BUM6-mice gut fecal bacteria Targeted Locus (Loci)

Butyrate-producing bacteria (BPBs) have been suggested as promising probiotics due to their depletion in the dysbiotic gut microbiota associated with inflammatory bowel diseases. However, a human-derived butyrate-producing strain, Anaerostipes hadrus BPB5, significantly aggravated the DSS-induced colitis in mice in this study. Isolated from fecal sample of a healthy adult, BPB5 contained the but-associated butyrate-producing pathway in its genome and produced butyrate and hydrogen from in vitro carbohydrates fermentation. BPB5 induced significantly earlier weight loss, more severe disease scores and much higher mortality than mice treated with DSS alone. Gut microbiota in BPB5-inoculated mice followed a similar trajectory of structural shifting but moved to the disease space 3 days earlier than the control group. Co-abundance group (CAG) network analysis of 83 OTUs responding to the treatments showed dramatic increase of a CAG containing Akkermansia as a dominant member after 7 days treated with DSS, but it reached even higher abundance after only 4 days in BPB5-inoculated mice. Thus, the aggravation of DSS-induced colitis in mice by this human-derived butyrate producer may be driven by an accelerated and more dramatic disturbance of the structural dynamics of the gut ecological network during disease progression.