Antagonistic Effects of 090104 on Respiratory Pathogens.

In previous studies, it was demonstrated that 090104, isolated from the human nasopharynx, modulates respiratory immunity, improving protection against infections. Here, the antagonistic effect of the 090104 strain on respiratory pathogens, including , , , , and , was explored. In a series of in vitro studies, the capacity of 090104, its bacterium-like particles, and its culture supernatants to coaggregate, inhibit the growth, and change the virulent phenotype of pathogenic bacteria was evaluated. The results showed that the 090104 strain was able to exert a bacteriostatic effect on and growth. In addition, 090104 coaggregated, inhibited biofilm formation, and induced phenotypic changes in all the respiratory pathogens evaluated. In conclusion, this work demonstrated that, in addition to its beneficial effects exerted by host-microbe interactions, 090104 can enhance protection against respiratory pathogens through its microbe-microbe interactions. The mechanisms involved in such interactions should be evaluated in future research.