1nnl
From Proteopedia
(New page: 200px<br /> <applet load="1nnl" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nnl, resolution 1.53Å" /> '''Crystal structure o...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1nnl.gif|left|200px]]<br /> | + | [[Image:1nnl.gif|left|200px]]<br /><applet load="1nnl" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1nnl" size=" | + | |
caption="1nnl, resolution 1.53Å" /> | caption="1nnl, resolution 1.53Å" /> | ||
'''Crystal structure of Human Phosphoserine Phosphatase'''<br /> | '''Crystal structure of Human Phosphoserine Phosphatase'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of human phosphoserine phosphatase (HPSP) in the | + | The crystal structure of human phosphoserine phosphatase (HPSP) in the open conformation has been determined at a resolution of 1.53 A. The crystals are orthorhombic, belonging to space group C222(1), with unit-cell parameters a = 49.03, b = 130.25, c = 157.29 A. The asymmetric unit contains two molecules. Phase information was derived from a multiwavelength anomalous dispersion (MAD) experiment conducted at three wavelengths using a selenomethionine-derivative crystal of HPSP. The structure was refined using CNS to a final crystallographic R value of 21.6% (R(free) = 23.4%). HPSP is a dimeric enzyme responsible for the third and final step of the l-serine biosynthesis pathway. It catalyses the Mg2+-dependent hydrolysis of l-phosphoserine. Recently, the structure of HPSP in complex with an inhibitor bound to the active site has been reported to be the open conformation of the enzyme. Here, the structure of HPSP is reported in the absence of substrate in the active site. Evidence is presented that HPSP in an uncomplexed form is in an even more open conformation than in the inhibitor complex. In this state, the enzyme is partially unfolded to allow the substrate to enter the active site. Binding of the substrate causes HPSP to shift to the closed conformation by stabilizing the partially unfolded region. In the present structure a Ca2+ ion is bound to the active site and an explanation is given why HPSP is not active when in the active site Mg2+ is replaced by a Ca2+ ion. |
==About this Structure== | ==About this Structure== | ||
| - | 1NNL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with CL and CA as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Phosphoserine_phosphatase Phosphoserine phosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.3 3.1.3.3] Full crystallographic information is available from [http:// | + | 1NNL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=CL:'>CL</scene> and <scene name='pdbligand=CA:'>CA</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Phosphoserine_phosphatase Phosphoserine phosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.3 3.1.3.3] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NNL OCA]. |
==Reference== | ==Reference== | ||
| Line 15: | Line 14: | ||
[[Category: Phosphoserine phosphatase]] | [[Category: Phosphoserine phosphatase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Collet, J | + | [[Category: Collet, J F.]] |
[[Category: Peeraer, Y.]] | [[Category: Peeraer, Y.]] | ||
[[Category: Rabijns, A.]] | [[Category: Rabijns, A.]] | ||
| - | [[Category: Ranter, C | + | [[Category: Ranter, C De.]] |
| - | [[Category: Schaftingen, E | + | [[Category: Schaftingen, E Van.]] |
[[Category: Verboven, C.]] | [[Category: Verboven, C.]] | ||
[[Category: CA]] | [[Category: CA]] | ||
| Line 28: | Line 27: | ||
[[Category: psp]] | [[Category: psp]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:07:59 2008'' |
Revision as of 12:08, 21 February 2008
|
Crystal structure of Human Phosphoserine Phosphatase
Overview
The crystal structure of human phosphoserine phosphatase (HPSP) in the open conformation has been determined at a resolution of 1.53 A. The crystals are orthorhombic, belonging to space group C222(1), with unit-cell parameters a = 49.03, b = 130.25, c = 157.29 A. The asymmetric unit contains two molecules. Phase information was derived from a multiwavelength anomalous dispersion (MAD) experiment conducted at three wavelengths using a selenomethionine-derivative crystal of HPSP. The structure was refined using CNS to a final crystallographic R value of 21.6% (R(free) = 23.4%). HPSP is a dimeric enzyme responsible for the third and final step of the l-serine biosynthesis pathway. It catalyses the Mg2+-dependent hydrolysis of l-phosphoserine. Recently, the structure of HPSP in complex with an inhibitor bound to the active site has been reported to be the open conformation of the enzyme. Here, the structure of HPSP is reported in the absence of substrate in the active site. Evidence is presented that HPSP in an uncomplexed form is in an even more open conformation than in the inhibitor complex. In this state, the enzyme is partially unfolded to allow the substrate to enter the active site. Binding of the substrate causes HPSP to shift to the closed conformation by stabilizing the partially unfolded region. In the present structure a Ca2+ ion is bound to the active site and an explanation is given why HPSP is not active when in the active site Mg2+ is replaced by a Ca2+ ion.
About this Structure
1NNL is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as Phosphoserine phosphatase, with EC number 3.1.3.3 Full crystallographic information is available from OCA.
Reference
High-resolution structure of human phosphoserine phosphatase in open conformation., Peeraer Y, Rabijns A, Verboven C, Collet JF, Van Schaftingen E, De Ranter C, Acta Crystallogr D Biol Crystallogr. 2003 Jun;59(Pt 6):971-7. Epub 2003, May 23. PMID:12777757
Page seeded by OCA on Thu Feb 21 14:07:59 2008
