title: Tannic acid-dependent modulation of selected Lactobacillus plantarum traits linked to gastrointestinal survival.
abstract: BACKGROUND
  Owing to its antimicrobial properties dietary tannins may alter the functional efficacy of probiotic lactobacilli in the gastrointestinal (GI)-tract influencing their growth, viability and molecular adaptation to the intestinal environment.
  
  
  RESULTS
  The effects of tannic acid on Lactobacillus plantarum WCFS1 were studied by in vitro growth monitoring and visualizing the morphological alteration on the cell wall using transmission electron microscopy. Growth upon tannic acid was characterized by dose-dependent reductions of initial viable counts and extended lag phases. Lag phase-cells growing upon 0.5 mM tannic acid were abnormally shaped and experienced disturbance on the cell wall such as roughness, occasional leakage and release of cell debris, but resumed growth later at tannic acid concentrations high as 2.5 mM. To gain insight on how the response to tannic acid influenced the molecular adaptation of L. plantarum to the GI-tract conditions, gene expression of selected biomarkers for GI-survival was assessed by RT-qPCR on cDNA templates synthetized from mRNA samples obtained from cells treated with 0.5 or 2 mM tannic acid. Tannic acid-dependent gene induction was confirmed for selected genes highly expressed in the gut or with confirmed roles in GI-survival. No differential expression was observed for the pbp2A gene, a biomarker negatively related with GI-survival. However PBP2A was not labeled by Bocillin FL, a fluorescent dye-labeled penicillin V derivative, in the presence of tannic acid which suggests for enhanced GI-survival reportedly associated with the inactivation of this function.
  
  
  CONCLUSIONS
  Probiotic L. plantarum WCFS1 is able to overcome the toxic effects of tannic acid. This dietary constituent modulates molecular traits linked to the adaptation to intestinal environment in ways previously shown to enhance GI-survival.
authors.affiliation: Laboratorio de Biotecnología Bacteriana, Instituto de Ciencia y Tecnología de los Alimentos y Nutrición, Consejo Superior de Investigaciones Científicas (ICTAN-CSIC), Madrid, Spain.
authors.forename: Inés
authors.initials: I
authors.lastname: Reverón
authors.forename: Héctor
authors.initials: H
authors.lastname: Rodríguez
authors.forename: Gema
authors.initials: G
authors.lastname: Campos
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Curiel
authors.forename: Carmen
authors.initials: C
authors.lastname: Ascaso
authors.forename: Alfonso V
authors.initials: AV
authors.lastname: Carrascosa
authors.forename: Alicia
authors.initials: A
authors.lastname: Prieto
authors.forename: Blanca
authors.initials: B
authors.lastname: de Las Rivas
authors.forename: Rosario
authors.initials: R
authors.lastname: Muñoz
authors.forename: Félix López
authors.initials: FL
authors.lastname: de Felipe
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D041981:Gastrointestinal Tract / Q000382:microbiology*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D048191:Lactiplantibacillus plantarum / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013634:Tannins / Q000494:pharmacology*
chemical_list: D001426:Bacterial Proteins; D013634:Tannins