PO'''
| align="center" style="background:#f0f0f0;"|'''PO'''
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===In Vitro Characterization===
===In Vitro Characterization===
-
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Our_Project/TetR_mutants/MITOMI_data">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR P39Q Y42M mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM). For the P39Q Y42M mutant we observed the decrease of the specificity compared to the wild-type tetR sequence.
+
Using the <html> <a href="https://2011.igem.org/Team:EPF-Lausanne/Tools/MITOMI">MITOMI</a></html> technique we determined the DNA binding landscape of the TetR P39Q Y42M mutant. To do so, first we designed and generated the library of double stranded DNA sequences that cover all possible single base substitution within the tetO operator sequence. Based on that library we measured the dissociation constants of the mutant to variable tetO-like sequences and determined the specificity of the mutant to the tet operator sequence (expressed as a PWM). For the P39Q Y42M mutant we observed the decrease of the specificity compared to the wild-type tetR sequence.
-
The WebLogo we obtained for the P39Q Y42M mutant:
+
The enoLOGO we obtained for the P39Q Y42M mutant:
[[File:EPFL2011_P39QY42M_WebLogo.png|700px]]
[[File:EPFL2011_P39QY42M_WebLogo.png|700px]]
 +
'''enoLOGO reference:'''<p>
 +
Workman CT, Yin Y, Corcoran DL, Ideker T, Stormo GD, Benos PV.
 +
enoLOGOS: a versatile web tool for energy normalized sequence logos.
 +
Nucleic Acids Res. 2005 Jul 1;33:W389-92.</p>
-
====Position Weight Matrix====
+
===Position Weight Matrix===
{| {{table}}
{| {{table}}
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| 17||0.0634094||0||0.455977||0.0582705
| 17||0.0634094||0||0.455977||0.0582705
|}
|}
 +
 +
Each row represents the changes in binding energy,  ΔΔG, compared to the reference sequence upon the substitution to the indicated nucleotide at certain position within the target DNA element. Values are indicated in kcal/mol.
Each row represents the changes in binding energy,  ΔΔG, compared to the reference sequence upon the substitution to the indicated nucleotide at certain position within the target DNA element. Values are indicated in kcal/mol.

Latest revision as of 21:49, 26 October 2011