1f7z: Difference between revisions
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|PDB= 1f7z |SIZE=350|CAPTION= <scene name='initialview01'>1f7z</scene>, resolution 1.55Å | |PDB= 1f7z |SIZE=350|CAPTION= <scene name='initialview01'>1f7z</scene>, resolution 1.55Å | ||
|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand= | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene> | ||
|ACTIVITY= [http://en.wikipedia.org/wiki/Trypsin Trypsin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.4 3.4.21.4] | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Trypsin Trypsin], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.4 3.4.21.4] </span> | ||
|GENE= | |GENE= | ||
|DOMAIN= | |||
|RELATEDENTRY=[[3tgi|3TGI]], [[1f5r|1F5R]] | |||
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1f7z FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1f7z OCA], [http://www.ebi.ac.uk/pdbsum/1f7z PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1f7z RCSB]</span> | |||
}} | }} | ||
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[[Category: Ringe, D.]] | [[Category: Ringe, D.]] | ||
[[Category: White, A.]] | [[Category: White, A.]] | ||
[[Category: serine protease]] | [[Category: serine protease]] | ||
[[Category: trypsin precursor]] | [[Category: trypsin precursor]] | ||
''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 20:17:49 2008'' | ||
Revision as of 20:17, 30 March 2008
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| , resolution 1.55Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Trypsin, with EC number 3.4.21.4 | ||||||
| Related: | 3TGI, 1F5R
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
RAT TRYPSINOGEN K15A COMPLEXED WITH BOVINE PANCREATIC TRYPSIN INHIBITOR
OverviewOverview
The contribution of induced fit to enzyme specificity has been much debated, although with little experimental data. Here we probe the effect of induced fit on enzyme specificity using the trypsin(ogen) system. BPTI is known to induce trypsinogen to assume a trypsinlike conformation. Correlations are observed between BPTI affinity and the values of k(cat)/K(m) for the hydrolysis of two substrates by eight trypsin(ogen) variants. The slope of both correlations is -1.8. The crystal structures of the BPTI complexes of four variant trypsinogens were also solved. Three of these enzymes, K15A, DeltaI16V17/D194N, and DeltaI16V17/Q156K trypsinogen, are 10- to 100-fold more active than trypsinogen. The fourth variant, DeltaI16V17 trypsinogen, is the lone outlier in the correlations; its activity is lower than expected based on its affinity for BPTI. The S1 site and oxyanion hole, formed by segments 184A-194 and 216-223, are trypsinlike in all of the enzymes. These structural and kinetic data confirm that BPTI induces an active conformation in the trypsin(ogen) variants. Thus, changes in BPTI affinity monitor changes in the energetic cost of inducing a trypsinlike conformation. Although the S1 site and oxyanion hole are similar in all four variants, the N-terminal and autolysis loop (residues 142-152) segments have different interactions for each variant. These results indicate that zymogen activity is controlled by a simple conformational equilibrium between active and inactive conformations, and that the autolysis loop and N-terminal segments control this equilibrium. Together, these data illustrate that induced fit does not generally contribute to enzyme specificity.
About this StructureAbout this Structure
1F7Z is a Protein complex structure of sequences from Bos taurus and Rattus norvegicus. Full crystallographic information is available from OCA.
ReferenceReference
The energetic cost of induced fit catalysis: Crystal structures of trypsinogen mutants with enhanced activity and inhibitor affinity., Pasternak A, White A, Jeffery CJ, Medina N, Cahoon M, Ringe D, Hedstrom L, Protein Sci. 2001 Jul;10(7):1331-42. PMID:11420435
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