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2aki

From Proteopedia

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Revision as of 07:19, 9 May 2018

Normal mode-based flexible fitted coordinates of a translocating SecYEG protein-conducting channel into the cryo-EM map of a SecYEG-nascent chain-70S ribosome complex from E. coli

Structural highlights

2aki is a 6 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	2akh
Gene:	secG ("Bacillus coli" Migula 1895), secY, prlA ("Bacillus coli" Migula 1895), secE, prlG ("Bacillus coli" Migula 1895)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[SECG_ECOLI] Subunit of the protein translocation channel SecYEG. Overexpression of some hybrid proteins has been thought to jam the protein secretion apparatus resulting in cell death; while this may be true it also results in FtsH-mediated degradation of SecY. Treatment with antibiotics that block translation elongation such as chloramphenicol also leads to degradation of SecY and SecE but not SecG. [SECE_ECOLI] Essential subunit of the protein translocation channel SecYEG. Clamps together the 2 halves of SecY. May contact the channel plug during translocation. Overexpression of some hybrid proteins has been thought to jam the protein secretion apparatus resulting in cell death; while this may be true it also results in FtsH-mediated degradation of SecY.^[1] [SECY_ECOLI] The central subunit of the protein translocation channel SecYEG. Consists of two halves formed by TMs 1-5 and 6-10. These two domains form a lateral gate at the front which open onto the bilayer between TMs 2 and 7, and are clamped together by SecE at the back. The channel is closed by both a pore ring composed of hydrophobic SecY resides and a short helix (helix 2A) on the extracellular side of the membrane which forms a plug. The plug probably moves laterally to allow the channel to open. The ring and the pore may move independently. SecY is required to insert newly synthesized SecY into the inner membrane. Overexpression of some hybrid proteins has been thought to jam the protein secretion apparatus resulting in cell death; while this may be true, overexpression also results in FtsH-mediated degradation of SecY.[HAMAP-Rule:MF_01465]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Secreted and membrane proteins are translocated across or into cell membranes through a protein-conducting channel (PCC). Here we present a cryo-electron microscopy reconstruction of the Escherichia coli PCC, SecYEG, complexed with the ribosome and a nascent chain containing a signal anchor. This reconstruction shows a messenger RNA, three transfer RNAs, the nascent chain, and detailed features of both a translocating PCC and a second, non-translocating PCC bound to mRNA hairpins. The translocating PCC forms connections with ribosomal RNA hairpins on two sides and ribosomal proteins at the back, leaving a frontal opening. Normal mode-based flexible fitting of the archaeal SecYEbeta structure into the PCC electron microscopy densities favours a front-to-front arrangement of two SecYEG complexes in the PCC, and supports channel formation by the opening of two linked SecY halves during polypeptide translocation. On the basis of our observation in the translocating PCC of two segregated pores with different degrees of access to bulk lipid, we propose a model for co-translational protein translocation.

Structure of the E. coli protein-conducting channel bound to a translating ribosome.,Mitra K, Schaffitzel C, Shaikh T, Tama F, Jenni S, Brooks CL 3rd, Ban N, Frank J Nature. 2005 Nov 17;438(7066):318-24. PMID:16292303^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Froderberg L, Houben EN, Baars L, Luirink J, de Gier JW. Targeting and translocation of two lipoproteins in Escherichia coli via the SRP/Sec/YidC pathway. J Biol Chem. 2004 Jul 23;279(30):31026-32. Epub 2004 May 12. PMID:15140892 doi:10.1074/jbc.M403229200
↑ Mitra K, Schaffitzel C, Shaikh T, Tama F, Jenni S, Brooks CL 3rd, Ban N, Frank J. Structure of the E. coli protein-conducting channel bound to a translating ribosome. Nature. 2005 Nov 17;438(7066):318-24. PMID:16292303 doi:http://dx.doi.org/10.1038/nature04133

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2aki"

@@ Line 1: / Line 1: @@
 ==Normal mode-based flexible fitted coordinates of a translocating SecYEG protein-conducting channel into the cryo-EM map of a SecYEG-nascent chain-70S ribosome complex from E. coli==
 <StructureSection load='2aki' size='340' side='right' caption='[[2aki]], [[Resolution|resolution]] 14.90&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2akh|2akh]]</td></tr>
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">secG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895]), secY, prlA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895]), secE, prlG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</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=2aki FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aki OCA], [http://pdbe.org/2aki PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2aki RCSB], [http://www.ebi.ac.uk/pdbsum/2aki PDBsum]</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=2aki FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2aki OCA], [http://pdbe.org/2aki PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2aki RCSB], [http://www.ebi.ac.uk/pdbsum/2aki PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2aki ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 13: / Line 14: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ak/2aki_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ak/2aki_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>

2aki

From Proteopedia

Revision as of 07:19, 9 May 2018

Normal mode-based flexible fitted coordinates of a translocating SecYEG protein-conducting channel into the cryo-EM map of a SecYEG-nascent chain-70S ribosome complex from E. coli

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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