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6itc

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Revision as of 22:10, 6 March 2020

Structure of a substrate engaged SecA-SecY protein translocation machine

6itc, resolution 3.45Å

Structural highlights

6itc is a 7 chain structure with sequence from "bacillus_coli"_migula_1895 "bacillus coli" migula 1895, Aeqvi, Bacsu, Camelus glama and Geotn. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Gene:	secA, div+, BSU35300 (BACSU), secY, GTNG_0125 (GEOTN), secE, GTNG_0091 (GEOTN), GFP (AEQVI)
Experimental data:	Check to display Experimental Data
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[GFP_AEQVI] Energy-transfer acceptor. Its role is to transduce the blue chemiluminescence of the protein aequorin into green fluorescent light by energy transfer. Fluoresces in vivo upon receiving energy from the Ca(2+)-activated photoprotein aequorin. [SECA_BACSU] Part of the Sec protein translocase complex. Interacts with the SecYEG preprotein conducting channel. Has a central role in coupling the hydrolysis of ATP to the transfer of proteins into and across the cell membrane, serving as an ATP-driven molecular motor driving the stepwise translocation of polypeptide chains across the membrane (By similarity).[HAMAP-Rule:MF_01382] [A4IJK8_GEOTN] 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.[HAMAP-Rule:MF_01465][RuleBase:RU000537]

Publication Abstract from PubMed

The Sec61/SecY channel allows the translocation of many proteins across the eukaryotic endoplasmic reticulum membrane or the prokaryotic plasma membrane. In bacteria, most secretory proteins are transported post-translationally through the SecY channel by the SecA ATPase. How a polypeptide is moved through the SecA-SecY complex is poorly understood, as structural information is lacking. Here, we report an electron cryo-microscopy (cryo-EM) structure of a translocating SecA-SecY complex in a lipid environment. The translocating polypeptide chain can be traced through both SecA and SecY. In the captured transition state of ATP hydrolysis, SecA's two-helix finger is close to the polypeptide, while SecA's clamp interacts with the polypeptide in a sequence-independent manner by inducing a short beta-strand. Taking into account previous biochemical and biophysical data, our structure is consistent with a model in which the two-helix finger and clamp cooperate during the ATPase cycle to move a polypeptide through the channel.

Structure of the substrate-engaged SecA-SecY protein translocation machine.,Ma C, Wu X, Sun D, Park E, Catipovic MA, Rapoport TA, Gao N, Li L Nat Commun. 2019 Jun 28;10(1):2872. doi: 10.1038/s41467-019-10918-2. PMID:31253804^[1]

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

References

↑ Ma C, Wu X, Sun D, Park E, Catipovic MA, Rapoport TA, Gao N, Li L. Structure of the substrate-engaged SecA-SecY protein translocation machine. Nat Commun. 2019 Jun 28;10(1):2872. doi: 10.1038/s41467-019-10918-2. PMID:31253804 doi:http://dx.doi.org/10.1038/s41467-019-10918-2

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/6itc"

@@ Line 1: / Line 1: @@
 ==Structure of a substrate engaged SecA-SecY protein translocation machine==
-<StructureSection load='6itc' size='340' side='right'caption='[[6itc]], [[Resolution|resolution]] 3.45&Aring;' scene=''>
+<SX load='6itc' size='340' side='right' viewer='molstar' caption='[[6itc]], [[Resolution|resolution]] 3.45&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[6itc]] is a 7 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895], [http://en.wikipedia.org/wiki/Aeqvi Aeqvi], [http://en.wikipedia.org/wiki/Bacsu Bacsu], [http://en.wikipedia.org/wiki/Camelus_glama Camelus glama] and [http://en.wikipedia.org/wiki/Geotn Geotn]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6ITC OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ITC FirstGlance]. <br>
@@ Line 23: / Line 23: @@
 ==See Also==
 *[[Green Fluorescent Protein 3D structures|Green Fluorescent Protein 3D structures]]
+*[[SecA|SecA]]
 == References ==
 <references/>
 __TOC__
-</StructureSection>
+</SX>
 [[Category: Bacillus coli migula 1895]]
 [[Category: Aeqvi]]

6itc

From Proteopedia

Revision as of 22:10, 6 March 2020

Structure of a substrate engaged SecA-SecY protein translocation machine

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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