This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Buchko, G. W.
Right arrow Articles by Kennedy, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Buchko, G. W.
Right arrow Articles by Kennedy, M. A.

 Previous Article  |  Next Article 

Journal of Bacteriology, August 2006, p. 5993-6001, Vol. 188, No. 16
0021-9193/06/$08.00+0     doi:10.1128/JB.00460-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Solution Structure of the Conserved Hypothetical Protein Rv2302 from Mycobacterium tuberculosis

Garry W. Buchko,1 Chang-Yub Kim,2 Thomas C. Terwilliger,2 and Michael A. Kennedy1*

Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington,1 Biosciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico2

Received 3 April 2006/ Accepted 2 June 2006

The Mycobacterium tuberculosis protein Rv2302 (80 residues; molecular mass of 8.6 kDa) has been characterized using nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy. While the biochemical function of Rv2302 is still unknown, recent microarray analyses show that Rv2302 is upregulated in response to starvation and overexpression of heat shock proteins and, consequently, may play a role in the biochemical processes associated with these events. Rv2302 is a monomer in solution as shown by size exclusion chromatography and NMR spectroscopy. CD spectroscopy suggests that Rv2302 partially unfolds upon heating and that this unfolding is reversible. Using NMR-based methods, the solution structure of Rv2302 was determined. The protein contains a five-strand, antiparallel ß-sheet core with one C-terminal {alpha}-helix (A61 to A75) nestled against its side. Hydrophobic interactions between residues in the {alpha}-helix and ß-strands 3 and 4 hold the {alpha}-helix near the ß-sheet core. The electrostatic potential on the solvent-accessible surface is primarily negative with the exception of a positive arginine pocket composed of residues R18, R70, and R74. Steady-state {1H}-15N heteronuclear nuclear Overhauser effects indicate that the protein's core is rigid on the picosecond timescale. The absence of amide cross-peaks for residues G13 to H19 in the 1H-15N heteronuclear single quantum correlation spectrum suggests that this region, a loop between ß-strands 1 and 2, undergoes motion on the millisecond to microsecond timescale. Dali searches using the structure closest to the average structure do not identify any high similarities to any other known protein structure, suggesting that the structure of Rv2302 may represent a novel protein fold.

* Corresponding author. Mailing address: Fundamental Sciences, Biological Sciences Division, Battelle, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-98, Richland, WA 99352. Phone: (509) 372-2168. Fax: (509) 376-2303. E-mail: ma_kennedy{at}pnl.gov.

Journal of Bacteriology, August 2006, p. 5993-6001, Vol. 188, No. 16
0021-9193/06/$08.00+0     doi:10.1128/JB.00460-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»