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Title: The Reovirus Sigmal Aspartic Acid Sandwich: A Trimerization Motif Poised for Conformational Change

Abstract

Reovirus attachment protein {sigma}1 mediates engagement of receptors on the surface of target cells and undergoes dramatic conformational rearrangements during viral disassembly in the endocytic pathway. The {sigma}1 protein is a filamentous, trimeric molecule with a globular {beta}-barrel head domain. An unusual cluster of aspartic acid residues sandwiched between hydrophobic tyrosines is located at the {sigma}1 subunit interface. A 1.75 {angstrom} structure of the {sigma}1 head domain now reveals two water molecules at the subunit interface that are held strictly in position and interact with neighboring residues. Structural and biochemical analyses of mutants affecting the aspartic acid sandwich indicate that these residues and the corresponding chelated water molecules act as a plug to block the free flow of solvent and stabilize the trimer. This arrangement of residues at the {sigma}1 head trimer interface illustrates a new protein design motif that may confer conformational mobility during cell entry.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930399
Report Number(s):
BNL-81125-2008-JA
Journal ID: ISSN 0021-9258; JBCHA3; TRN: US200904%%679
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Biological Chemistry; Journal Volume: 282
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; ASPARTIC ACID; CONFORMATIONAL CHANGES; MUTANTS; PROTEINS; RESIDUES; SOLVENTS; VIRUSES; WATER; national synchrotron light source

Citation Formats

Schelling,P., Guglielml, K., Kirchner, E., Paetzold, b., Dermody, T., and Stehle, T.. The Reovirus Sigmal Aspartic Acid Sandwich: A Trimerization Motif Poised for Conformational Change. United States: N. p., 2007. Web. doi:10.1074/jbc.M610805200.
Schelling,P., Guglielml, K., Kirchner, E., Paetzold, b., Dermody, T., & Stehle, T.. The Reovirus Sigmal Aspartic Acid Sandwich: A Trimerization Motif Poised for Conformational Change. United States. doi:10.1074/jbc.M610805200.
Schelling,P., Guglielml, K., Kirchner, E., Paetzold, b., Dermody, T., and Stehle, T.. Mon . "The Reovirus Sigmal Aspartic Acid Sandwich: A Trimerization Motif Poised for Conformational Change". United States. doi:10.1074/jbc.M610805200.
@article{osti_930399,
title = {The Reovirus Sigmal Aspartic Acid Sandwich: A Trimerization Motif Poised for Conformational Change},
author = {Schelling,P. and Guglielml, K. and Kirchner, E. and Paetzold, b. and Dermody, T. and Stehle, T.},
abstractNote = {Reovirus attachment protein {sigma}1 mediates engagement of receptors on the surface of target cells and undergoes dramatic conformational rearrangements during viral disassembly in the endocytic pathway. The {sigma}1 protein is a filamentous, trimeric molecule with a globular {beta}-barrel head domain. An unusual cluster of aspartic acid residues sandwiched between hydrophobic tyrosines is located at the {sigma}1 subunit interface. A 1.75 {angstrom} structure of the {sigma}1 head domain now reveals two water molecules at the subunit interface that are held strictly in position and interact with neighboring residues. Structural and biochemical analyses of mutants affecting the aspartic acid sandwich indicate that these residues and the corresponding chelated water molecules act as a plug to block the free flow of solvent and stabilize the trimer. This arrangement of residues at the {sigma}1 head trimer interface illustrates a new protein design motif that may confer conformational mobility during cell entry.},
doi = {10.1074/jbc.M610805200},
journal = {Journal of Biological Chemistry},
number = ,
volume = 282,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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