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1i5k
From Proteopedia
| Line 5: | Line 5: | ||
|SITE= | |SITE= | ||
|LIGAND= | |LIGAND= | ||
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Plasmin Plasmin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.7 3.4.21.7] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Plasmin Plasmin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.7 3.4.21.7] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1i5k FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i5k OCA], [http://www.ebi.ac.uk/pdbsum/1i5k PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1i5k RCSB]</span> | ||
}} | }} | ||
| Line 14: | Line 17: | ||
==Overview== | ==Overview== | ||
The X-ray crystal structure of a complex of a modified recombinant kringle-2 domain of human plasminogen, K2Pg[C4G/E56D/L72Y] (mK2Pg), containing an upregulated lysine-binding site, bound to a functional 30 residue internal peptide (VEK-30) from an M-type protein of a group A Streptococcus surface protein, has been determined by molecular replacement methods using K4Pg as a model, and refined at 2.7 A resolution to a R-factor of 19.5 %. The X-ray crystal structure shows that VEK-30 exists as a nearly end-to-end alpha-helix in the complex with mK2Pg. The final structure also revealed that Arg17 and His18 of VEK-30 served as cationic loci for Asp54 and Asp56 of the consensus lysine-binding site of mK2Pg, while Glu20 of VEK-30 coordinates with Arg69 of the cationic binding site of mK2Pg. The hydrophobic ligand-binding pocket in mK2Pg, consisting primarily of Trp60 and Trp70, situated between the positive and negative centers of the lysine-binding site, is utilized in a novel manner in stabilizing the interaction with VEK-30 by forming a cation-pi-electron-mediated association with the positive side-chain of Arg17 of this peptide. Additional lysine-binding sites, as well as exosite electrostatic and hydrogen bonding interactions involving Glu9 and Lys14 of VEK-30, were observed in the structural model. The importance of these interactions were tested in solution by investigating the binding constants of synthetic variants of VEK-30 to mK2Pg, and it was found that, Lys14, Arg17, His18, and Glu20 of VEK-30 were the most critical amino acid binding determinants. With regard to the solution studies, circular dichroism analysis of the titration of VEK-30 with mK2Pg demonstrated that the peptidic alpha-helical structure increased substantially when bound to the kringle module, in agreement with the X-ray results.This investigation is the first to delineate structurally the mode of interaction of the lysine-binding site of a kringle with an internal pseudo-lysine residue of a peptide or protein that functionally interacts with a kringle module, and serves as a paradigm for this important class of interactions. | The X-ray crystal structure of a complex of a modified recombinant kringle-2 domain of human plasminogen, K2Pg[C4G/E56D/L72Y] (mK2Pg), containing an upregulated lysine-binding site, bound to a functional 30 residue internal peptide (VEK-30) from an M-type protein of a group A Streptococcus surface protein, has been determined by molecular replacement methods using K4Pg as a model, and refined at 2.7 A resolution to a R-factor of 19.5 %. The X-ray crystal structure shows that VEK-30 exists as a nearly end-to-end alpha-helix in the complex with mK2Pg. The final structure also revealed that Arg17 and His18 of VEK-30 served as cationic loci for Asp54 and Asp56 of the consensus lysine-binding site of mK2Pg, while Glu20 of VEK-30 coordinates with Arg69 of the cationic binding site of mK2Pg. The hydrophobic ligand-binding pocket in mK2Pg, consisting primarily of Trp60 and Trp70, situated between the positive and negative centers of the lysine-binding site, is utilized in a novel manner in stabilizing the interaction with VEK-30 by forming a cation-pi-electron-mediated association with the positive side-chain of Arg17 of this peptide. Additional lysine-binding sites, as well as exosite electrostatic and hydrogen bonding interactions involving Glu9 and Lys14 of VEK-30, were observed in the structural model. The importance of these interactions were tested in solution by investigating the binding constants of synthetic variants of VEK-30 to mK2Pg, and it was found that, Lys14, Arg17, His18, and Glu20 of VEK-30 were the most critical amino acid binding determinants. With regard to the solution studies, circular dichroism analysis of the titration of VEK-30 with mK2Pg demonstrated that the peptidic alpha-helical structure increased substantially when bound to the kringle module, in agreement with the X-ray results.This investigation is the first to delineate structurally the mode of interaction of the lysine-binding site of a kringle with an internal pseudo-lysine residue of a peptide or protein that functionally interacts with a kringle module, and serves as a paradigm for this important class of interactions. | ||
| - | |||
| - | ==Disease== | ||
| - | Known diseases associated with this structure: Conjunctivitis, ligneous OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=173350 173350]], Plasminogen Tochigi disease OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=173350 173350]], Plasminogen deficiency, types I and II OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=173350 173350]], Thrombophilia, dysplasminogenemic OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=173350 173350]] | ||
==About this Structure== | ==About this Structure== | ||
| Line 35: | Line 35: | ||
[[Category: vek-30]] | [[Category: vek-30]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:14:56 2008'' |
Revision as of 18:14, 30 March 2008
| |||||||
| , resolution 2.7Å | |||||||
|---|---|---|---|---|---|---|---|
| Activity: | Plasmin, with EC number 3.4.21.7 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
STRUCTURE AND BINDING DETERMINANTS OF THE RECOMBINANT KRINGLE-2 DOMAIN OF HUMAN PLASMINOGEN TO AN INTERNAL PEPTIDE FROM A GROUP A STREPTOCOCCAL SURFACE PROTEIN
Overview
The X-ray crystal structure of a complex of a modified recombinant kringle-2 domain of human plasminogen, K2Pg[C4G/E56D/L72Y] (mK2Pg), containing an upregulated lysine-binding site, bound to a functional 30 residue internal peptide (VEK-30) from an M-type protein of a group A Streptococcus surface protein, has been determined by molecular replacement methods using K4Pg as a model, and refined at 2.7 A resolution to a R-factor of 19.5 %. The X-ray crystal structure shows that VEK-30 exists as a nearly end-to-end alpha-helix in the complex with mK2Pg. The final structure also revealed that Arg17 and His18 of VEK-30 served as cationic loci for Asp54 and Asp56 of the consensus lysine-binding site of mK2Pg, while Glu20 of VEK-30 coordinates with Arg69 of the cationic binding site of mK2Pg. The hydrophobic ligand-binding pocket in mK2Pg, consisting primarily of Trp60 and Trp70, situated between the positive and negative centers of the lysine-binding site, is utilized in a novel manner in stabilizing the interaction with VEK-30 by forming a cation-pi-electron-mediated association with the positive side-chain of Arg17 of this peptide. Additional lysine-binding sites, as well as exosite electrostatic and hydrogen bonding interactions involving Glu9 and Lys14 of VEK-30, were observed in the structural model. The importance of these interactions were tested in solution by investigating the binding constants of synthetic variants of VEK-30 to mK2Pg, and it was found that, Lys14, Arg17, His18, and Glu20 of VEK-30 were the most critical amino acid binding determinants. With regard to the solution studies, circular dichroism analysis of the titration of VEK-30 with mK2Pg demonstrated that the peptidic alpha-helical structure increased substantially when bound to the kringle module, in agreement with the X-ray results.This investigation is the first to delineate structurally the mode of interaction of the lysine-binding site of a kringle with an internal pseudo-lysine residue of a peptide or protein that functionally interacts with a kringle module, and serves as a paradigm for this important class of interactions.
About this Structure
1I5K is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure and binding determinants of the recombinant kringle-2 domain of human plasminogen to an internal peptide from a group A Streptococcal surface protein., Rios-Steiner JL, Schenone M, Mochalkin I, Tulinsky A, Castellino FJ, J Mol Biol. 2001 May 11;308(4):705-19. PMID:11350170
Page seeded by OCA on Sun Mar 30 21:14:56 2008
