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2g3p

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Revision as of 11:08, 27 March 2020

STRUCTURE OF THE N-TERMINAL TWO DOMAINS OF THE INFECTIVITY PROTEIN G3P OF FILAMENTOUS PHAGE FD

Structural highlights

2g3p is a 2 chain structure with sequence from Bpfd. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[G3P_BPFD] Plays essential roles both in the penetration of the viral genome into the bacterial host via pilus retraction and in the extrusion process. During the initial step of infection, G3P mediates adsorption of the phage to its primary receptor, the tip of host F-pilus. Subsequent interaction with the host entry receptor tolA induces penetration of the viral DNA into the host cytoplasm. In the extrusion process, G3P mediates the release of the membrane-anchored virion from the cell via its C-terminal domain.^[1] ^[2]

Publication Abstract from PubMed

Infection of Escherichia coli by filamentous bacteriophages is mediated by the minor phage coat protein g3p and involves two distinct cellular receptors, the F' pilus and the periplasmic protein TolA. Recently we have shown that the two receptors are contacted in a sequential manner, such that binding of TolA by the N-terminal domain g3p-D1 is conditional on a primary interaction of the second g3p domain D2 with the F' pilus. In order to better understand this process, we have solved the crystal structure of the g3p-D1D2 fragment (residues 2-217) from filamentous phage fd to 1.9 A resolution and compared it to the recently published structure of the same fragment from the related Ff phage M13. While the structure of individual domains D1 and D2 of the two phages are very similar (rms<0.7 A), there is comparatively poor agreement for the overall D1D2 structure (rms>1.2 A). This is due to an apparent movement of domain D2 with respect to D1, which results in a widening of the inter-domain groove compared to the structure of the homologous M13 protein. The movement of D2 can be described as a rigid-body rotation around a hinge located at the end of a short anti-parallel beta-sheet connecting domains D1 and D2. Structural flexibility of at least parts of the D1D2 structure was also suggested by studying the thermal unfolding of g3p: the TolA binding site on D1, while fully blocked by D2 at 37 degrees C, becomes accessible after incubation at temperatures as low as 45 degrees C. Our results support a model for the early steps of phage infection whereby exposure of the coreceptor binding site on D1 is facilitated by a conformational change in the D1D2 structure, which in vivo is induced by binding to the F' pilus on the host cell and which can be mimicked in vitro by thermal unfolding.

Crystal structure of the two N-terminal domains of g3p from filamentous phage fd at 1.9 A: evidence for conformational lability.,Holliger P, Riechmann L, Williams RL J Mol Biol. 1999 May 14;288(4):649-57. PMID:10329170^[3]

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

References

↑ Deng LW, Perham RN. Delineating the site of interaction on the pIII protein of filamentous bacteriophage fd with the F-pilus of Escherichia coli. J Mol Biol. 2002 Jun 7;319(3):603-14. PMID:12054858 doi:http://dx.doi.org/10.1016/S0022-2836(02)00260-7
↑ Lorenz SH, Jakob RP, Weininger U, Balbach J, Dobbek H, Schmid FX. The Filamentous Phages fd and IF1 Use Different Mechanisms to Infect Escherichia coli. J Mol Biol. 2010 Nov 24. PMID:21110981 doi:10.1016/j.jmb.2010.11.030
↑ Holliger P, Riechmann L, Williams RL. Crystal structure of the two N-terminal domains of g3p from filamentous phage fd at 1.9 A: evidence for conformational lability. J Mol Biol. 1999 May 14;288(4):649-57. PMID:10329170 doi:10.1006/jmbi.1999.2720

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/2g3p"

@@ Line 1: / Line 1: @@
 ==STRUCTURE OF THE N-TERMINAL TWO DOMAINS OF THE INFECTIVITY PROTEIN G3P OF FILAMENTOUS PHAGE FD==
-<StructureSection load='2g3p' size='340' side='right' caption='[[2g3p]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
+<StructureSection load='2g3p' size='340' side='right'caption='[[2g3p]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[2g3p]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bpfd Bpfd]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2G3P OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2G3P FirstGlance]. <br>
@@ Line 25: / Line 25: @@
 </StructureSection>
 [[Category: Bpfd]]
+[[Category: Large Structures]]
 [[Category: Holliger, P]]
 [[Category: Williams, R L]]

2g3p

From Proteopedia

Revision as of 11:08, 27 March 2020

STRUCTURE OF THE N-TERMINAL TWO DOMAINS OF THE INFECTIVITY PROTEIN G3P OF FILAMENTOUS PHAGE FD

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

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