View source for 5e9t


==Crystal structure of GtfA/B complex==
<StructureSection load='5e9t' size='340' side='right' caption='[[5e9t]], [[Resolution|resolution]] 2.92&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5e9t]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_10558 Atcc 10558]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5E9T OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5E9T FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5e9u|5e9u]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">gtf1, gtfA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1302 ATCC 10558]), gtf2, gtfB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1302 ATCC 10558])</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=5e9t FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5e9t OCA], [http://pdbe.org/5e9t PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5e9t RCSB], [http://www.ebi.ac.uk/pdbsum/5e9t PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5e9t ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/GTF1_STRGN GTF1_STRGN]] An N-acetylglucosaminyl transferase that is part of the accessory SecA2/SecY2 system specifically required to export GspB, a serine-rich repeat cell wall protein usually encoded upstream in the same operon. Required for correct glycosylation of GspB. Upon coexpression in E.coli with Gtf2 (GtfB) glycosylates GspB constructs. Glycosylation probably occurs intracellularly.<ref>PMID:15489421</ref>  [[http://www.uniprot.org/uniprot/GTF2_STRGN GTF2_STRGN]] A stabilizing protein that is part of the accessory SecA2/SecY2 system specifically required to export GspB, a serine-rich repeat cell wall protein encoded upstream in the same operon. Required for correct glycosylation of GspB. Upon coexpression in E.coli with Gtf1 (GtfA) glycosylates GspB constructs. Stabilizes the glycosylation activity of Gtf1 (By similarity).<ref>PMID:15489421</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
O-glycosylation of Ser and Thr residues is an important process in all organisms, which is only poorly understood. Such modification is required for the export and function of adhesin proteins that mediate the attachment of pathogenic Gram-positive bacteria to host cells. Here, we have analyzed the mechanism by which the cytosolic O-glycosyltransferase GtfA/B of Streptococcus gordonii modifies the Ser/Thr-rich repeats of adhesin. The enzyme is a tetramer containing two molecules each of GtfA and GtfB. The two subunits have the same fold, but only GtfA contains an active site, whereas GtfB provides the primary binding site for adhesin. During a first phase of glycosylation, the conformation of GtfB is restrained by GtfA to bind substrate with unmodified Ser/Thr residues. In a slow second phase, GtfB recognizes residues that are already modified with N-acetylglucosamine, likely by converting into a relaxed conformation in which one interface with GtfA is broken. These results explain how the glycosyltransferase modifies a progressively changing substrate molecule.

Mechanism of a cytosolic O-glycosyltransferase essential for the synthesis of a bacterial adhesion protein.,Chen Y, Seepersaud R, Bensing BA, Sullam PM, Rapoport TA Proc Natl Acad Sci U S A. 2016 Feb 16. pii: 201600494. PMID:26884191<ref>PMID:26884191</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5e9t" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Atcc 10558]]
[[Category: Chen, Y]]
[[Category: Rapoport, T A]]
[[Category: Accessory protein translocation]]
[[Category: Complex]]
[[Category: Glycosyltransferase]]
[[Category: Transferase-chaperone complex]]