Previous Article | Next Article ![]()
Infection and Immunity, November 2001, p. 6707-6717, Vol. 69, No. 11
Unité des Membranes Bactériennes
Institut Pasteur (CNRS URA 2172)1 and
Unité de Bactériologie Moléculaire et
Médicale, Laboratoire des Yersinia,3 75724 Paris Cedex 15, France, and Department of Microbiology and
Immunology, University of Kentucky, Lexington, Kentucky
40536-02982
Received 10 May 2001/Returned for modification 6 July 2001/Accepted 10 August 2001
Yersinia pestis possesses a heme-protein acquisition
system (Hmu) that allows it to utilize heme and heme-protein complexes as the sole sources of iron. Analysis of the Y. pestis
CO92 genomic sequence revealed a second heme-protein acquisition gene
cluster that shares homology with the hemophore-dependent heme
acquisition system (Has system) of Serratia
marcescens. This locus consisted of the
hasRyp receptor gene, the
hasAyp hemophore gene, and genes
encoding components of the HasAyp dedicated ABC transporter
factor (hasDEyp), as well as a
tonB homologue (hasByp). By
using a reconstituted secretion system in Escherichia coli, we showed that HasAyp is a secreted
heme-binding protein and that expression of HasAyp is iron
regulated in E. coli. The use of a transcriptional
reporter fusion showed that the hasRADEB promoter is Fur
regulated and has increased activity at 37°C. Hemoglobin utilization
via the Hasyp system was studied with both E.
coli and Y. pestis, for which has
and has hmu mutant strains were used. No contribution of
the Has system to heme utilization was observed in either E.
coli or Y. pestis under the conditions we
tested. Previously it was shown that a deletion of the Hmu system had
no effect on the virulence of Y. pestis in a mouse model
of bubonic plague. An Hmu
0019-9567/01/$04.00+0 DOI: 10.1128/IAI.69.11.6707-6717.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Identification and Characterization of the Hemophore-Dependent
Heme Acquisition System of Yersinia pestis
Has
double mutant
also retained full virulence in this model of infection. This report
constitutes the first attempt to investigate the contribution of the
hemophore-dependent heme acquisition system in bacterial pathogenicity.
*
Corresponding author. Mailing address: Unité des
Membranes Bactériennes Institut Pasteur (CNRS URA 2172), 25 rue
du Dr. Roux, 75724 Paris CEDEX 15, France. Phone: (1) 33 0140 61 32 77. Fax: (1) 33 01 45 68 87 90. E-mail: jmghigo{at}pasteur.fr.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|