Growth-phase-dependent mobility of the lvh-encoding region in Legionella pneumophila strain Paris.
The lvh region of the Legionella pneumophila genome, which encodes a type IV secretion system, is located on a plasmid-like element in strains Paris (pP36) and Philadelphia (pLP45). The pP36 element has been described either integrated in the chromosome or excised as a multi-copy plasmid, in a similar manner to pLP45. In this paper, the chromosomal integration of pP36 in the Paris strain genome was described, occurring through site-specific recombination at the 3' end of a transfer-messenger RNA gene by recombination between attachment sites, in a similar manner to pathogenicity islands. This integration was growth-phase dependent, occurring during the exponential phase. Several pP36-borne genes were expressed during the lag phase of bacterial growth, coinciding with the peak amount of the episomal form of pP36. Expression of the same genes decreased during the exponential and stationary phases, owing to the integration phenomenon and a loss of episomal copies of pP36. A similar plasmid-like element was described in the Lens strain genome, suggesting that the mobility of the lvh region is a phenomenon widespread among Legionella sp.
Doléans-Jordheim
Anne
A
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
Akermi
Mongi
M
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
Ginevra
Christophe
C
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
Cazalet
Christel
C
Unité de Génomique des Micro-organismes Pathogènes, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
Kay
Elizabeth
E
Laboratoire Adaptation et Pathogénie des Micro-organismes, CNRS UMR5163, Université Joseph Fourier-Institut Jean Roget, 38700 La Tronche, France.
Schneider
Dominique
D
Laboratoire Adaptation et Pathogénie des Micro-organismes, CNRS UMR5163, Université Joseph Fourier-Institut Jean Roget, 38700 La Tronche, France.
Buchrieser
Carmen
C
Unité de Génomique des Micro-organismes Pathogènes, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
Atlan
Danièle
D
Unité de Microbiologie et Génétique UMR 5122, Université Claude Bernard Lyon 1, Bât. Lwoff, 10 rue Dubois, 69622 Villeurbanne, France.
Vandenesch
François
F
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
Etienne
Jerome
J
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
Jarraud
Sophie
S
INSERM, E0230, Lyon, F-69008 France; Université Lyon 1, Centre National de référence des Legionella, Faculté Laennec, Lyon, F-69008 France.
D001287:Attachment Sites, Microbiological / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D002876:Chromosomes, Bacterial / Q000235:genetics*; D015870:Gene Expression; D020071:Interspersed Repetitive Sequences; D016952:Legionella pneumophila / Q000235:genetics* / Q000254:growth & development; D010957:Plasmids / Q000235:genetics*; D012329:RNA, Bacterial / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction
D001426:Bacterial Proteins; C459580:Lvh protein, Legionella pneumophila; D012329:RNA, Bacterial; D012333:RNA, Messenger