title: Survival of Listeria monocytogenes in Soil Requires AgrA-Mediated Regulation.
abstract: In a recent paper, we demonstrated that inactivation of the Agr system affects the patterns of survival of Listeria monocytogenes (A.-L. Vivant, D. Garmyn, L. Gal, and P. Piveteau, Front Cell Infect Microbiol 4:160, http://dx.doi.org/10.3389/fcimb.2014.00160). In this study, we investigated whether the Agr-mediated response is triggered during adaptation in soil, and we compared survival patterns in a set of 10 soils. The fate of the parental strain L. monocytogenes L9 (a rifampin-resistant mutant of L. monocytogenes EGD-e) and that of a ΔagrA deletion mutant were compared in a collection of 10 soil microcosms. The ΔagrA mutant displayed significantly reduced survival in these biotic soil microcosms, and differential transcriptome analyses showed large alterations of the transcriptome when AgrA was not functional, while the variations in the transcriptomes between the wild type and the ΔagrA deletion mutant were modest under abiotic conditions. Indeed, in biotic soil environments, 578 protein-coding genes and an extensive repertoire of noncoding RNAs (ncRNAs) were differentially transcribed. The transcription of genes coding for proteins involved in cell envelope and cellular processes, including the phosphotransferase system and ABC transporters, and proteins involved in resistance to antimicrobial peptides was affected. Under sterilized soil conditions, the differences were limited to 86 genes and 29 ncRNAs. These results suggest that the response regulator AgrA of the Agr communication system plays important roles during the saprophytic life of L. monocytogenes in soil.
authors.affiliation: Université de Bourgogne, UMR1347 Agroécologie, Dijon, France INRA, UMR1347 Agroécologie, Dijon, France.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Vivant
authors.affiliation: Université de Bourgogne, UMR1347 Agroécologie, Dijon, France INRA, UMR1347 Agroécologie, Dijon, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Garmyn
authors.affiliation: INRA, UMR1347 Agroécologie, Dijon, France AgroSup Dijon, UMR1347 Agroécologie, Dijon, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Gal
authors.affiliation: Université de Bourgogne, UMR1347 Agroécologie, Dijon, France INRA, UMR1347 Agroécologie, Dijon, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Hartmann
authors.affiliation: Université de Bourgogne, UMR1347 Agroécologie, Dijon, France INRA, UMR1347 Agroécologie, Dijon, France piveteau@u-bourgogne.fr.
authors.forename: Pascal
authors.initials: P
authors.lastname: Piveteau
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008089:Listeria monocytogenes / Q000235:genetics* / Q000502:physiology*; D050296:Microbial Viability; D022661:RNA, Untranslated / Q000096:biosynthesis; D012988:Soil Microbiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D022661:RNA, Untranslated; D014157:Transcription Factors