1a4v

<StructureSection load='1a4v' size='340' side='right' caption='[[1a4v]], [[Resolution|resolution]] 1.80&Aring;' scene=''>

<table><tr><td colspan='2'>[[1a4v]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A4V OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1A4V FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Lactose_synthase Lactose synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.22 2.4.1.22] </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=1a4v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1a4v OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1a4v RCSB], [http://www.ebi.ac.uk/pdbsum/1a4v PDBsum]</span></td></tr>

[[http://www.uniprot.org/uniprot/LALBA_HUMAN LALBA_HUMAN]] Regulatory subunit of lactose synthase, changes the substrate specificity of galactosyltransferase in the mammary gland making glucose a good acceptor substrate for this enzyme. This enables LS to synthesize lactose, the major carbohydrate component of milk. In other tissues, galactosyltransferase transfers galactose onto the N-acetylglucosamine of the oligosaccharide chains in glycoproteins.

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/a4/1a4v_consurf.spt"</scriptWhenChecked>

</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/chain_selection.php?pdb_ID=2ata ConSurf].

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== Publication Abstract from PubMed ==

The high-resolution X-ray crystal structure of human alpha-lactalbumin (at 1.8 A) in the presence of an elevated level of calcium reveals a new secondary calcium binding site, 7.9 A away from the primary calcium binding site known in all alpha-lactalbumin structures so far. The new calcium binding site is different from the zinc and sulfate binding sites [Ren, J., et al. (1993) J. Biol. Chem. 268, 19292-19298] but shares common features with the manganese binding site as described by Gerkin [Gerkin, T. A. (1984) Biochemistry 23, 4688-4697]. The proximity of the manganese and calcium binding region and the location of the functional site on one side of the charged surface of the alpha-lactalbumin molecule suggest that these binding sites might play a role in the formation of the lactose synthase complex.

Structural evidence for the presence of a secondary calcium binding site in human alpha-lactalbumin.,Chandra N, Brew K, Acharya KR Biochemistry. 1998 Apr 7;37(14):4767-72. PMID:9537992<ref>PMID:9537992</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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*[[Lactalbumin|Lactalbumin]]

[[Category: Lactose synthase]]

[[Category: Acharya, K R]]

[[Category: Chandra, N]]

[[Category: Calcium binding]]