In vitro models for culturing complex microbial communities are progressively being used to study the effects of different factors on the modeling of in vitro-cultured microorganisms. In previous work, we validated a 3D in vitro model of the human gut microbiota based on electrospun gelatin scaffolds covered with mucins. The aim of this study was to evaluate the effect of , a pathogen responsible for food poisoning diseases in humans, on the gut microbiota grown in the model. Real-time quantitative PCR and 16S ribosomal RNA-gene sequencing were performed to obtain information on microbiota composition after introducing ATCC 14579 vegetative cells or culture supernatants. The adhesion of to intestinal mucins was also tested. The presence of induced important modifications in the intestinal communities. Notably, levels of (particularly ), , and were reduced, while abundances of and increased. In addition, was able to adhere to mucins. The results obtained from our in vitro model stress the hypothesis that is able to colonize the intestinal mucosa by stably adhering to mucins and impacting intestinal microbial communities as an additional pathogenetic mechanism during gastrointestinal infection.