lmo1273, a novel gene involved in Listeria monocytogenes virulence.
Listeria monocytogenes is a foodborne pathogen able to infect humans and many other mammalian species, leading to serious, often fatal disease. We have previously identified a five-gene locus in the genome of L. monocytogenes EGD-e which comprised three contiguous genes encoding paralogous type I signal peptidases. In the present study, we focused on the two distal genes of the locus (lmo1272 and lmo1273), encoding proteins sharing significant similarities with the YlqF and RnhB proteins, respectively, of Bacillus subtilis. lmo1273 could complement an Escherichia coli rnhA-rnhB thermosensitive growth phenotype, suggesting that it encodes a functional RNase H. Strikingly, inactivation of lmo1273 provoked a strong attenuation of virulence in the mouse model, and kinetic studies in infected mice revealed that multiplication of the lmo1273 mutant in target organs was significantly impaired. However, the mutation did not impair L. monocytogenes intracellular multiplication or cell-to-cell spread in cell culture models. Transcriptional profiles obtained with an lmo1273-overexpressing strain were compared to those of the wild-type strain, using microarray analyses. The data obtained suggest a pleiotropic regulatory role of Lmo1273 and possible links with amino acid uptake.
Bigot
Armelle
A
Inserm, U570, Unité de Pathogénie des Infections Systémiques, Paris F-75015, France.|Université Paris Descartes, Faculté de Médecine René Descartes, Paris F-75015, France.
Raynaud
Catherine
C
Inserm, U570, Unité de Pathogénie des Infections Systémiques, Paris F-75015, France.|Université Paris Descartes, Faculté de Médecine René Descartes, Paris F-75015, France.
Dubail
Iharilalao
I
Inserm, U570, Unité de Pathogénie des Infections Systémiques, Paris F-75015, France.|Université Paris Descartes, Faculté de Médecine René Descartes, Paris F-75015, France.
Dupuis
Marion
M
Inserm, U570, Unité de Pathogénie des Infections Systémiques, Paris F-75015, France.|Université Paris Descartes, Faculté de Médecine René Descartes, Paris F-75015, France.
Hossain
Hamid
H
Institute for Medical Microbiology, Justus-Liebig-University, Frankfurter Strasse 107, D-35392 Giessen, Germany.
Hain
Torsten
T
Institute for Medical Microbiology, Justus-Liebig-University, Frankfurter Strasse 107, D-35392 Giessen, Germany.
Chakraborty
Trinad
T
Institute for Medical Microbiology, Justus-Liebig-University, Frankfurter Strasse 107, D-35392 Giessen, Germany.
Charbit
Alain
A
Inserm, U570, Unité de Pathogénie des Infections Systémiques, Paris F-75015, France.|Université Paris Descartes, Faculté de Médecine René Descartes, Paris F-75015, France.
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D008089:Listeria monocytogenes / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D012329:RNA, Bacterial / Q000235:genetics; D016914:Ribonuclease H / Q000235:genetics / Q000378:metabolism; D014774:Virulence
D001426:Bacterial Proteins; D012329:RNA, Bacterial; D016914:Ribonuclease H