1np4: Difference between revisions
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< | ==CRYSTAL STRUCTURE OF NITROPHORIN 4 FROM RHODNIUS PROLIXUS== | ||
<StructureSection load='1np4' size='340' side='right'caption='[[1np4]], [[Resolution|resolution]] 1.50Å' scene=''> | |||
You may | == Structural highlights == | ||
or the | <table><tr><td colspan='2'>[[1np4]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Rhodnius_prolixus Rhodnius prolixus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NP4 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NP4 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]] 1.5Å</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=NH3:AMMONIA'>NH3</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=1np4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1np4 OCA], [https://pdbe.org/1np4 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1np4 RCSB], [https://www.ebi.ac.uk/pdbsum/1np4 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1np4 ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/NP4_RHOPR NP4_RHOPR] Heme-based protein that deliver nitric oxide gas (NO) to the victim while feeding, resulting in vasodilation and inhibition of platelet aggregation. Also bind tightly to histamine, which is released by the host to induce wound healing (By similarity). | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/np/1np4_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</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/main_output.php?pdb_ID=1np4 ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
BACKGROUND: Nitrophorins are nitric oxide (NO) transport proteins from the saliva of blood-feeding insects, which act as vasodilators and anti-platelet agents. Rhodnius prolixus, an insect that carries the trypanosome that causes Chagas' disease, releases four NO-loaded nitrophorins during blood feeding, whereupon the ligand is released into the bloodstream or surrounding tissue of the host. Histamine, a signaling molecule released by the host upon tissue damage, is tightly bound by the nitrophorins; this may facilitate the release of NO and reduce inflammation in the host. RESULTS: Recombinant nitrophorin 4 (NP4) was expressed in Escherichia coli, reconstituted with heme, and found to bind NO and histamine in a manner similar to that of the natural protein. The crystal structure of NP4 revealed a lipocalin-like eight-stranded beta barrel, with heme inserted into one end of the barrel. His59 ligates the proximal site on the heme, a solvent molecule (NH3) ligates the distal site, and three additional solvent molecules occupy the distal pocket. Buried in the protein interior are Glu55 and three solvent molecules. A detailed comparison with other lipocalins suggests that NP4 is closely related to the biliverdin-binding proteins from insects. CONCLUSIONS: The nitrophorins have a unique hemoprotein structure and are completely unlike the globins, the only other hemoproteins designed to transport dissolved gases. Compared with the recently described structure of NP1, the NP4 structure is considerably higher resolution, confirms the unusual placement of ionizable groups in the protein interior, and clarifies the solvent arrangement in the distal pocket. It also provides a striking example of structural homology where sequence homology is minimal. | |||
The crystal structure of nitrophorin 4 at 1.5 A resolution: transport of nitric oxide by a lipocalin-based heme protein.,Andersen JF, Weichsel A, Balfour CA, Champagne DE, Montfort WR Structure. 1998 Oct 15;6(10):1315-27. PMID:9782054<ref>PMID:9782054</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1np4" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Nitrophorin|Nitrophorin]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | [[Category: Large Structures]] | ||
== | |||
[[Category: Rhodnius prolixus]] | [[Category: Rhodnius prolixus]] | ||
[[Category: Andersen JF]] | |||
[[Category: Andersen | [[Category: Balfour CA]] | ||
[[Category: Balfour | [[Category: Champagne DE]] | ||
[[Category: Champagne | [[Category: Montfort WR]] | ||
[[Category: Montfort | [[Category: Weichsel A]] | ||
[[Category: Weichsel | |||
Latest revision as of 03:18, 21 November 2024
CRYSTAL STRUCTURE OF NITROPHORIN 4 FROM RHODNIUS PROLIXUSCRYSTAL STRUCTURE OF NITROPHORIN 4 FROM RHODNIUS PROLIXUS
Structural highlights
FunctionNP4_RHOPR Heme-based protein that deliver nitric oxide gas (NO) to the victim while feeding, resulting in vasodilation and inhibition of platelet aggregation. Also bind tightly to histamine, which is released by the host to induce wound healing (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedBACKGROUND: Nitrophorins are nitric oxide (NO) transport proteins from the saliva of blood-feeding insects, which act as vasodilators and anti-platelet agents. Rhodnius prolixus, an insect that carries the trypanosome that causes Chagas' disease, releases four NO-loaded nitrophorins during blood feeding, whereupon the ligand is released into the bloodstream or surrounding tissue of the host. Histamine, a signaling molecule released by the host upon tissue damage, is tightly bound by the nitrophorins; this may facilitate the release of NO and reduce inflammation in the host. RESULTS: Recombinant nitrophorin 4 (NP4) was expressed in Escherichia coli, reconstituted with heme, and found to bind NO and histamine in a manner similar to that of the natural protein. The crystal structure of NP4 revealed a lipocalin-like eight-stranded beta barrel, with heme inserted into one end of the barrel. His59 ligates the proximal site on the heme, a solvent molecule (NH3) ligates the distal site, and three additional solvent molecules occupy the distal pocket. Buried in the protein interior are Glu55 and three solvent molecules. A detailed comparison with other lipocalins suggests that NP4 is closely related to the biliverdin-binding proteins from insects. CONCLUSIONS: The nitrophorins have a unique hemoprotein structure and are completely unlike the globins, the only other hemoproteins designed to transport dissolved gases. Compared with the recently described structure of NP1, the NP4 structure is considerably higher resolution, confirms the unusual placement of ionizable groups in the protein interior, and clarifies the solvent arrangement in the distal pocket. It also provides a striking example of structural homology where sequence homology is minimal. The crystal structure of nitrophorin 4 at 1.5 A resolution: transport of nitric oxide by a lipocalin-based heme protein.,Andersen JF, Weichsel A, Balfour CA, Champagne DE, Montfort WR Structure. 1998 Oct 15;6(10):1315-27. PMID:9782054[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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