View source for 7r57


==Escherichia coli type II Asparaginase N24S mutant in its apo form==
<StructureSection load='7r57' size='340' side='right'caption='[[7r57]], [[Resolution|resolution]] 1.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7r57]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7R57 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7R57 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.4&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7r57 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7r57 OCA], [https://pdbe.org/7r57 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7r57 RCSB], [https://www.ebi.ac.uk/pdbsum/7r57 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7r57 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ASPG2_ECOLI ASPG2_ECOLI] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Bacterial L-asparaginases are amidohydrolases (EC 3.5.1.1) capable of deaminating L-asparagine and, with reduced efficiency, L-glutamine. Interest in the study of L-asparaginases is driven by their use as biodrugs for the treatment of acute lymphoblastic leukemia. Here, we report for the first time the description of the molecular structure of type II asparaginase from Escherichia coli in complex with its secondary product, L-glutamate. To obtain high-quality crystals, we took advantage of the N24S variant, which has structural and functional features similar to the wild-type enzyme, but improved stability, and which yields more ordered crystals. Analysis of the structure of the N24S-L-glutamate complex (N24S-GLU) and comparison with its apo and L-aspartate-bound form confirmed that the enzyme-reduced catalytic efficiency in the presence of L-glutamine is due to L-glutamine misfitting into the enzyme-binding pocket, which causes a local change in the catalytic center geometry. Moreover, a tight interaction between the two protomers that form the enzyme active site limits the capability of L-glutamine to fit into (and to exit from) the binding pocket of E. coli L-asparaginase, explaining why the enzyme has lower glutaminolytic activity compared to other enzymes of the same family, in particular the Erwinia chrysanthemi one.

Structural Aspects of E. coli Type II Asparaginase in Complex with Its Secondary Product L-Glutamate.,Maggi M, Scotti C Int J Mol Sci. 2022 May 25;23(11):5942. doi: 10.3390/ijms23115942. PMID:35682622<ref>PMID:35682622</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7r57" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Maggi M]]
[[Category: Scotti C]]