"
Team:Imperial College London/M3/DamMethylation
From 2009.igem.org
(→Dam methylation) |
(→Dam methylation) |
||
| Line 11: | Line 11: | ||
To protect against DNA destruction due to basal levels of restriction enzyme production, we have made use of the native E. coli Dam methylase protection system. <br> | To protect against DNA destruction due to basal levels of restriction enzyme production, we have made use of the native E. coli Dam methylase protection system. <br> | ||
| + | [[Image:II09_Dpn_meth.jpg| right]] | ||
<br> | <br> | ||
Dam methylases recognises the sequence GATC and methylates the Adenine base. This prevents the restriction enzymes from recognising the sequence and cleaving it. Therefore, only high levels of restriction enzyme (ie. after thermal triggering) will cleave the DNA. <br> | Dam methylases recognises the sequence GATC and methylates the Adenine base. This prevents the restriction enzymes from recognising the sequence and cleaving it. Therefore, only high levels of restriction enzyme (ie. after thermal triggering) will cleave the DNA. <br> | ||
| Line 19: | Line 20: | ||
The methylase protection system has been used with its native promoter to prevent basal levels of restriction enzyme expression from killing the cell. The use of a native promoter shows the highly sensitive balance that exist between restriction enzymes and methylases. | The methylase protection system has been used with its native promoter to prevent basal levels of restriction enzyme expression from killing the cell. The use of a native promoter shows the highly sensitive balance that exist between restriction enzymes and methylases. | ||
| - | + | <!-- | |
<html><a href="https://2009.igem.org/Team:Imperial_College_London/Dam"><img style="vertical-align:bottom;" width=90px align="left" src="http://i691.photobucket.com/albums/vv271/dk806/II09_Learnmore.png"></a></html><br><br> about the Dam methylation Defense Mechanism | <html><a href="https://2009.igem.org/Team:Imperial_College_London/Dam"><img style="vertical-align:bottom;" width=90px align="left" src="http://i691.photobucket.com/albums/vv271/dk806/II09_Learnmore.png"></a></html><br><br> about the Dam methylation Defense Mechanism | ||
| Line 27: | Line 28: | ||
<html><center><a href="https://2009.igem.org/Team:Imperial_College_London/M2"><img width=150px src="https://static.igem.org/mediawiki/2009/1/11/II09_M3ArrowLeft.png"></a><a href="https://2009.igem.org/Team:Imperial_College_London/Temporal_Control"><img width=150px src="https://static.igem.org/mediawiki/2009/b/bf/II09_M3_ArrowRight.png"></a></center> | <html><center><a href="https://2009.igem.org/Team:Imperial_College_London/M2"><img width=150px src="https://static.igem.org/mediawiki/2009/1/11/II09_M3ArrowLeft.png"></a><a href="https://2009.igem.org/Team:Imperial_College_London/Temporal_Control"><img width=150px src="https://static.igem.org/mediawiki/2009/b/bf/II09_M3_ArrowRight.png"></a></center> | ||
</html> | </html> | ||
| - | + | --> | |
{{Imperial/09/Division}} | {{Imperial/09/Division}} | ||
Revision as of 01:00, 7 October 2009
- Overview
- Restriction Enzymes
- Dam Methylation
- Thermoinduction
Module 3: Genome Deletion Overview
Dam methylation
To protect against DNA destruction due to basal levels of restriction enzyme production, we have made use of the native E. coli Dam methylase protection system.
Dam methylases recognises the sequence GATC and methylates the Adenine base. This prevents the restriction enzymes from recognising the sequence and cleaving it. Therefore, only high levels of restriction enzyme (ie. after thermal triggering) will cleave the DNA.
There is an asymmetry between restriction enzymes and methylases. Restriction enzymes can cause just one cleavage that kills the cell. However, to protct the cell, methylases need to methylate all the recognition sites.
The methylase protection system has been used with its native promoter to prevent basal levels of restriction enzyme expression from killing the cell. The use of a native promoter shows the highly sensitive balance that exist between restriction enzymes and methylases.
