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2r1a

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Revision as of 07:32, 24 July 2019

Crystal structure of the periplasmic lipopolysaccharide transport protein LptA (YhbN), trigonal form

Structural highlights

2r1a is a 8 chain structure with sequence from Ecoli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	2r19
Gene:	yhbN, b3200, JW3167 (ECOLI)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT, TOPSAN

Function

[LPTA_ECOLI] Involved in the assembly of lipopolysaccharide (LPS). Required for the translocation of LPS from the inner membrane to the outer membrane. May form a bridge between the inner membrane and the outer membrane, via interactions with LptC and LptD, thereby facilitating LPS transfer across the periplasm.[HAMAP-Rule:MF_01914]^[1] ^[2] ^[3] ^[4] ^[5]

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

Lipopolysaccharide (LPS) transport protein A (LptA) is an essential periplasmic localized transport protein that has been implicated together with MsbA, LptB, and the Imp/RlpB complex in LPS transport from the inner membrane to the outer membrane, thereby contributing to building the cell envelope in Gram-negative bacteria and maintaining its integrity. Here we present the first crystal structures of processed Escherichia coli LptA in two crystal forms, one with two molecules in the asymmetric unit and the other with eight. In both crystal forms, severe anisotropic diffraction was corrected, which facilitated model building and structural refinement. The eight-molecule form of LptA is induced when LPS or Ra-LPS (a rough chemotype of LPS) is included during crystallization. The unique LptA structure represents a novel fold, consisting of 16 consecutive antiparallel beta-strands, folded to resemble a slightly twisted beta-jellyroll. Each LptA molecule interacts with an adjacent LptA molecule in a head-to-tail fashion to resemble long fibers. Site-directed mutagenesis of conserved residues located within a cluster that delineate the N-terminal beta-strands of LptA does not impair the function of the protein, although their overexpression appears more detrimental to LPS transport compared with wild-type LptA. Moreover, altered expression of both wild-type and mutated proteins interfered with normal LPS transport as witnessed by the production of an anomalous form of LPS. Structural analysis suggests that head-to-tail stacking of LptA molecules could be destabilized by the mutation, thereby potentially contributing to impair LPS transport.

Novel structure of the conserved gram-negative lipopolysaccharide transport protein A and mutagenesis analysis.,Suits MD, Sperandeo P, Deho G, Polissi A, Jia Z J Mol Biol. 2008 Jul 11;380(3):476-88. Epub 2008 Apr 26. PMID:18534617^[6]

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

References

↑ Sperandeo P, Pozzi C, Deho G, Polissi A. Non-essential KDO biosynthesis and new essential cell envelope biogenesis genes in the Escherichia coli yrbG-yhbG locus. Res Microbiol. 2006 Jul-Aug;157(6):547-58. Epub 2006 Feb 9. PMID:16765569 doi:10.1016/j.resmic.2005.11.014
↑ Sperandeo P, Cescutti R, Villa R, Di Benedetto C, Candia D, Deho G, Polissi A. Characterization of lptA and lptB, two essential genes implicated in lipopolysaccharide transport to the outer membrane of Escherichia coli. J Bacteriol. 2007 Jan;189(1):244-53. Epub 2006 Oct 20. PMID:17056748 doi:http://dx.doi.org/10.1128/JB.01126-06
↑ Sperandeo P, Lau FK, Carpentieri A, De Castro C, Molinaro A, Deho G, Silhavy TJ, Polissi A. Functional analysis of the protein machinery required for transport of lipopolysaccharide to the outer membrane of Escherichia coli. J Bacteriol. 2008 Jul;190(13):4460-9. Epub 2008 Apr 18. PMID:18424520 doi:JB.00270-08
↑ Tran AX, Trent MS, Whitfield C. The LptA protein of Escherichia coli is a periplasmic lipid A-binding protein involved in the lipopolysaccharide export pathway. J Biol Chem. 2008 Jul 18;283(29):20342-9. doi: 10.1074/jbc.M802503200. Epub 2008 , May 14. PMID:18480051 doi:http://dx.doi.org/10.1074/jbc.M802503200
↑ Sperandeo P, Villa R, Martorana AM, Samalikova M, Grandori R, Deho G, Polissi A. New insights into the Lpt machinery for lipopolysaccharide transport to the cell surface: LptA-LptC interaction and LptA stability as sensors of a properly assembled transenvelope complex. J Bacteriol. 2011 Mar;193(5):1042-53. doi: 10.1128/JB.01037-10. Epub 2010 Dec 17. PMID:21169485 doi:http://dx.doi.org/10.1128/JB.01037-10
↑ Suits MD, Sperandeo P, Deho G, Polissi A, Jia Z. Novel structure of the conserved gram-negative lipopolysaccharide transport protein A and mutagenesis analysis. J Mol Biol. 2008 Jul 11;380(3):476-88. Epub 2008 Apr 26. PMID:18534617 doi:10.1016/j.jmb.2008.04.045

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2r1a"

@@ Line 1: / Line 1: @@
 ==Crystal structure of the periplasmic lipopolysaccharide transport protein LptA (YhbN), trigonal form==
-<StructureSection load='2r1a' size='340' side='right' caption='[[2r1a]], [[Resolution|resolution]] 3.26&Aring;' scene=''>
+<StructureSection load='2r1a' size='340' side='right'caption='[[2r1a]], [[Resolution|resolution]] 3.26&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[2r1a]] is a 8 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2R1A OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2R1A FirstGlance]. <br>
@@ Line 14: / Line 14: @@
 Check<jmol>
   <jmolCheckbox>
-    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/r1/2r1a_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/r1/2r1a_consurf.spt"</scriptWhenChecked>
     <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
     <text>to colour the structure by Evolutionary Conservation</text>
@@ Line 34: / Line 34: @@
 </StructureSection>
 [[Category: Ecoli]]
+[[Category: Large Structures]]
 [[Category: Structural genomic]]
 [[Category: Jia, Z]]

2r1a

From Proteopedia

Revision as of 07:32, 24 July 2019

Crystal structure of the periplasmic lipopolysaccharide transport protein LptA (YhbN), trigonal form

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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