1jpn
From Proteopedia
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| - | [[Image:1jpn.gif|left|200px]] | + | [[Image:1jpn.gif|left|200px]] |
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| - | '''GMPPNP Complex of SRP GTPase NG Domain''' | + | {{Structure |
| + | |PDB= 1jpn |SIZE=350|CAPTION= <scene name='initialview01'>1jpn</scene>, resolution 1.90Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=GNP:PHOSPHOAMINOPHOSPHONIC+ACID-GUANYLATE+ESTER'>GNP</scene> and <scene name='pdbligand=ACY:ACETIC ACID'>ACY</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''GMPPNP Complex of SRP GTPase NG Domain''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1JPN is a [ | + | 1JPN is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JPN OCA]. |
==Reference== | ==Reference== | ||
| - | The conformation of bound GMPPNP suggests a mechanism for gating the active site of the SRP GTPase., Padmanabhan S, Freymann DM, Structure. 2001 Sep;9(9):859-67. PMID:[http:// | + | The conformation of bound GMPPNP suggests a mechanism for gating the active site of the SRP GTPase., Padmanabhan S, Freymann DM, Structure. 2001 Sep;9(9):859-67. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11566135 11566135] |
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Thermus aquaticus]] | [[Category: Thermus aquaticus]] | ||
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[[Category: srp54]] | [[Category: srp54]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 12:06:40 2008'' |
Revision as of 10:06, 20 March 2008
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| , resolution 1.90Å | |||||||
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| Ligands: | , and | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
GMPPNP Complex of SRP GTPase NG Domain
Overview
BACKGROUND: The signal recognition particle (SRP) is a phylogenetically conserved ribonucleoprotein that mediates cotranslational targeting of secreted and membrane proteins to the membrane. Targeting is regulated by GTP binding and hydrolysis events that require direct interaction between structurally homologous "NG" GTPase domains of the SRP signal recognition subunit and its membrane-associated receptor, SR alpha. Structures of both the apo and GDP bound NG domains of the prokaryotic SRP54 homolog, Ffh, and the prokaryotic receptor homolog, FtsY, have been determined. The structural basis for the GTP-dependent interaction between the two proteins, however, remains unknown. RESULTS: We report here two structures of the NG GTPase of Ffh from Thermus aquaticus bound to the nonhydrolyzable GTP analog GMPPNP. Both structures reveal an unexpected binding mode in which the beta-phosphate is kinked away from the binding site and magnesium is not bound. Binding of the GTP analog in the canonical conformation found in other GTPase structures is precluded by constriction of the phosphate binding P loop. The structural difference between the Ffh complex and other GTPases suggests a specific conformational change that must accompany movement of the nucleotide from an "inactive" to an "active" binding mode. CONCLUSIONS: Conserved side chains of the GTPase sequence motifs unique to the SRP subfamily may function to gate formation of the active GTP bound conformation. Exposed hydrophobic residues provide an interaction surface that may allow regulation of the GTP binding conformation, and thus activation of the GTPase, during the association of SRP with its receptor.
About this Structure
1JPN is a Single protein structure of sequence from Thermus aquaticus. Full crystallographic information is available from OCA.
Reference
The conformation of bound GMPPNP suggests a mechanism for gating the active site of the SRP GTPase., Padmanabhan S, Freymann DM, Structure. 2001 Sep;9(9):859-67. PMID:11566135
Page seeded by OCA on Thu Mar 20 12:06:40 2008
Categories: Single protein | Thermus aquaticus | Freymann, D M. | Padmanabhan, S. | ACY | CA | GNP | Ffh | Gmppnp | Ng domain | Signal recognition particle | Srp | Srp54
