2nv2
From Proteopedia
(New page: 200px<br /><applet load="2nv2" size="450" color="white" frame="true" align="right" spinBox="true" caption="2nv2, resolution 2.12Å" /> '''Structure of the PLP...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:2nv2.gif|left|200px]]<br /><applet load="2nv2" size=" | + | [[Image:2nv2.gif|left|200px]]<br /><applet load="2nv2" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2nv2, resolution 2.12Å" /> | caption="2nv2, resolution 2.12Å" /> | ||
'''Structure of the PLP synthase complex Pdx1/2 (YaaD/E) from Bacillus subtilis'''<br /> | '''Structure of the PLP synthase complex Pdx1/2 (YaaD/E) from Bacillus subtilis'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Vitamin B6 is an essential metabolic cofactor that has more functions in | + | Vitamin B6 is an essential metabolic cofactor that has more functions in humans than any other single nutrient. Its de novo biosynthesis occurs through two mutually exclusive pathways that are absent in animals. The predominant pathway found in most prokaryotes, fungi, and plants has only recently been discovered. It is distinguished by a glutamine amidotransferase, which is remarkable in that it alone can synthesize the cofactor form, pyridoxal 5'-phosphate (PLP), directly from a triose and a pentose saccharide and glutamine. Here we report the 3D structure of the PLP synthase complex with substrate glutamine bound as well as those of the individual synthase and glutaminase subunits Pdx1 and Pdx2, respectively. The complex is made up of 24 protein units assembled like a cogwheel, a dodecameric Pdx1 to which 12 Pdx2 subunits attach. In contrast to the architecture of previously determined glutamine amidotransferases, macromolecular assembly is directed by an N-terminal alpha-helix on the synthase. Interaction with the synthase subunit leads to glutaminase activation, resulting in formation of an oxyanion hole, a prerequisite for catalysis. Mutagenesis permitted identification of the remote glutaminase and synthase catalytic centers and led us to propose a mechanism whereby ammonia shuttles between these active sites through a methionine-rich hydrophobic tunnel. |
==About this Structure== | ==About this Structure== | ||
| - | 2NV2 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with CL, EDO and GLN as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 2NV2 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] with <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=EDO:'>EDO</scene> and <scene name='pdbligand=GLN:'>GLN</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2NV2 OCA]. |
==Reference== | ==Reference== | ||
| Line 23: | Line 23: | ||
[[Category: plp synthase complex]] | [[Category: plp synthase complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:11:18 2008'' |
Revision as of 16:11, 21 February 2008
|
Structure of the PLP synthase complex Pdx1/2 (YaaD/E) from Bacillus subtilis
Overview
Vitamin B6 is an essential metabolic cofactor that has more functions in humans than any other single nutrient. Its de novo biosynthesis occurs through two mutually exclusive pathways that are absent in animals. The predominant pathway found in most prokaryotes, fungi, and plants has only recently been discovered. It is distinguished by a glutamine amidotransferase, which is remarkable in that it alone can synthesize the cofactor form, pyridoxal 5'-phosphate (PLP), directly from a triose and a pentose saccharide and glutamine. Here we report the 3D structure of the PLP synthase complex with substrate glutamine bound as well as those of the individual synthase and glutaminase subunits Pdx1 and Pdx2, respectively. The complex is made up of 24 protein units assembled like a cogwheel, a dodecameric Pdx1 to which 12 Pdx2 subunits attach. In contrast to the architecture of previously determined glutamine amidotransferases, macromolecular assembly is directed by an N-terminal alpha-helix on the synthase. Interaction with the synthase subunit leads to glutaminase activation, resulting in formation of an oxyanion hole, a prerequisite for catalysis. Mutagenesis permitted identification of the remote glutaminase and synthase catalytic centers and led us to propose a mechanism whereby ammonia shuttles between these active sites through a methionine-rich hydrophobic tunnel.
About this Structure
2NV2 is a Protein complex structure of sequences from Bacillus subtilis with , and as ligands. Full crystallographic information is available from OCA.
Reference
Structure of a bacterial pyridoxal 5'-phosphate synthase complex., Strohmeier M, Raschle T, Mazurkiewicz J, Rippe K, Sinning I, Fitzpatrick TB, Tews I, Proc Natl Acad Sci U S A. 2006 Dec 19;103(51):19284-9. Epub 2006 Dec 11. PMID:17159152
Page seeded by OCA on Thu Feb 21 18:11:18 2008
