Sandbox20: Difference between revisions

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=The Proteins=
=The Proteins=


===RTP===
==RTP==
<Structure load='2EFW' size='300' frame='true' align='right' caption='RTP' scene='Sandbox20/2efw/3' />
<Structure load='2EFW' size='300' frame='true' align='right' caption='RTP' scene='Sandbox20/2efw/3' />


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Space
Space


===Tus===
==Tus==
<Structure load='2EWJ' size='300' frame='true' align='right' caption='Tus' scene='Sandbox20/Tus/2' />
<Structure load='2EWJ' size='300' frame='true' align='right' caption='Tus' scene='Sandbox20/Tus/2' />


This is the area for text about Tus. Original picture is <scene name='Sandbox20/Tus/2'>shown by clicking here</scene>.
This is the area for text about Tus.  


Tus binds to a conserved cytosine residue which is not base paired <scene name='Sandbox20/Tus/13'>as shown by clicking here</scene>. The interactions between residues of the Tus protein and this unpaired cytosine nucleotide are <scene name='Sandbox20/Tus/9'>shown by clicking here</scene>.
===Structural Overview===
Original picture is <scene name='Sandbox20/Tus/2'>shown by clicking here</scene>.


===DNA Binding===
Tus binds by an interaction between beta sheets (shown in green) and the major groove of DNA. This is <scene name='Sandbox20/Tus/19'>shown here</scene>
===Anti-helicase Activity===
Tus binds to a conserved cytosine residue which is not base paired <scene name='Sandbox20/Tus/13'>as shown by clicking here</scene>. The interactions between residues of the Tus protein and this unpaired cytosine nucleotide are shown in more detail <scene name='Sandbox20/Tus/9'>by clicking here</scene>.
Its ability to do this depends on the conserved glutamate residue E49.
"The crystal structure of the Tus-Ter lock shows that Glu49 of Tus makes a water-mediated hydrogen bond with the 50- phosphate of the displaced A(7) nucleotide residue, and it would thus be expected to be partially defective in formation of the locked species."
"The crystal structure of the Tus-Ter lock shows that Glu49 of Tus makes a water-mediated hydrogen bond with the 50- phosphate of the displaced A(7) nucleotide residue, and it would thus be expected to be partially defective in formation of the locked species."
This is shown <scene name='Sandbox20/Tus/18'>by clicking here</scene>
This is shown <scene name='Sandbox20/Tus/18'>by clicking here</scene>
E49K does not affect DNA binding but does affect anti-helicase activity in the ‘trapped’ complex E49 makes an indirect hydrogen bond to the phosphate of the ‘displaced’ nucleotide.