2fb3: Difference between revisions

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[[Image:2fb3.gif|left|200px]]<br /><applet load="2fb3" size="~~450~~" color="white" frame="true" align="right" spinBox="true"

[[Image:2fb3.gif|left|200px]]<br /><applet load="2fb3" size="350" color="white" frame="true" align="right" spinBox="true"

caption="2fb3, resolution 2.349Å" />

'''Structure of MoaA in complex with 5'-GTP'''<br />

==Overview==

The first step in molybdenum cofactor biosynthesis, the conversion of, 5'-GTP to precursor Z, an oxygen-sensitive tetrahydropyranopterin is, catalyzed by the S-adenosylmethionine (SAM)-dependent enzyme MoaA and the, accessory protein MoaC. This reaction involves the radical-initiated, intramolecular rearrangement of the guanine C8 atom. MoaA harbors an, N-terminal [4Fe-4S] cluster, which is involved in the reductive cleavage, of SAM and generates a 5'-deoxyadenosyl radical (5'-dA*), and a C-terminal, [4Fe-4S] cluster presumably involved in substrate binding and/or, activation. Biochemical studies identified residues involved in 5'-GTP, binding and the determinants of nucleotide specificity. The crystal, structure of MoaA in complex with 5'-GTP confirms the biochemical data and, provides valuable insights into the subsequent radical reaction. MoaA, binds 5'-GTP with high affinity and interacts through its C-terminal, [4Fe-4S] cluster with the guanine N1 and N2 atoms, in a yet, uncharacterized binding mode. The tightly anchored triphosphate moiety, prevents the escape of radical intermediates. This structure also, visualizes the L-Met and 5'-dA cleavage products of SAM. Rotation of the, 5'-dA ribose and/or conformational changes of the guanosine are proposed, to bring the 5'-deoxyadenosyl radical into close proximity of either the, ribose C2' and C3' or the guanine C8 carbon atoms leading to hydrogen, abstraction.

The first step in molybdenum cofactor biosynthesis, the conversion of 5'-GTP to precursor Z, an oxygen-sensitive tetrahydropyranopterin is catalyzed by the S-adenosylmethionine (SAM)-dependent enzyme MoaA and the accessory protein MoaC. This reaction involves the radical-initiated intramolecular rearrangement of the guanine C8 atom. MoaA harbors an N-terminal [4Fe-4S] cluster, which is involved in the reductive cleavage of SAM and generates a 5'-deoxyadenosyl radical (5'-dA*), and a C-terminal [4Fe-4S] cluster presumably involved in substrate binding and/or activation. Biochemical studies identified residues involved in 5'-GTP binding and the determinants of nucleotide specificity. The crystal structure of MoaA in complex with 5'-GTP confirms the biochemical data and provides valuable insights into the subsequent radical reaction. MoaA binds 5'-GTP with high affinity and interacts through its C-terminal [4Fe-4S] cluster with the guanine N1 and N2 atoms, in a yet uncharacterized binding mode. The tightly anchored triphosphate moiety prevents the escape of radical intermediates. This structure also visualizes the L-Met and 5'-dA cleavage products of SAM. Rotation of the 5'-dA ribose and/or conformational changes of the guanosine are proposed to bring the 5'-deoxyadenosyl radical into close proximity of either the ribose C2' and C3' or the guanine C8 carbon atoms leading to hydrogen abstraction.

==About this Structure==

2FB3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with SO4, MET, SF4, GTP, 5AD and POP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://~~ispc~~.weizmann.ac.il/oca-bin/ocashort?id=2FB3 OCA].

2FB3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=MET:'>MET</scene>, <scene name='pdbligand=SF4:'>SF4</scene>, <scene name='pdbligand=GTP:'>GTP</scene>, <scene name='pdbligand=5AD:'>5AD</scene> and <scene name='pdbligand=POP:'>POP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FB3 OCA].

==Reference==

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[[Category: tim barrel]]

''Page seeded by [http://~~ispc~~.weizmann.ac.il/oca OCA ] on ~~Wed Nov~~ 21 10:27:~~52 2007~~''

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:19:33 2008''

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@@ Line 1: / Line 1: @@
-[[Image:2fb3.gif|left|200px]]<br /><applet load="2fb3" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:2fb3.gif|left|200px]]<br /><applet load="2fb3" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="2fb3, resolution 2.349&Aring;" />
 '''Structure of MoaA in complex with 5'-GTP'''<br />
 ==Overview==
-The first step in molybdenum cofactor biosynthesis, the conversion of, 5'-GTP to precursor Z, an oxygen-sensitive tetrahydropyranopterin is, catalyzed by the S-adenosylmethionine (SAM)-dependent enzyme MoaA and the, accessory protein MoaC. This reaction involves the radical-initiated, intramolecular rearrangement of the guanine C8 atom. MoaA harbors an, N-terminal [4Fe-4S] cluster, which is involved in the reductive cleavage, of SAM and generates a 5'-deoxyadenosyl radical (5'-dA*), and a C-terminal, [4Fe-4S] cluster presumably involved in substrate binding and/or, activation. Biochemical studies identified residues involved in 5'-GTP, binding and the determinants of nucleotide specificity. The crystal, structure of MoaA in complex with 5'-GTP confirms the biochemical data and, provides valuable insights into the subsequent radical reaction. MoaA, binds 5'-GTP with high affinity and interacts through its C-terminal, [4Fe-4S] cluster with the guanine N1 and N2 atoms, in a yet, uncharacterized binding mode. The tightly anchored triphosphate moiety, prevents the escape of radical intermediates. This structure also, visualizes the L-Met and 5'-dA cleavage products of SAM. Rotation of the, 5'-dA ribose and/or conformational changes of the guanosine are proposed, to bring the 5'-deoxyadenosyl radical into close proximity of either the, ribose C2' and C3' or the guanine C8 carbon atoms leading to hydrogen, abstraction.
+The first step in molybdenum cofactor biosynthesis, the conversion of 5'-GTP to precursor Z, an oxygen-sensitive tetrahydropyranopterin is catalyzed by the S-adenosylmethionine (SAM)-dependent enzyme MoaA and the accessory protein MoaC. This reaction involves the radical-initiated intramolecular rearrangement of the guanine C8 atom. MoaA harbors an N-terminal [4Fe-4S] cluster, which is involved in the reductive cleavage of SAM and generates a 5'-deoxyadenosyl radical (5'-dA*), and a C-terminal [4Fe-4S] cluster presumably involved in substrate binding and/or activation. Biochemical studies identified residues involved in 5'-GTP binding and the determinants of nucleotide specificity. The crystal structure of MoaA in complex with 5'-GTP confirms the biochemical data and provides valuable insights into the subsequent radical reaction. MoaA binds 5'-GTP with high affinity and interacts through its C-terminal [4Fe-4S] cluster with the guanine N1 and N2 atoms, in a yet uncharacterized binding mode. The tightly anchored triphosphate moiety prevents the escape of radical intermediates. This structure also visualizes the L-Met and 5'-dA cleavage products of SAM. Rotation of the 5'-dA ribose and/or conformational changes of the guanosine are proposed to bring the 5'-deoxyadenosyl radical into close proximity of either the ribose C2' and C3' or the guanine C8 carbon atoms leading to hydrogen abstraction.
 ==About this Structure==
-FB3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with SO4, MET, SF4, GTP, 5AD and POP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2FB3 OCA].
+FB3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=MET:'>MET</scene>, <scene name='pdbligand=SF4:'>SF4</scene>, <scene name='pdbligand=GTP:'>GTP</scene>, <scene name='pdbligand=5AD:'>5AD</scene> and <scene name='pdbligand=POP:'>POP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FB3 OCA].
 ==Reference==
@@ Line 27: / Line 27: @@
 [[Category: tim barrel]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 10:27:52 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:19:33 2008''