Fig. 6

Interactions of Blastocystis with gut bacteria and the effect on the host. Blastocystis could disrupt gut microbiota selectively. In this study, Blastocystis caused reduction of B. longum but an increase in E. coli. This could happen by several mechanisms. There is a direct effect of Blastocystis through oxidative stress, limiting the viability of obligately anaerobic bacteria. Host immune responses as induced by Blastocystis could also limit Bifidobacterium. This bacterium is important to protect the epithelial barrier from Blastocystis-mediated damage. Red and blue arrows signify negative and positive interactions respectively