1kkm
From Proteopedia
(New page: 200px<br /><applet load="1kkm" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kkm, resolution 2.80Å" /> '''L.casei HprK/P in co...) |
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| - | [[Image:1kkm.gif|left|200px]]<br /><applet load="1kkm" size=" | + | [[Image:1kkm.gif|left|200px]]<br /><applet load="1kkm" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1kkm, resolution 2.80Å" /> | caption="1kkm, resolution 2.80Å" /> | ||
'''L.casei HprK/P in complex with B.subtilis P-Ser-HPr'''<br /> | '''L.casei HprK/P in complex with B.subtilis P-Ser-HPr'''<br /> | ||
==Overview== | ==Overview== | ||
| - | HPr kinase/phosphorylase (HprK/P) controls the phosphorylation state of | + | HPr kinase/phosphorylase (HprK/P) controls the phosphorylation state of the phosphocarrier protein HPr and regulates the utilization of carbon sources by Gram-positive bacteria. It catalyzes both the ATP-dependent phosphorylation of Ser-46 of HPr and its dephosphorylation by phosphorolysis. The latter reaction uses inorganic phosphate as substrate and produces pyrophosphate. We present here two crystal structures of a complex of the catalytic domain of Lactobacillus casei HprK/P with Bacillus subtilis HPr, both at 2.8-A resolution. One of the structures was obtained in the presence of excess pyrophosphate, reversing the phosphorolysis reaction and contains serine-phosphorylated HPr. The complex has six HPr molecules bound to the hexameric kinase. Two adjacent enzyme subunits are in contact with each HPr molecule, one through its active site and the other through its C-terminal helix. In the complex with serine-phosphorylated HPr, a phosphate ion is in a position to perform a nucleophilic attack on the phosphoserine. Although the mechanism of the phosphorylation reaction resembles that of eukaryotic protein kinases, the dephosphorylation by inorganic phosphate is unique to the HprK/P family of kinases. This study provides the structure of a protein kinase in complex with its protein substrate, giving insights into the chemistry of the phospho-transfer reactions in both directions. |
==About this Structure== | ==About this Structure== | ||
| - | 1KKM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] and [http://en.wikipedia.org/wiki/Lactobacillus_casei Lactobacillus casei] with CA and PO4 as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1KKM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Bacillus_subtilis Bacillus subtilis] and [http://en.wikipedia.org/wiki/Lactobacillus_casei Lactobacillus casei] with <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=PO4:'>PO4</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KKM OCA]. |
==Reference== | ==Reference== | ||
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[[Category: protein/protein interaction]] | [[Category: protein/protein interaction]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:35:10 2008'' |
Revision as of 11:35, 21 February 2008
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L.casei HprK/P in complex with B.subtilis P-Ser-HPr
Overview
HPr kinase/phosphorylase (HprK/P) controls the phosphorylation state of the phosphocarrier protein HPr and regulates the utilization of carbon sources by Gram-positive bacteria. It catalyzes both the ATP-dependent phosphorylation of Ser-46 of HPr and its dephosphorylation by phosphorolysis. The latter reaction uses inorganic phosphate as substrate and produces pyrophosphate. We present here two crystal structures of a complex of the catalytic domain of Lactobacillus casei HprK/P with Bacillus subtilis HPr, both at 2.8-A resolution. One of the structures was obtained in the presence of excess pyrophosphate, reversing the phosphorolysis reaction and contains serine-phosphorylated HPr. The complex has six HPr molecules bound to the hexameric kinase. Two adjacent enzyme subunits are in contact with each HPr molecule, one through its active site and the other through its C-terminal helix. In the complex with serine-phosphorylated HPr, a phosphate ion is in a position to perform a nucleophilic attack on the phosphoserine. Although the mechanism of the phosphorylation reaction resembles that of eukaryotic protein kinases, the dephosphorylation by inorganic phosphate is unique to the HprK/P family of kinases. This study provides the structure of a protein kinase in complex with its protein substrate, giving insights into the chemistry of the phospho-transfer reactions in both directions.
About this Structure
1KKM is a Protein complex structure of sequences from Bacillus subtilis and Lactobacillus casei with and as ligands. Full crystallographic information is available from OCA.
Reference
X-ray structure of a bifunctional protein kinase in complex with its protein substrate HPr., Fieulaine S, Morera S, Poncet S, Mijakovic I, Galinier A, Janin J, Deutscher J, Nessler S, Proc Natl Acad Sci U S A. 2002 Oct 15;99(21):13437-41. Epub 2002 Oct 1. PMID:12359875
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