Previous Article | Next Article ![]()
Journal of Bacteriology, October 2000, p. 5779-5786, Vol. 182, No. 20
Laboratoire de Chimie Bactérienne, Institut de
Biologie Structurale et Microbiologie, Centre Nationale de la
Recherche Scientifique, 13402 Marseille Cedex 20, France
Received 1 June 2000/Accepted 2 August 2000
The bisZ gene of Escherichia coli was
previously described as encoding a minor biotin sulfoxide (BSO)
reductase in addition to the main cytoplasmic BSO reductase, BisC.
In this study, bisZ has been renamed torZ based
on the findings that (i) the torZ gene product, TorZ, is
able to reduce trimethylamine N-oxide (TMAO) more
efficiently than BSO; (ii) although TorZ is more homologous to BisC
than to the TMAO reductase TorA (63 and 42% identity, respectively),
it is located mainly in the periplasm as is TorA; (iii)
torZ belongs to the torYZ operon,
and the first gene, torY (formerly yecK),
encodes a pentahemic c-type cytochrome homologous to
the TorC cytochrome of the TorCAD respiratory system.
Furthermore, the torYZ operon encodes a third TMAO
respiratory system, with catalytic properties that are clearly
different from those of the TorCAD and the DmsABC systems. The
torYZ and the torCAD operons may
have diverged from a common ancestor, but, surprisingly, no torD homologue is found in the sequences around
torYZ. Moreover, the torYZ operon is
expressed at very low levels under the conditions tested, and, in
contrast to torCAD, it is not induced by TMAO or
dimethyl sulfoxide.
0021-9193/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
The torYZ (yecK bisZ) Operon Encodes a
Third Respiratory Trimethylamine N-Oxide Reductase in
Escherichia coli
*
Corresponding author. Mailing address: Laboratoire de
Chimie Bactérienne, Institut de Biologie Structurale et
Microbiologie, Centre Nationale de la Recherche Scientifique, 31, chemin Joseph Aiguier, BP 71, 13402 Marseille Cedex 20, France. Phone:
(33) 4 91 16 44 27. Fax: (33) 4 91 71 89 14. E-mail:
iobbi{at}ibsm.cnrs-mrs.fr.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |