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) Supplementary Data 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 CrossRef Citing Articles via Google Scholar Google Scholar Articles by Raczko, A. M. Articles by Jagusztyn-Krynicka, E. K. Search for Related Content PubMed PubMed Citation Articles by Raczko, A. M. Articles by Jagusztyn-Krynicka, E. K. Agricola Articles by Raczko, A. M. Articles by Jagusztyn-Krynicka, E. K.

Characterization of new DsbB-like thiol-oxidoreductases of Campylobacter jejuni and Helicobacter pylori and classification of the DsbB family based on phylogenomic, structural and functional criteria

Marcin Pawowski^1,2

Magdalena Lewandowska^1,

Elbieta K. Jagusztyn-Krynicka¹

¹ Department of Bacterial Genetics, Institute of Microbiology, Warsaw University, Miecznikowa 1, 02-096 Warsaw, Poland
² Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology, Trojdena 4, 02-109 Warsaw, Poland

Correspondence
E. K. Jagusztyn-Krynicka
kjkryn{at}biol.uw.edu.pl

In Gram-negative bacterial cells, disulfide bond formation occurs in the oxidative environment of the periplasm and is catalysed by Dsb (disulfide bond) proteins found in the periplasm and in the inner membrane. In this report the identification of a new subfamily of disulfide oxidoreductases encoded by a gene denoted dsbI, and functional characterization of DsbI proteins from Campylobacter jejuni and Helicobacter pylori, as well as DsbB from C. jejuni, are described. The N-terminal domain of DsbI is related to DsbB proteins and comprises five predicted transmembrane segments, while the C-terminal domain is predicted to locate to the periplasm and to fold into a -propeller structure. The dsbI gene is co-transcribed with a small ORF designated dba (dsbI-accessory). Based on a series of deletion and complementation experiments it is proposed that DsbB can complement the lack of DsbI but not the converse. In the presence of DsbB, the activity of DsbI was undetectable, hence it probably acts only on a subset of possible substrates of DsbB. To reconstruct the principal events in the evolution of DsbB and DsbI proteins, sequences of all their homologues identifiable in databases were analysed. In the course of this study, previously undetected variations on the common thiol-oxidoreductase theme were identified, such as development of an additional transmembrane helix and loss or migration of the second pair of Cys residues between two distinct periplasmic loops. In conjunction with the experimental characterization of two members of the DsbI lineage, this analysis has resulted in the first comprehensive classification of the DsbB/DsbI family based on structural, functional and evolutionary criteria.

The GenBank/EMBL/DDBJ accession number for the Campylobacter coli 72Dz/92 cjaE gene sequence reported in this paper is AJ249744.

Data on sensitivity to DTT, electron microscopy of C. jejuni mutant strains and data on the accumulation of proteins with reduced cysteines in E. coli dsbB mutants complemented by C. jejuni are available as supplementary data with the online version of this paper (at http://mic.sgmjournals.org).

Present address: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawiskiego 5a, 02-106 Warsaw, Poland.

This article has been cited by other articles:

				M. Totsika, B. Heras, D. J. Wurpel, and M. A. Schembri Characterization of Two Homologous Disulfide Bond Systems Involved in Virulence Factor Biogenesis in Uropathogenic Escherichia coli CFT073 J. Bacteriol., June 15, 2009; 191(12): 3901 - 3908. [Abstract] [Full Text] [PDF]

				K. Inaba, Y.-h. Takahashi, K. Ito, and S. Hayashi Critical role of a thiolate-quinone charge transfer complex and its adduct form in de novo disulfide bond generation by DsbB PNAS, January 10, 2006; 103(2): 287 - 292. [Abstract] [Full Text] [PDF]