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4m0d

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Revision as of 14:55, 5 August 2016

Crystal structure of MurQ from H.influenzae in apo form

Structural highlights

4m0d is a 4 chain structure with sequence from Haein. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	4lzj
Gene:	murQ (HAEIN)
Activity:	N-acetylmuramic acid 6-phosphate etherase, with EC number 4.2.1.126
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MURQ_HAEIN] Specifically catalyzes the cleavage of the D-lactyl ether substituent of MurNAc 6-phosphate, producing GlcNAc 6-phosphate and D-lactate. Together with AnmK, is also required for the utilization of anhydro-N-acetylmuramic acid (anhMurNAc) either imported from the medium or derived from its own cell wall murein, and thus plays a role in cell wall recycling (By similarity).

Publication Abstract from PubMed

The breakdown and recycling of peptidoglycan, an essential polymeric cell structure, occur in a number of bacterial species. A key enzyme in the recycling pathway of one of the components of the peptidoglycan layer, N-acetylmuramic acid (MurNAc), is MurNAc 6-phosphate hydrolase (MurQ). This enzyme catalyzes the cofactor-independent cleavage of a relatively nonlabile ether bond and presents an interesting target for mechanistic studies. Open chain product and substrate analogues were synthesized and tested as competitive inhibitors (Kis values of 1.1 +/- 0.3 and 0.23 +/- 0.02 mM, respectively) of the MurNAc 6P hydrolase from Escherichia coli (MurQ-EC). To identify the roles of active site residues that are important for catalysis, the substrate analogue was cocrystallized with the MurNAc 6P hydrolase from Haemophilus influenzae (MurQ-HI) that was amenable to crystallographic studies. The cocrystal structure of MurQ-HI with the substrate analogue showed that Glu89 was located in the proximity of both the C2 atom and the oxygen at the C3 position of the bound inhibitor and that no other potential acid/base residue that could act as an active site acid/base was located in the vicinity. The conserved residues Glu120 and Lys239 were found within hydrogen bonding distance of the C5 hydroxyl group and C6 phosphate group, suggesting that they play a role in substrate binding and ring opening. Combining these results with previous biochemical data, we propose a one-base mechanism of action in which Glu89 functions to both deprotonate at the C2 position and assist in the departure of the lactyl ether at the C3 position. This same residue would serve to deprotonate the incoming water and reprotonate the enolate in the second half of the catalytic cycle.

Structure of MurNAc 6-phosphate hydrolase (MurQ) from Haemophilus influenzae with a bound inhibitor.,Hadi T, Hazra S, Tanner ME, Blanchard JS Biochemistry. 2013 Dec 23;52(51):9358-66. doi: 10.1021/bi4010446. Epub 2013 Nov, 22. PMID:24251551^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Hadi T, Hazra S, Tanner ME, Blanchard JS. Structure of MurNAc 6-phosphate hydrolase (MurQ) from Haemophilus influenzae with a bound inhibitor. Biochemistry. 2013 Dec 23;52(51):9358-66. doi: 10.1021/bi4010446. Epub 2013 Nov, 22. PMID:24251551 doi:http://dx.doi.org/10.1021/bi4010446

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4m0d"

@@ Line 1: / Line 1: @@
 ==Crystal structure of MurQ from H.influenzae in apo form==
 <StructureSection load='4m0d' size='340' side='right' caption='[[4m0d]], [[Resolution|resolution]] 2.58&Aring;' scene=''>
@@ Line 6: / Line 7: @@
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">murQ ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=71421 HAEIN])</td></tr>
 <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/N-acetylmuramic_acid_6-phosphate_etherase N-acetylmuramic acid 6-phosphate etherase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.126 4.2.1.126] </span></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4m0d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4m0d OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4m0d RCSB], [http://www.ebi.ac.uk/pdbsum/4m0d PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4m0d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4m0d OCA], [http://pdbe.org/4m0d PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4m0d RCSB], [http://www.ebi.ac.uk/pdbsum/4m0d PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4m0d ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 18: / Line 19: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4m0d" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

4m0d

From Proteopedia

Revision as of 14:55, 5 August 2016

Crystal structure of MurQ from H.influenzae in apo form

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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