This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1qt7
From Proteopedia
| Line 4: | Line 4: | ||
|PDB= 1qt7 |SIZE=350|CAPTION= <scene name='initialview01'>1qt7</scene>, resolution 1.8Å | |PDB= 1qt7 |SIZE=350|CAPTION= <scene name='initialview01'>1qt7</scene>, resolution 1.8Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</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]], [[1qt5|1QT5]], [[1qt6|1QT6]], [[1qt8|1QT8]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1qt7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1qt7 OCA], [http://www.ebi.ac.uk/pdbsum/1qt7 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1qt7 RCSB]</span> | ||
}} | }} | ||
| Line 16: | Line 19: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1QT7 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/ | + | 1QT7 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=1QT7 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: Enterobacteria phage t4]] | ||
[[Category: Lysozyme]] | [[Category: Lysozyme]] | ||
| - | [[Category: Pseudomonas phage d3112]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Kuroki, R.]] | [[Category: Kuroki, R.]] | ||
[[Category: Matthews, B W.]] | [[Category: Matthews, B W.]] | ||
[[Category: Weaver, L H.]] | [[Category: Weaver, L H.]] | ||
| - | [[Category: BME]] | ||
| - | [[Category: CL]] | ||
[[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 23:18:38 2008'' |
Revision as of 20:18, 30 March 2008
| |||||||
| , resolution 1.8Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Lysozyme, with EC number 3.2.1.17 | ||||||
| Related: | 1QTV, 1QTZ, 1QT3, 1QT4, 1QT5, 1QT6, 1QT8
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
E11N Mutant 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
1QT7 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
Page seeded by OCA on Sun Mar 30 23:18:38 2008
