Characterization of the probiotic and functional properties of Enterococcus faecalis AQ10 isolated from chicken cecum.

Lactic acid bacteria are considered the safest alternative to antibiotics and have a broad range of applications in animal husbandry. Enterococcus faecalis is a primary component of the chicken gut microbiota; it is known for its ability to regulate intestinal microbial balance and its probiotic functions. In this study, E. faecalis strain AQ10 from isolated from was the chicken cecum and used a combination of whole-genome sequencing and phenotypic analyses to investigate its probiotic properties. Whole-genome sequencing revealed that the genome length of E. faecalis AQ10 is 2.98 Mbp, with an average guanine-cytosine content of 38.12%, and includes 2832 protein-coding genes. Genome mining tools were used to identify an antimicrobial compound gene cluster. Additionally, E. faecalis AQ10 exhibited probiotic characteristics in vivo and antibacterial effects in vitro, with organic acids potentially contributing to its anti-Klebsiella pneumoniae activity. Metabolomics analyses revealed that the supernatant of E. faecalis AQ10 contained seven organic acids. In conclusion, E. faecalis AQ10 demonstrates significant probiotic potential and may be a suitable candidate for use in livestock and poultry breeding.