1qt5

<StructureSection load='1qt5' size='340' side='right' caption='[[1qt5]], [[Resolution|resolution]] 1.80&Aring;' scene=''>

<table><tr><td colspan='2'>[[1qt5]] is a 1 chain structure with 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]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1QT5 FirstGlance]. <br>

</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HED:2-HYDROXYETHYL+DISULFIDE'>HED</scene><br>

<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1qtv|1qtv]], [[1qtz|1qtz]], [[1qt3|1qt3]], [[1qt4|1qt4]], [[1qt6|1qt6]], [[1qt7|1qt7]], [[1qt8|1qt8]]</td></tr>

<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><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></td></tr>

<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><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.rcsb.org/pdb/explore.do?structureId=1qt5 RCSB], [http://www.ebi.ac.uk/pdbsum/1qt5 PDBsum]</span></td></tr>

<table>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/qt/1qt5_consurf.spt"</scriptWhenChecked>

</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

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 --&gt; His, however, converts T4L from an inverting to a retaining enzyme. It is shown here that the Thr-26 --&gt; 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 --&gt; His mutant proceeds via a covalent intermediate. Further mutations (Glu-11 --&gt; His, Asp-20 --&gt; 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.

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<ref>PMID:10430876</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

</div>

[[Category: Enterobacteria phage t4]]

[[Category: Lysozyme]]

[[Category: Kuroki, R.]]

[[Category: Matthews, B W.]]

[[Category: Weaver, L H.]]

[[Category: Hydrolase]]