1z91: Difference between revisions

Line 1:

[[Image:1z91.gif|left|200px]]<br /><applet load="1z91" size="~~450~~" color="white" frame="true" align="right" spinBox="true"

[[Image:1z91.gif|left|200px]]<br /><applet load="1z91" size="350" color="white" frame="true" align="right" spinBox="true"

caption="1z91, resolution 2.50Å" />

'''x-ray crystal structure of apo-OhrRC15S in reduced form: MarR family protein'''<br />

==Overview==

The mechanisms by which Bacillus subtilis OhrR, a member of the MarR, family of transcription regulators, binds the ohrA operator and is induced, by oxidation of its lone cysteine residue by organic hydroperoxides to, sulphenic acid are unknown. Here, we describe the crystal structures of, reduced OhrR and an OhrR-ohrA operator complex. To bind DNA, OhrR employs, a chimeric winged helix-turn-helix DNA binding motif, which is composed of, extended eukaryotic-like wings, prokaryotic helix-turn-helix motifs, and, helix-helix elements. The reactivity of the peroxide-sensing cysteine is, not modulated by proximal basic residues but largely by the positive, dipole of helix alpha1. Induction originates from the alleviation of, intersubunit steric clash between the sulphenic acid moieties of the, oxidized sensor cysteines and nearby tyrosines and methionines. The, structure of the OhrR-ohrA operator complex reveals the DNA binding, mechanism of the entire MarR family and suggests a common inducer binding, pocket.

The mechanisms by which Bacillus subtilis OhrR, a member of the MarR family of transcription regulators, binds the ohrA operator and is induced by oxidation of its lone cysteine residue by organic hydroperoxides to sulphenic acid are unknown. Here, we describe the crystal structures of reduced OhrR and an OhrR-ohrA operator complex. To bind DNA, OhrR employs a chimeric winged helix-turn-helix DNA binding motif, which is composed of extended eukaryotic-like wings, prokaryotic helix-turn-helix motifs, and helix-helix elements. The reactivity of the peroxide-sensing cysteine is not modulated by proximal basic residues but largely by the positive dipole of helix alpha1. Induction originates from the alleviation of intersubunit steric clash between the sulphenic acid moieties of the oxidized sensor cysteines and nearby tyrosines and methionines. The structure of the OhrR-ohrA operator complex reveals the DNA binding mechanism of the entire MarR family and suggests a common inducer binding pocket.

==About this Structure==

1Z91 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Full crystallographic information is available from [http://~~ispc~~.weizmann.ac.il/oca-bin/ocashort?id=1Z91 OCA].

1Z91 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Z91 OCA].

==Reference==

Line 13:

[[Category: Bacillus subtilis]]

[[Category: Single protein]]

[[Category: Brennan, R.G.]]

[[Category: Brennan, R G.]]

[[Category: Fuangthong, M.]]

[[Category: Helmann, J.D.]]

[[Category: Helmann, J D.]]

[[Category: Hong, M.]]

[[Category: bacterial transcription factor]]

Line 21:

[[Category: ohrr]]

''Page seeded by [http://~~ispc~~.weizmann.ac.il/oca OCA ] on ~~Wed Nov~~ 21 07:18:~~43 2007~~''

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:13:13 2008''

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools

@@ Line 1: / Line 1: @@
-[[Image:1z91.gif|left|200px]]<br /><applet load="1z91" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1z91.gif|left|200px]]<br /><applet load="1z91" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1z91, resolution 2.50&Aring;" />
 '''x-ray crystal structure of apo-OhrRC15S in reduced form: MarR family protein'''<br />
 ==Overview==
-The mechanisms by which Bacillus subtilis OhrR, a member of the MarR, family of transcription regulators, binds the ohrA operator and is induced, by oxidation of its lone cysteine residue by organic hydroperoxides to, sulphenic acid are unknown. Here, we describe the crystal structures of, reduced OhrR and an OhrR-ohrA operator complex. To bind DNA, OhrR employs, a chimeric winged helix-turn-helix DNA binding motif, which is composed of, extended eukaryotic-like wings, prokaryotic helix-turn-helix motifs, and, helix-helix elements. The reactivity of the peroxide-sensing cysteine is, not modulated by proximal basic residues but largely by the positive, dipole of helix alpha1. Induction originates from the alleviation of, intersubunit steric clash between the sulphenic acid moieties of the, oxidized sensor cysteines and nearby tyrosines and methionines. The, structure of the OhrR-ohrA operator complex reveals the DNA binding, mechanism of the entire MarR family and suggests a common inducer binding, pocket.
+The mechanisms by which Bacillus subtilis OhrR, a member of the MarR family of transcription regulators, binds the ohrA operator and is induced by oxidation of its lone cysteine residue by organic hydroperoxides to sulphenic acid are unknown. Here, we describe the crystal structures of reduced OhrR and an OhrR-ohrA operator complex. To bind DNA, OhrR employs a chimeric winged helix-turn-helix DNA binding motif, which is composed of extended eukaryotic-like wings, prokaryotic helix-turn-helix motifs, and helix-helix elements. The reactivity of the peroxide-sensing cysteine is not modulated by proximal basic residues but largely by the positive dipole of helix alpha1. Induction originates from the alleviation of intersubunit steric clash between the sulphenic acid moieties of the oxidized sensor cysteines and nearby tyrosines and methionines. The structure of the OhrR-ohrA operator complex reveals the DNA binding mechanism of the entire MarR family and suggests a common inducer binding pocket.
 ==About this Structure==
-Z91 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1Z91 OCA].
+Z91 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Z91 OCA].
 ==Reference==
@@ Line 13: / Line 13: @@
 [[Category: Bacillus subtilis]]
 [[Category: Single protein]]
-[[Category: Brennan, R.G.]]
+[[Category: Brennan, R G.]]
 [[Category: Fuangthong, M.]]
-[[Category: Helmann, J.D.]]
+[[Category: Helmann, J D.]]
 [[Category: Hong, M.]]
 [[Category: bacterial transcription factor]]
@@ Line 21: / Line 21: @@
 [[Category: ohrr]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 07:18:43 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:13:13 2008''