2mi2
From Proteopedia
(Difference between revisions)
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<StructureSection load='2mi2' size='340' side='right' caption='[[2mi2]], [[NMR_Ensembles_of_Models | 15 NMR models]]' scene=''> | <StructureSection load='2mi2' size='340' side='right' caption='[[2mi2]], [[NMR_Ensembles_of_Models | 15 NMR models]]' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
| - | [[2mi2]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MI2 OCA]. <br> | + | <table><tr><td colspan='2'>[[2mi2]] is a 1 chain structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2MI2 OCA]. <br> |
| - | <b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span>< | + | </td></tr><tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span></td></tr> |
| - | <b>Resources:</b> <span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2mi2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mi2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2mi2 RCSB], [http://www.ebi.ac.uk/pdbsum/2mi2 PDBsum]</span>< | + | <tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2mi2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2mi2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2mi2 RCSB], [http://www.ebi.ac.uk/pdbsum/2mi2 PDBsum]</span></td></tr> |
| + | <table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
The twin-arginine protein transport (Tat) system translocates fully folded proteins across lipid membranes. In Escherichia coli, the Tat system comprises three essential components: TatA, TatB and TatC. The protein translocation process is proposed to initiate by signal peptide recognition and substrate binding to the TatBC complex. Upon formation of the TatBC-substrate protein complex, the TatA subunits are recruited and form the protein translocation pore. Experimental evidences suggest that TatB forms a tight complex with TatC at 1:1 molar ratio and the TatBC complex contains multiple copies of both proteins. Cross-linking experiments demonstrate that TatB functions in tetrameric units and interacts with both TatC and substrate proteins. However, structural information of the TatB protein is still lacking, and its functional mechanism remains elusive. Herein, we report the solution structure of TatB in DPC micelles determined by Nuclear Magnetic Resonance (NMR) spectroscopy. Overall, the structure shows an extended 'L-shape' conformation comprising four helices: a transmembrane helix (TMH) alpha1, an amphipathic helix (APH) alpha2, and two solvent exposed helices alpha3 and alpha4. The packing of TMH and APH is relatively rigid, whereas helices alpha3 and alpha4 display notably higher mobility. The observed floppiness of helices alpha3 and alpha4 allows TatB to sample a large conformational space, thus providing high structural plasticity to interact with substrate proteins of different sizes and shapes. | The twin-arginine protein transport (Tat) system translocates fully folded proteins across lipid membranes. In Escherichia coli, the Tat system comprises three essential components: TatA, TatB and TatC. The protein translocation process is proposed to initiate by signal peptide recognition and substrate binding to the TatBC complex. Upon formation of the TatBC-substrate protein complex, the TatA subunits are recruited and form the protein translocation pore. Experimental evidences suggest that TatB forms a tight complex with TatC at 1:1 molar ratio and the TatBC complex contains multiple copies of both proteins. Cross-linking experiments demonstrate that TatB functions in tetrameric units and interacts with both TatC and substrate proteins. However, structural information of the TatB protein is still lacking, and its functional mechanism remains elusive. Herein, we report the solution structure of TatB in DPC micelles determined by Nuclear Magnetic Resonance (NMR) spectroscopy. Overall, the structure shows an extended 'L-shape' conformation comprising four helices: a transmembrane helix (TMH) alpha1, an amphipathic helix (APH) alpha2, and two solvent exposed helices alpha3 and alpha4. The packing of TMH and APH is relatively rigid, whereas helices alpha3 and alpha4 display notably higher mobility. The observed floppiness of helices alpha3 and alpha4 allows TatB to sample a large conformational space, thus providing high structural plasticity to interact with substrate proteins of different sizes and shapes. | ||
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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> | ||
| - | == References == | + | </div>== References == |
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
Revision as of 09:18, 1 May 2014
Solution structure of the E. coli TatB protein in DPC micelles
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