8tt3
From Proteopedia
(Difference between revisions)
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<table><tr><td colspan='2'>[[8tt3]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Caldimonas_thermodepolymerans Caldimonas thermodepolymerans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8TT3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8TT3 FirstGlance]. <br> | <table><tr><td colspan='2'>[[8tt3]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Caldimonas_thermodepolymerans Caldimonas thermodepolymerans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8TT3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8TT3 FirstGlance]. <br> | ||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.4Å</td></tr> | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.4Å</td></tr> | ||
| - | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=KJ9:( | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=KJ9:(2R,5S,8S)-2,5-dihydroxy-5,10-dioxo-8-[(undecanoyloxy)methyl]-4,6,9-trioxa-5lambda~5~-phosphahenicosan-1-yl+3-deoxy-alpha-L-altro-oct-2-ulopyranosidonic+acid'>KJ9</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=8tt3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8tt3 OCA], [https://pdbe.org/8tt3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8tt3 RCSB], [https://www.ebi.ac.uk/pdbsum/8tt3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8tt3 ProSAT]</span></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=8tt3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8tt3 OCA], [https://pdbe.org/8tt3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8tt3 RCSB], [https://www.ebi.ac.uk/pdbsum/8tt3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8tt3 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
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Capsular polysaccharides (CPSs) fortify the cell boundaries of many commensal and pathogenic bacteria(1). Through the ABC-transporter-dependent biosynthesis pathway, CPSs are synthesized intracellularly on a lipid anchor and secreted across the cell envelope by the KpsMT ABC transporter associated with the KpsE and KpsD subunits(1,2). Here we use structural and functional studies to uncover crucial steps of CPS secretion in Gram-negative bacteria. We show that KpsMT has broad substrate specificity and is sufficient for the translocation of CPSs across the inner bacterial membrane, and we determine the cell surface organization and localization of CPSs using super-resolution fluorescence microscopy. Cryo-electron microscopy analyses of the KpsMT-KpsE complex in six different states reveal a KpsE-encaged ABC transporter, rigid-body conformational rearrangements of KpsMT during ATP hydrolysis and recognition of a glycolipid inside a membrane-exposed electropositive canyon. In vivo CPS secretion assays underscore the functional importance of canyon-lining basic residues. Combined, our analyses suggest a molecular model of CPS secretion by ABC transporters. | Capsular polysaccharides (CPSs) fortify the cell boundaries of many commensal and pathogenic bacteria(1). Through the ABC-transporter-dependent biosynthesis pathway, CPSs are synthesized intracellularly on a lipid anchor and secreted across the cell envelope by the KpsMT ABC transporter associated with the KpsE and KpsD subunits(1,2). Here we use structural and functional studies to uncover crucial steps of CPS secretion in Gram-negative bacteria. We show that KpsMT has broad substrate specificity and is sufficient for the translocation of CPSs across the inner bacterial membrane, and we determine the cell surface organization and localization of CPSs using super-resolution fluorescence microscopy. Cryo-electron microscopy analyses of the KpsMT-KpsE complex in six different states reveal a KpsE-encaged ABC transporter, rigid-body conformational rearrangements of KpsMT during ATP hydrolysis and recognition of a glycolipid inside a membrane-exposed electropositive canyon. In vivo CPS secretion assays underscore the functional importance of canyon-lining basic residues. Combined, our analyses suggest a molecular model of CPS secretion by ABC transporters. | ||
| - | + | , PMID:38570679<ref>PMID:38570679</ref> | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
Current revision
S. thermodepolymerans KpsM-KpsE in Glycolipid 2 state with rigid body fitted KpsT
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