title: Transcriptome analysis of Bacillus thuringiensis spore life, germination and cell outgrowth in a vegetable-based food model.
abstract: Toxigenic species belonging to Bacillus cereus sensu lato, including Bacillus thuringiensis, cause foodborne outbreaks thanks to their capacity to survive as spores and to grow in food matrixes. The goal of this work was to assess by means of a genome-wide transcriptional assay, in the food isolate B. thuringiensis UC10070, the gene expression behind the process of spore germination and consequent outgrowth in a vegetable-based food model. Scanning electron microscopy and Energy Dispersive X-ray microanalysis were applied to select the key steps of B. thuringiensis UC10070 cell cycle to be analyzed with DNA-microarrays. At only 40 min from heat activation, germination started rapidly and in less than two hours spores transformed in active growing cells. A total of 1646 genes were found to be differentially expressed and modulated during the entire B. cereus life cycle in the food model, with most of the significant genes belonging to transport, transcriptional regulation and protein synthesis, cell wall and motility and DNA repair groups. Gene expression studies revealed that toxin-coding genes nheC, cytK and hblC were found to be expressed in vegetative cells growing in the food model.
authors.affiliation: Istituto di Microbiologia - Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy - via Milano 24, 26100 Cremona, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Bassi
authors.affiliation: Istituto di Microbiologia - Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy - via Milano 24, 26100 Cremona, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Colla
authors.affiliation: Istituto di Microbiologia - Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy - via Milano 24, 26100 Cremona, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Gazzola
authors.affiliation: Istituto di Microbiologia - Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy - via Milano 24, 26100 Cremona, Italy.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Puglisi
authors.affiliation: Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Delledonne
authors.affiliation: Istituto di Microbiologia - Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29122 Piacenza, Italy - via Milano 24, 26100 Cremona, Italy. Electronic address: pier.cocconcelli@unicatt.it.
authors.forename: Pier Sandro
authors.initials: PS
authors.lastname: Cocconcelli
mesh_terms: D001413:Bacillus thuringiensis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D008954:Models, Biological; D013171:Spores, Bacterial / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D014675:Vegetables / Q000382:microbiology*
chemical_list: D001426:Bacterial Proteins
keywords: Bacillus cereus sensu lato; Food model; Gene expression; Microarray; Spores