Differential Proteomic Analysis of Lactic Acid Bacteria—Escherichia coli O157:H7 Interaction and Its Contribution to Bioprotection Strategies in Meat

ORIHUEL, ALEJANDRA; TERÁN, LUCRECIA; RENAUT, JENNY; VIGNOLO, GRACIELA M.; DE ALMEIDA, ANDRÉ M.; SAAVEDRA, LUCILA; FADDA, SILVINA

Frontiers in Microbiology

Frontiers Editorial Office

Año: 2018 vol. 9

Human infection by Enterohemorrhagic Escherichia (E.) coli (EHEC) occurs through theingestion of contaminated foods such as milk, vegetable products, water-based drinks,and particularly minced meats. Indeed EHEC is a pathogen that threatens public healthand meat industry. The potential of different Lactic Acid Bacteria (LAB) strains to controlEHEC in a meat-based medium was evaluated by using a simple and rapid method andby analyzing the growth kinetics of co-cultures (LAB-EHEC) in a meat-based medium.The activity of LAB toward EHEC in co-cultures showed variable inhibitory effect.Although, LAB were able to control EHEC, neither the produced acid nor bacteriocinswere responsible of the inhibition. The bacteriocinogenic Enteroccus (Ent.) mundtiiCRL35 presented one of the highest inhibition activities. A proteomic approach was usedto evaluate bacterial interaction and antagonistic mechanisms between Ent. mundtii andEHEC. Physiological observations, such as growth kinetics, acidification ability and EHECinhibitory potential were supported by the proteomic results, demonstrating significantdifferences in protein expression in LAB: (i) due to the presence of the pathogen and(ii) according to the growth phase analyzed. Most of the identified proteins belonged tocarbohydrate/amino acid metabolism, energy production, transcription/translation, andcell division. These results contribute to the knowledge of competition strategies usedby Ent. mundtii during its co-culture with EHEC setting new perspectives for the use ofLAB to control this pathogen in meat.