skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: EsxB, a secreted protein from B acillus anthracis forms two distinct helical bundles: Structure of Secreted EsxB and its Variants

Abstract

The EsxB protein from Bacillus anthracis belongs to the WXG100 family, a group of proteins secreted by a specialized secretion system. We have determined the crystal structures of recombinant EsxB and discovered that the small protein (~10 kDa), comprised of a helix-loop-helix (HLH) hairpin, is capable of associating into two different helical bundles. The two basic quaternary assemblies of EsxB are an antiparallel (AP) dimer and a rarely observed bisecting U (BU) dimer. This structural duality of EsxB is believed to originate from the heptad repeat sequence diversity of the first helix of its HLH hairpin, which allows for two alternative helix packing. The flexibility of EsxB and the ability to form alternative helical bundles underscore the possibility that this protein can serve as an adaptor in secretion and can form hetero-oligomeric helix bundle(s) with other secreted members of the WXG100 family, such as EsxW. The highly conserved WXG motif is located within the loop of the HLH hairpin and is mostly buried within the helix bundle suggesting that its role is mainly structural. The exact functions of the motif, including a proposed role as a secretion signal, remain unknown.

Authors:
 [1];  [2];  [1];  [3];  [1];  [3];  [2]
  1. Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439
  2. Midwest Center for Structural Genomics, Argonne National Laboratory, Argonne Illinois 60439; Department of Biosciences, Structural Biology Center, Argonne National Laboratory, Argonne Illinois 60439; Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago Illinois 60637
  3. Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Argonne Illinois 60439; Department of Microbiology, University of Chicago, Chicago Illinois 60637
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Institutes of Health (NIH); USDOE Office of Science - Office of Biological and Environmental Research
OSTI Identifier:
1391889
DOE Contract Number:  
AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
Protein Science
Additional Journal Information:
Journal Volume: 24; Journal Issue: 9; Journal ID: ISSN 0961-8368
Publisher:
The Protein Society
Country of Publication:
United States
Language:
English
Subject:
ESAT-6 like secretion system; EsxB; WXG family; antiparallel dimer; bisecting U dimer; helix bundle; tetramer; type VII secretion system

Citation Formats

Fan, Yao, Tan, Kemin, Chhor, Gekleng, Butler, Emily K., Jedrzejczak, Robert P., Missiakas, Dominique, and Joachimiak, Andrzej. EsxB, a secreted protein from B acillus anthracis forms two distinct helical bundles: Structure of Secreted EsxB and its Variants. United States: N. p., 2015. Web. doi:10.1002/pro.2715.
Fan, Yao, Tan, Kemin, Chhor, Gekleng, Butler, Emily K., Jedrzejczak, Robert P., Missiakas, Dominique, & Joachimiak, Andrzej. EsxB, a secreted protein from B acillus anthracis forms two distinct helical bundles: Structure of Secreted EsxB and its Variants. United States. doi:10.1002/pro.2715.
Fan, Yao, Tan, Kemin, Chhor, Gekleng, Butler, Emily K., Jedrzejczak, Robert P., Missiakas, Dominique, and Joachimiak, Andrzej. Fri . "EsxB, a secreted protein from B acillus anthracis forms two distinct helical bundles: Structure of Secreted EsxB and its Variants". United States. doi:10.1002/pro.2715.
@article{osti_1391889,
title = {EsxB, a secreted protein from B acillus anthracis forms two distinct helical bundles: Structure of Secreted EsxB and its Variants},
author = {Fan, Yao and Tan, Kemin and Chhor, Gekleng and Butler, Emily K. and Jedrzejczak, Robert P. and Missiakas, Dominique and Joachimiak, Andrzej},
abstractNote = {The EsxB protein from Bacillus anthracis belongs to the WXG100 family, a group of proteins secreted by a specialized secretion system. We have determined the crystal structures of recombinant EsxB and discovered that the small protein (~10 kDa), comprised of a helix-loop-helix (HLH) hairpin, is capable of associating into two different helical bundles. The two basic quaternary assemblies of EsxB are an antiparallel (AP) dimer and a rarely observed bisecting U (BU) dimer. This structural duality of EsxB is believed to originate from the heptad repeat sequence diversity of the first helix of its HLH hairpin, which allows for two alternative helix packing. The flexibility of EsxB and the ability to form alternative helical bundles underscore the possibility that this protein can serve as an adaptor in secretion and can form hetero-oligomeric helix bundle(s) with other secreted members of the WXG100 family, such as EsxW. The highly conserved WXG motif is located within the loop of the HLH hairpin and is mostly buried within the helix bundle suggesting that its role is mainly structural. The exact functions of the motif, including a proposed role as a secretion signal, remain unknown.},
doi = {10.1002/pro.2715},
journal = {Protein Science},
issn = {0961-8368},
number = 9,
volume = 24,
place = {United States},
year = {2015},
month = {7}
}

Works referenced in this record:

New LIC vectors for production of proteins from genes containing rare codons
journal, September 2013

  • Eschenfeldt, William H.; Makowska-Grzyska, Magdalena; Stols, Lucy
  • Journal of Structural and Functional Genomics, Vol. 14, Issue 4
  • DOI: 10.1007/s10969-013-9163-9

Refinement of Macromolecular Structures by the Maximum-Likelihood Method
journal, May 1997

  • Murshudov, G. N.; Vagin, A. A.; Dodson, E. J.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 53, Issue 3
  • DOI: 10.1107/S0907444996012255

Substructure solution with SHELXD
journal, September 2002

  • Schneider, Thomas R.; Sheldrick, George M.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 58, Issue 10
  • DOI: 10.1107/S0907444902011678

HKL -3000: the integration of data reduction and structure solution – from diffraction images to an initial model in minutes
journal, July 2006

  • Minor, Wladek; Cymborowski, Marcin; Otwinowski, Zbyszek
  • Acta Crystallographica Section D Biological Crystallography, Vol. 62, Issue 8
  • DOI: 10.1107/S0907444906019949

MolProbity : all-atom structure validation for macromolecular crystallography
journal, December 2009

  • Chen, Vincent B.; Arendall, W. Bryan; Headd, Jeffrey J.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 66, Issue 1
  • DOI: 10.1107/S0907444909042073

Coot model-building tools for molecular graphics
journal, November 2004

  • Emsley, Paul; Cowtan, Kevin
  • Acta Crystallographica Section D Biological Crystallography, Vol. 60, Issue 12, p. 2126-2132
  • DOI: 10.1107/S0907444904019158

Protein secretion and surface display in Gram-positive bacteria
journal, April 2012

  • Schneewind, Olaf; Missiakas, Dominique M.
  • Philosophical Transactions of the Royal Society B: Biological Sciences, Vol. 367, Issue 1592
  • DOI: 10.1098/rstb.2011.0210

The ESAT-6/WXG100 superfamily – and a new Gram-positive secretion system?
journal, May 2002


The Structural Biology Center 19ID undulator beamline: facility specifications and protein crystallographic results
journal, December 2005

  • Rosenbaum, Gerd; Alkire, Randy W.; Evans, Gwyndaf
  • Journal of Synchrotron Radiation, Vol. 13, Issue 1
  • DOI: 10.1107/S0909049505036721

Acute infection and macrophage subversion by Mycobacterium tuberculosis require a specialized secretion system
journal, October 2003

  • Stanley, S. A.; Raghavan, S.; Hwang, W. W.
  • Proceedings of the National Academy of Sciences, Vol. 100, Issue 22
  • DOI: 10.1073/pnas.2235593100

CASTp: Computed Atlas of Surface Topography of proteins
journal, July 2003


Towards complete validated models in the next generation of ARP / wARP
journal, November 2004

  • Cohen, Serge X.; Morris, Richard J.; Fernandez, Francisco J.
  • Acta Crystallographica Section D Biological Crystallography, Vol. 60, Issue 12
  • DOI: 10.1107/S0907444904027556

Molecular replacement with MOLREP
journal, December 2009

  • Vagin, Alexei; Teplyakov, Alexei
  • Acta Crystallographica Section D Biological Crystallography, Vol. 66, Issue 1
  • DOI: 10.1107/S0907444909042589

Atomic Structures of the Human Immunophilin FKBP-12 Complexes with FK506 and Rapamycin
journal, January 1993

  • Van Duyne, Gregory D.; Standaert, Robert F.; Karplus, P. Andrew
  • Journal of Molecular Biology, Vol. 229, Issue 1
  • DOI: 10.1006/jmbi.1993.1012

The CCP4 suite programs for protein crystallography
journal, September 1994


Automation of protein purification for structural genomics
journal, March 2004


Inference of Macromolecular Assemblies from Crystalline State
journal, September 2007