|
|
||||||||
Unité de Microbiologie et Génétique, UMR 5122 CNRS-INSA-UCBL, Université Claude Bernard Lyon I, bât. André Lwoff, 69622 Villeurbanne Cedex, France
Correspondence
Jean Claude Lazzaroni
lazzaron{at}biomserv.univ-lyon1.fr
The tol-pal genes are necessary for maintaining the outer-membrane integrity of Gram-negative bacteria. These genes were first described in Escherichia coli, and more recently in several other species. They are involved in the pathogenesis of E. coli, Haemophilus ducreyi, Vibrio cholerae and Salmonella enterica. The role of the tol-pal genes in bacterial pathogenesis was investigated in the phytopathogenic enterobacterium Erwinia chrysanthemi, assuming that this organism might be a good model for such a study. The whole Er. chrysanthemi tol-pal region was characterized. Tol-Pal proteins, except TolA, showed high identity scores with their E. coli homologues. Er. chrysanthemi mutants were constructed by introducing a uidAkan cassette in the ybgC, tolQ, tolA, tolB, pal and ybgF genes. All the mutants were hypersensitive to bile salts. Mutations in tolQ, tolA, tolB and pal were deleterious for the bacteria, which required high concentrations of sugars or osmoprotectants for their viability. Consistent with this observation, they were greatly impaired in their cell morphology and division, which was evidenced by observations of cell filaments, spherical forms, membrane blebbing and mislocalized bacterial septa. Moreover, tol-pal mutants showed a reduced virulence in a potato tuber model and on chicory leaves. This could be explained by a combination of impaired phenotypes in the tol-pal mutants, such as reduced growth and motility and a decreased production of pectate lyases, the major virulence factor of Er. chrysanthemi.
The GenBank/EMBL/DDBJ accession number for the nucleotide sequence reported in this paper, corresponding to a 6967 bp fragment, is AJ297885
This article has been cited by other articles:
![]()
![]()

![]()
![]()
![]()
V. E. Weynants, C. M. Feron, K. K. Goraj, M. P. Bos, P. A. Denoel, V. G. Verlant, J. Tommassen, I. R. A. Peak, R. C. Judd, M. P. Jennings, et al.
Additive and Synergistic Bactericidal Activity of Antibodies Directed against Minor Outer Membrane Proteins of Neisseria meningitidis
Infect. Immun.,
November 1, 2007;
75(11):
5434 - 5442.
[Abstract]
[Full Text]
[PDF]
![]()
![]()
![]()

![]()
![]()
![]()
T. F. Murphy, C. Kirkham, and A. J. Lesse
Construction of a Mutant and Characterization of the Role of the Vaccine Antigen P6 in Outer Membrane Integrity of Nontypeable Haemophilus influenzae
Infect. Immun.,
September 1, 2006;
74(9):
5169 - 5176.
[Abstract]
[Full Text]
[PDF]
![]()
HOME
HELP
FEEDBACK
SUBSCRIPTIONS
ARCHIVE
SEARCH
TABLE OF CONTENTS
Copyright © 2005 Society for General Microbiology.
INT J SYST EVOL MICROBIOL
MICROBIOLOGY
J GEN VIROL
J MED MICROBIOL
ALL SGM JOURNALS