Enterococcus modulate cheese microbiota

We tested the effect of bacteriocin production on LAB communities as a driver of microbial diversity, using this cheese microbiota as a model system. We have used the Enterococcus genus as a model bacterium due to its frequent production of enterocins and lower populations level among the whole community. The latter allowed us to test the enterocin production at local scale (i.e. within enterococcal populations) and at global scale (i.e. within the whole community). Thus, by characterizing and quantifying LAB communities from cheese sample, and screening the enterocinogenic capabilities of enterococcal populations, we have found a general trend of higher diversity in LAB communities associated to enterocin producers. However, the highest diversity is found at low-moderate levels of enterocin producers among enterococci. Therefore, our results showed that low proportion of enterocin producers among enterococcal populations increased LAB diversity in cheese microbial communities. To what extent these results can be extended to other LAB species or even other wild microbial ecosystems will need further research. Anyhow, our study pointed out bacteriocin production as an important factor to consider in controlling LAB communities during cheese ripening.