User:Nathan Harris/Tus: Difference between revisions
No edit summary |
No edit summary |
||
Line 14: | Line 14: | ||
Tus constitutes 308 amino acid residues and a mass of approximately 36 kDa. The structural components of Tus have been elucidated through crystal structures of Tus bound to a fragment of ''TerA''. Tus exhibits a unique binding motif to Ter sites previously undescribed from any known protein-DNA interactions. | Tus constitutes 308 amino acid residues and a mass of approximately 36 kDa. The structural components of Tus have been elucidated through crystal structures of Tus bound to a fragment of ''TerA''. Tus exhibits a unique binding motif to Ter sites previously undescribed from any known protein-DNA interactions. | ||
Tus is divided into an amino and carboxy domain distinguished by two alpha helical regions and central β sheets combining to encompass a large central basic cleft. The interdomain region consists of anti-parallel β strands and an extended L4 loop which connect the amino and carboxy domains. Within this interdomain region, the βF, βG, βH and βI strands are responsible for specific and non-specific recognition of ''Ter''. | Tus is divided into an <scene name='User:Nathan_Harris/Tus/Amino_domian/1'>amino domain</scene> and carboxy domain distinguished by two alpha helical regions and central β sheets combining to encompass a large central basic cleft. The interdomain region consists of anti-parallel β strands and an extended L4 loop which connect the amino and carboxy domains. Within this interdomain region, the βF, βG, βH and βI strands are responsible for specific and non-specific recognition of ''Ter''. | ||
The amino domain consists of three amphipathic alpha helices forming an anti-parallel bundle roughly parallel to ''Ter'', a sandwich of anti-parallel β sheets and three loops. The major groove and minor groove are clamped by two alpha helices (αIV and αV) which also contribute to the hydrophobic core of the protein. Within the β sandwich, βCADKE contacts the alpha helical region, whereas βLFIJ is associated with DNA binding. Furthermore, the extended L4 loop is also involved in contacts to the minor groove. | The amino domain consists of three amphipathic alpha helices forming an anti-parallel bundle roughly parallel to ''Ter'', a sandwich of anti-parallel β sheets and three loops. The major groove and minor groove are clamped by two alpha helices (αIV and αV) which also contribute to the hydrophobic core of the protein. Within the β sandwich, βCADKE contacts the alpha helical region, whereas βLFIJ is associated with DNA binding. Furthermore, the extended L4 loop is also involved in contacts to the minor groove. | ||
The carboxy domain consists of a hydrophobic core stabilised by alpha helices and β strands (βGHNO). The L3 loop is responsible for connecting helices αVI and αVII and also contacts the minor groove of DNA. | The carboxy domain consists of a hydrophobic core stabilised by alpha helices and β strands (βGHNO). The L3 loop is responsible for connecting helices αVI and αVII and also contacts the minor groove of DNA. |