HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplemental Research Data All Versions of this Article: ps.062246706v1 15/8/1907    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Makabe, K. Articles by Koide, S. Search for Related Content PubMed PubMed Citation Articles by Makabe, K. Articles by Koide, S. Social Bookmarking                   What's this?

Atomic-resolution crystal structure of Borrelia burgdorferi outer surface protein A via surface engineering

Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637, USA

(RECEIVED March 27, 2006; FINAL REVISION May 7, 2006; ACCEPTED May 8, 2006)

Outer surface protein A (OspA) from Borrelia burgdorferi has an unusual dumbbell-shaped structure in which two globular domains are connected with a "single-layer" -sheet (SLB). The protein is highly soluble, and it has been recalcitrant to crystallization. Only OspA complexes with Fab fragments have been successfully crystallized. OspA contains a large number of Lys and Glu residues, and these "high entropy" residues may disfavor crystal packing because some of them would need to be immobilized in forming a crystal lattice. We rationally designed a total of 13 surface mutations in which Lys and Glu residues were replaced with Ala or Ser. We successfully crystallized the mutant OspA without a bound Fab fragment and extended structure analysis to a 1.15 Å resolution. The new high-resolution structure revealed a unique backbone hydration pattern of the SLB segment in which water molecules fill the "weak spots" on both faces of the antiparallel -sheet. These well-defined water molecules provide additional structural links between adjacent -strands, and thus they may be important for maintaining the rigidity of the SLB that inherently lacks tight packing afforded by a hydrophobic core. The structure also revealed new information on the side-chain dynamics and on a solvent-accessible cavity in the core of the C-terminal globular domain. This work demonstrates the utility of extensive surface mutation in crystallizing recalcitrant proteins and dramatically improving the resolution of crystal structures, and provides new insights into the stabilization mechanism of OspA.

Keywords: crystallization; crystal packing; hydration; antiparallel -sheet; conformational entropy; Lyme disease

CiteULike

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				L. Goldschmidt, D. R. Cooper, Z. S. Derewenda, and D. Eisenberg Toward rational protein crystallization: A Web server for the design of crystallizable protein variants Protein Sci., August 1, 2007; 16(8): 1569 - 1576. [Abstract] [Full Text] [PDF]

				K. Makabe, D. McElheny, V. Tereshko, A. Hilyard, G. Gawlak, S. Yan, A. Koide, and S. Koide Atomic structures of peptide self-assembly mimics PNAS, November 21, 2006; 103(47): 17753 - 17758. [Abstract] [Full Text] [PDF]