Sandbox20: Difference between revisions
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[[Image:Tus 1 labelled helices.jpg | thumb | upright=1.5| left| Secondary structures of the Tus protein.]] | [[Image:Tus 1 labelled helices.jpg | thumb | upright=1.5| left| Secondary structures of the Tus protein.]] | ||
The structure of the Tus protein in complex with TerA revealed a previously undescribed backbone conformation (<scene name='Sandbox20/Tus/2'>original model</scene>.) <ref>pdb: 8857533</ref>. It can be divided into the major amino and carboxy domains, in which the α-helical regions of each are spanned by a central β-sandwich which makes contact with the DNA duplex. Three helices within the amino domain (αI αII, αIII) form an antiparallel bundle aligned parallel to the DNA (blue, left). Another two helices (αIV, αV) clamp the DNA phosphate backbone at the non-permissive end. This generates the cytosine-specific pocket with the crucial residues for anti-helicase activity. The main DNA-binding domain however is the exposed side of the double β sheet layer which provides several base-specific interactions. This lies within the major groove and causes a conformational change in the DNA involving a deepening of the major groove, and an expansion of the minor one (green, left). | The structure of the Tus protein in complex with TerA revealed a previously undescribed backbone conformation (<scene name='Sandbox20/Tus/2'>original model</scene>.) <ref>pdb: 8857533</ref>. It can be divided into the major amino and carboxy domains, in which the α-helical regions of each are spanned by a central β-sandwich which makes contact with the DNA duplex. Three helices within the amino domain (αI αII, αIII) form an antiparallel bundle aligned parallel to the DNA (blue, left). Another two helices (αIV, αV) clamp the DNA phosphate backbone at the non-permissive end. This generates the cytosine-specific pocket with the crucial residues for anti-helicase activity. The main DNA-binding domain, however, is the exposed side of the double β sheet layer which provides several base-specific interactions. This lies within the major groove and causes a conformational change in the DNA involving a deepening of the major groove, and an expansion of the minor one (green, left). | ||
===DNA Binding=== | ===DNA Binding=== | ||