View source for 1sdx


==Crystal structure of the zinc saturated C-terminal half of bovine lactoferrin at 2.0 A resolution reveals two additional zinc binding sites==
<StructureSection load='1sdx' size='340' side='right'caption='[[1sdx]], [[Resolution|resolution]] 2.06&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1sdx]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SDX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1SDX 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]] 2.06&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=CO3:CARBONATE+ION'>CO3</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=NDG:2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE'>NDG</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=1sdx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1sdx OCA], [https://pdbe.org/1sdx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1sdx RCSB], [https://www.ebi.ac.uk/pdbsum/1sdx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1sdx ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TRFL_BOVIN TRFL_BOVIN] Transferrins are iron binding transport proteins which can bind two Fe(3+) ions in association with the binding of an anion, usually bicarbonate.<ref>PMID:8980754</ref> <ref>PMID:15222473</ref>   Lactotransferrin has antimicrobial activity. The most effective inhibitory activity was seen against E.coli and P.aeruginosa.<ref>PMID:8980754</ref> <ref>PMID:15222473</ref>   Lactoferricin B is an antimicrobial peptide. Inhibits the growth of Gram-negative and Gram-positive bacteria.<ref>PMID:8980754</ref> <ref>PMID:15222473</ref>   The lactotransferrin transferrin-like domain 1 functions as a serine protease of the peptidase S60 family that cuts arginine rich regions. This function contributes to the antimicrobial activity.<ref>PMID:8980754</ref> <ref>PMID:15222473</ref> 
== 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/sd/1sdx_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=1sdx ConSurf].
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== Publication Abstract from PubMed ==
The crystal structure of the zinc-saturated C-terminal lobe of bovine lactoferrin has been determined at 2.0 A resolution using crystals stabilized at pH 3.8. This is the first metal-saturated structure of any functional lactoferrin at such a low pH. Purified samples of proteolytically generated zinc-saturated C-terminal lobe were crystallized from 0.1 M MES buffer pH 6.5 containing 25%(v/v) polyethyleneglycol monomethyl ether 550 and 0.1 M zinc sulfate heptahydrate. The crystals were transferred to 25 mM ammonium acetate buffer containing 25%(v/v) polyethyleneglycol monomethyl ether 550 and the pH was gradually changed from 6.5 to 3.8. The X-ray intensity data were collected with a 345 mm imaging-plate scanner mounted on an RU-300 rotating-anode X-ray generator using crystals soaked in the buffer at pH 3.8. The structure was determined with the molecular-replacement method using the coordinates of the monoferric C-terminal lobe of bovine lactoferrin as a search model and was refined to an R factor of 0.192 for all data to 2.0 A resolution. The final model comprises 2593 protein atoms (residues 342-676 and 681-685), 138 carbohydrate atoms (from 11 monosaccharide units in three glycan chains), three Zn2+ ions, one CO3(2-) ion, one SO(4)2- ions and 227 water molecules. The overall folding of the present structure is essentially similar to that of the monoferric C-terminal lobe of bovine lactoferrin, although it contains Zn2+ in place of Fe3+ in the metal-binding cleft as well as two additional Zn2+ ions on the surface of the C-terminal lobe. The Zn2+ ion in the cleft remains bound to the lobe with octahedral coordination. The bidentate carbonate ion is stabilized by a network of hydrogen bonds to Ala465, Gly466, Thr459 and Arg463. The other two zinc ions also form sixfold coordinations involving symmetry-related protein and water molecules. The number of monosaccharide residues from the three glycan chains of the C-terminal lobe was 11, which is the largest number observed to date. The structure shows that the C-terminal lobe of lactoferrin is capable of sequestering a Zn2+ ion at a pH of 3.8. This implies that the zinc ions can be sequestered over a wide pH range. The glycan chain attached to Asn545 may also have some influence on iron release from the C-terminal lobe.

Structure of the zinc-saturated C-terminal lobe of bovine lactoferrin at 2.0 A resolution.,Jabeen T, Sharma S, Singh N, Bhushan A, Singh TP Acta Crystallogr D Biol Crystallogr. 2005 Aug;61(Pt 8):1107-15. Epub 2005, Jul 20. PMID:16041076<ref>PMID:16041076</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1sdx" style="background-color:#fffaf0;"></div>

==See Also==
*[[Lactoferrin|Lactoferrin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bos taurus]]
[[Category: Large Structures]]
[[Category: Jabeen T]]
[[Category: Sharma S]]
[[Category: Singh N]]
[[Category: Singh TP]]
[[Category: Singhal G]]