1qt5
From Proteopedia
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|PDB= 1qt5 |SIZE=350|CAPTION= <scene name='initialview01'>1qt5</scene>, resolution 1.8Å | |PDB= 1qt5 |SIZE=350|CAPTION= <scene name='initialview01'>1qt5</scene>, resolution 1.8Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=HED:2-HYDROXYETHYL DISULFIDE'>HED</scene> | + | |LIGAND= <scene name='pdbligand=HED:2-HYDROXYETHYL+DISULFIDE'>HED</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1qtv|1QTV]], [[1qtz|1QTZ]], [[1qt3|1QT3]], [[1qt4|1QT4]], [[1qt6|1QT6]], [[1qt7|1QT7]], [[1qt8|1QT8]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qt5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qt5 OCA], [http://www.ebi.ac.uk/pdbsum/1qt5 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1qt5 RCSB]</span> | ||
}} | }} | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1QT5 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/ | + | 1QT5 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_t4 Enterobacteria phage t4]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QT5 OCA]. |
==Reference== | ==Reference== | ||
Structural basis of the conversion of T4 lysozyme into a transglycosidase by reengineering the active site., Kuroki R, Weaver LH, Matthews BW, Proc Natl Acad Sci U S A. 1999 Aug 3;96(16):8949-54. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10430876 10430876] | Structural basis of the conversion of T4 lysozyme into a transglycosidase by reengineering the active site., Kuroki R, Weaver LH, Matthews BW, Proc Natl Acad Sci U S A. 1999 Aug 3;96(16):8949-54. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10430876 10430876] | ||
| - | [[Category: | + | [[Category: Enterobacteria phage t4]] |
[[Category: Lysozyme]] | [[Category: Lysozyme]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: Matthews, B W.]] | [[Category: Matthews, B W.]] | ||
[[Category: Weaver, L H.]] | [[Category: Weaver, L H.]] | ||
| - | [[Category: HED]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
| - | ''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 23:18:37 2008'' |
Revision as of 20:18, 30 March 2008
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| , resolution 1.8Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Activity: | Lysozyme, with EC number 3.2.1.17 | ||||||
| Related: | 1QTV, 1QTZ, 1QT3, 1QT4, 1QT6, 1QT7, 1QT8
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
D20E MUTANT STRUCTURE OF T4 LYSOZYME
Overview
In contrast to hen egg-white lysozyme, which retains the beta-configuration of the substrate in the product, T4 lysozyme (T4L) is an inverting glycosidase. The substitution Thr-26 --> His, however, converts T4L from an inverting to a retaining enzyme. It is shown here that the Thr-26 --> His mutant is also a transglycosidase. Indeed, the transglycosylation reaction can be more effective than hydrolysis. In contrast, wild-type T4L has no detectable transglycosidase activity. The results support the prior hypothesis that catalysis by the Thr-26 --> His mutant proceeds via a covalent intermediate. Further mutations (Glu-11 --> His, Asp-20 --> Cys) of the T26H mutant lysozyme indicate that the catalytic mechanism of this mutant requires Glu-11 as a general acid but Asp-20 is not essential. The results help provide an overall rationalization for the activity of glycosidases, in which a highly conserved acid group (Glu-11 in T4L, Glu-35 in hen egg-white lysozyme) on the beta-side of the substrate acts as a proton donor, whereas alterations in the placement and chemical identity of residues on the alpha-side of the substrate can lead to catalysis with or without retention of the configuration, to transglycosidase activity, or to the formation of a stable enzyme-substrate adduct.
About this Structure
1QT5 is a Single protein structure of sequence from Enterobacteria phage t4. Full crystallographic information is available from OCA.
Reference
Structural basis of the conversion of T4 lysozyme into a transglycosidase by reengineering the active site., Kuroki R, Weaver LH, Matthews BW, Proc Natl Acad Sci U S A. 1999 Aug 3;96(16):8949-54. PMID:10430876
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