View source for 5vzq


==Sperm whale myoglobin V68A/I107Y with nitric oxide==
<StructureSection load='5vzq' size='340' side='right'caption='[[5vzq]], [[Resolution|resolution]] 1.79&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5vzq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Physeter_catodon Physeter catodon]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VZQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5VZQ 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]] 1.79&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=NO:NITRIC+OXIDE'>NO</scene>, <scene name='pdbligand=NO2:NITRITE+ION'>NO2</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></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=5vzq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vzq OCA], [https://pdbe.org/5vzq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5vzq RCSB], [https://www.ebi.ac.uk/pdbsum/5vzq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5vzq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MYG_PHYMC MYG_PHYMC] Serves as a reserve supply of oxygen and facilitates the movement of oxygen within muscles.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The globular dioxygen binding heme protein myoglobin (Mb) is present in several species. Its interactions with the simple nitrogen oxides, namely, nitric oxide (NO) and nitrite, have been known for decades, but the physiological relevance has only recently become more fully appreciated. We previously reported the O-nitrito mode of binding of nitrite to ferric horse heart wild-type (wt) Mb(III) and human hemoglobin. We have expanded on this work and report the interactions of nitrite with wt sperm whale (sw) Mb(III) and its H64A, H64Q, and V68A/I107Y mutants whose dissociation constants increase in the following order: H64Q &lt; wt &lt; V68A/I107Y &lt; H64A. We also report their X-ray crystal structures that reveal the O-nitrito mode of binding of nitrite to these derivatives. The Mb(II)-mediated reductions of nitrite to NO and structural data for the wt and mutant Mb(II)-NOs are described. We show that their FeNO orientations vary with distal pocket identity, with the FeNO moieties pointing toward the hydrophobic interiors when the His64 residue is present but toward the hydrophilic exterior when this His64 residue is absent in this set of mutants. This correlates with the nature of H-bonding to the bound NO ligand (nitrosyl O vs N atom). Quantum mechanics and hybrid quantum mechanics and molecular mechanics calculations help elucidate the origin of the experimentally preferred NO orientations. In a few cases, the calculations reproduce the experimentally observed orientations only when the whole protein is taken into consideration.

Nitrosyl Myoglobins and Their Nitrite Precursors: Crystal Structural and Quantum Mechanics and Molecular Mechanics Theoretical Investigations of Preferred Fe -NO Ligand Orientations in Myoglobin Distal Pockets.,Wang B, Shi Y, Tejero J, Powell SM, Thomas LM, Gladwin MT, Shiva S, Zhang Y, Richter-Addo GB Biochemistry. 2018 Aug 14;57(32):4788-4802. doi: 10.1021/acs.biochem.8b00542., Epub 2018 Jul 27. PMID:29999305<ref>PMID:29999305</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5vzq" style="background-color:#fffaf0;"></div>

==See Also==
*[[Myoglobin 3D structures|Myoglobin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Physeter catodon]]
[[Category: Richter-Addo GB]]
[[Category: Thomas LM]]
[[Category: Wang B]]