Genes and proteins regulation during Listeria monocytogenes FBUNT biofilm formation at 10 ºC in response to lactocin AL705

CONSTANZA MELIAN; CASTELLANO P; EMILSE BETENCOURT; SEGLI F,; MENDOZA L; VIGNOLO, G

Conferencia; 34th EFFoST International Conference; 2021

Federación Europea de Ciencia y Tecnología de los alimentos (EFFoST) y Technion, Instituto de Tecnología de Israel

Listeria monocytogenes is a foodborne pathogen able to survive and multiply under different stress conditions. The high persistence in industrial premises and foods is due to its ability to form biofilm. A strategy to overcome L. monocytogenes contamination consist in the inhibition of biofilm formation or removal of mature biofilms through antimicrobial compounds like bacteriocin. The aim of this work was analyze L. monocytogenes FBUNT genes and proteins regulated during biofilm formation at 10 °C exposed or not to the bacteriocin lactocin AL705 by using transcriptional and comparative proteomic approachs. Listeria was growth in culture media in the presence or absence of lactocin AL705 (at subinhibitory concentration) during 6 days at 10°C. Sessile cells were growth in 24-wells microplates and planktonic cells in tubes (3 ml). Genes related to aggregation, adhesion, virulence, biofilm formation and stress factors were evaluated by PCR and RT-qPCR. The genes lmo1601, lmo1634, lmo2016 and agrA were up-regulated in biofilm cells; bacteriocin addition decreased their expression while up-regulated luxS, agrB, agrD and lmo0327. Moreover, L. monocytogenes FBUNT proteome under planktonic, lactocin AL705-treated and untreated biofilms were analyzed by nanoLC-MS/MS. Compared to planktonic growth, sessile cells involved protein abundance shifts associated with nucleic acids (Lmo0935, RsmH) and lipids (Lmo2089, GlpD) metabolisms as well as transport (Lmo1875, Lmo2372). When sessile cells were treated with lactocin AL705, proteins up-regulation were mostly related to carbohydrate metabolism and nutrient transport. Notably, transport systems as β-glucosidase IIABC (lmo0027), cellobiose (lmo2763) and trehalose (lmo1255) specific PTS proteins were highly overexpressed but mannose (lmo0098) specific PTS protein was downregulated. Results indicate that a sublethal dose of lactocin AL705 induced adaptation mechanisms in L. monocytogenes FBUNT sessile cells at 10 ºC, which would provide valuable data for specific genes targeting to control this pathogen biofilm upon the treatment with bacteriocins.