RTP and Tus: Difference between revisions

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The Replication Terminator Protein (RTP) from ''Bacillus subtilis'' is comprised of two identical dimers, each of which binds to DNA to form a homodimer. The separate dimers bind at 30 bp sequences known as the A and B termination (Ter) sites. Both of these sites have inverted 16 bp repeats which overlap at highly conserved TAT trinucleotide sequence. The structure of RTP is commonly referred to as a “winged helix” DNA binding motif and consists of a compact α helix / β-strand <scene name='RTP_and_Tus/Practice_structure/5'>secondary structure</scene> with a protruding loop (or “wing”) between the β2 and β3 strands. Both dimers of RTP interact with DNA specifically through hydrogen bonding of residues Arg 59, His 54 and Thr 55, and also through nonbonding contacts with Tyr 58. RTP also forms non-specific interactions at its N-terminus region <ref>Wilce JA. Vivian JP. Hastings AF. Otting G. Folmer RHA. Duggin IG. Wake RG. Wilce MCJ. (2001) Structure of the RTP-DNA complex and the mechanism of polar replication fork arrest. ''Nature Structural Biology'' 8: 206-210.</ref>.

The Replication Terminator Protein (RTP) from ''Bacillus subtilis'' is comprised of two identical dimers, each of which binds to DNA to form a homodimer. The separate dimers bind at 30 bp sequences known as the A and B termination (Ter) sites. Both of these sites have inverted 16 bp repeats which overlap at highly conserved TAT trinucleotide sequence. The structure of RTP is commonly referred to as a “winged helix” DNA binding motif and consists of a compact α helix / β-strand <scene name='RTP_and_Tus/Practice_structure/5'>secondary structure</scene> with a protruding loop (or “wing”) between the β2 and β3 strands. Both dimers of RTP interact with DNA specifically through hydrogen bonding of residues

<scene name='RTP_and_Tus/Practice_structure/7'>Arg 59, His 54 and Thr 55, and also through nonbonding contacts with Tyr 58</scene>. RTP also forms non-specific interactions at its N-terminus region <ref>Wilce JA. Vivian JP. Hastings AF. Otting G. Folmer RHA. Duggin IG. Wake RG. Wilce MCJ. (2001) Structure of the RTP-DNA complex and the mechanism of polar replication fork arrest. ''Nature Structural Biology'' 8: 206-210.</ref>.

The first crystal structure of RTP was determined in 1995 by Bussiere ''et al.'' (See figure above) <ref>Bussiere DE, Bastia D, White SW (1995) Crystal structure of the replication terminator protein from ''B. subtilis'' at 2.6 A. ''Cell'' 80(4): 651-60.</ref>. This analysis revealed that RTP is This first structure, which used a symmetric B Ter DNA homologue, suggested that the RTP exists as a symmetric homodimer. The idea that a symmetric protein structure could be responsible for an inherently polar mechanism has resulted in a series of proposed solutions and discoveries regarding the mechanism of replication fork arrest.

RTP and Tus: Difference between revisions

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-The Replication Terminator Protein (RTP) from ''Bacillus subtilis'' is comprised of two identical dimers, each of which binds to DNA to form a homodimer. The separate dimers bind at 30 bp sequences known as the A and B termination (Ter) sites. Both of these sites have inverted 16 bp repeats which overlap at highly conserved TAT trinucleotide sequence. The structure of RTP is commonly referred to as a “winged helix” DNA binding motif and consists of a compact α helix / β-strand <scene name='RTP_and_Tus/Practice_structure/5'>secondary structure</scene> with a protruding loop (or “wing”) between the β2 and β3 strands. Both dimers of RTP interact with DNA specifically through hydrogen bonding of residues Arg 59, His 54 and Thr 55, and also through nonbonding contacts with Tyr 58. RTP also forms non-specific interactions at its N-terminus region <ref>Wilce JA. Vivian JP. Hastings AF. Otting G. Folmer RHA. Duggin IG. Wake RG. Wilce MCJ.  (2001) Structure of the RTP-DNA complex and the mechanism of polar replication fork arrest. ''Nature Structural Biology'' 8: 206-210.</ref>.
+The Replication Terminator Protein (RTP) from ''Bacillus subtilis'' is comprised of two identical dimers, each of which binds to DNA to form a homodimer. The separate dimers bind at 30 bp sequences known as the A and B termination (Ter) sites. Both of these sites have inverted 16 bp repeats which overlap at highly conserved TAT trinucleotide sequence. The structure of RTP is commonly referred to as a “winged helix” DNA binding motif and consists of a compact α helix / β-strand <scene name='RTP_and_Tus/Practice_structure/5'>secondary structure</scene> with a protruding loop (or “wing”) between the β2 and β3 strands. Both dimers of RTP interact with DNA specifically through hydrogen bonding of residues
+<scene name='RTP_and_Tus/Practice_structure/7'>Arg 59, His 54 and Thr 55, and also through nonbonding contacts with Tyr 58</scene>. RTP also forms non-specific interactions at its N-terminus region <ref>Wilce JA. Vivian JP. Hastings AF. Otting G. Folmer RHA. Duggin IG. Wake RG. Wilce MCJ.  (2001) Structure of the RTP-DNA complex and the mechanism of polar replication fork arrest. ''Nature Structural Biology'' 8: 206-210.</ref>.
 The first crystal structure of RTP was determined in 1995 by Bussiere ''et al.'' (See figure above) <ref>Bussiere DE, Bastia D, White SW (1995) Crystal structure of the replication terminator protein from ''B. subtilis'' at 2.6 A. ''Cell'' 80(4): 651-60.</ref>. This analysis revealed that RTP is This first structure, which used a symmetric B Ter DNA homologue, suggested that the RTP exists as a symmetric homodimer. The idea that a symmetric protein structure could be responsible for an inherently polar mechanism has resulted in a series of proposed solutions and discoveries regarding the mechanism of replication fork arrest.