Bacteroidales

Ecological Role#

Fiber fermentation: Bacteroidales encode extensive PUL systems for degrading dietary fiber, resistant starch, and host-derived glycans (mucin)—making them the primary fiber-fermenting order in the gut.

SCFA production: Major producers of propionate and acetate (less Butyrate than Firmicutes). Bile acid metabolism: Bacteroidales possess bile salt hydrolases that deconjugate primary bile acids.

Diet-responsive: Mediterranean and fiber-rich diets increase Bacteroidales abundance.^{[1]Latorre-Pérez 2021 — The Spanish Gut Microbiome Reveals Links Between Microorganisms and Mediterranean DietAdriel Latorre-Pérez, Marta Hernández, Jose Ramón Iglesias et al. · 2021Open reference 1 ↓[2]The interplay between diet and the gut microbiome: implications for health and diseaseFiona C. Ross, Dhrati Patangia, Ghjuvan Grimaud et al. · 2024Open reference 2 ↓}

Disease Associations#

T1D: Altered Bacteroidales in autoimmune beta-cell destruction.^{[3]Honkanen 2020 — Fungal Dysbiosis and Intestinal Inflammation in Children with Beta-Cell AutoimmunityJarno Honkanen, Arja Vuorela, Daniel Muthas et al. · 2020Open reference 3 ↓} CRC: Immunotherapy response (PD-1 blockade) associated with Bacteroidales abundance.^{[4]Gut Microbiome Influences the Efficacy of PD-1 Antibody Immunotherapy on MSS-Type Colorectal Cancer via Metabolic PathwayXinjian Xu, Ji Lv, Fang Guo et al. · 2020Open reference 4 ↓} CKD: Dietary fiber modulates Bacteroidales and downstream metabolome.^{[5]Hall et al. 2020 — CKD in Cats Alters Response of the Plasma Metabolome and Fecal Microbiome to Dietary FiberJean A. Hall, Matthew I. Jackson, Dennis E. Jewell et al. · 2020Open reference 5 ↓}