Bangia fusco-purpurea Polysaccharide Promotes Akkermansia muciniphila Growth and Colonization: Integrated Proteomic and Metabolomic Insights

• BFP significantly promoted the growth and colonization of A. muciniphila . • BFP enhanced SCFAs production and expression of MUC-2 and tight junction proteins. • Colonization-related proteins (murE, pyk, guaB) were upregulated under BFP treatment. • BFP modulated purine metabolism and cGMP-PKG, tryptophan-related pathways. • Integrated omics revealed A. muciniphila adapts to polysaccharide-rich conditions. Akkermansia muciniphila plays a key role in maintaining gut barrier integrity, but its interaction with dietary polysaccharides remains unknown. This study investigated the effects of Bangia fusco-purpurea polysaccharide (BFP) on the growth and metabolic activity of A. muciniphila . The results showed that BFP significantly enhanced bacterial growth and short-chain fatty acid production in a dose-dependent manner. Compared with A. muciniphila in a carbon-free medium, integrated proteomic and metabolomic analyses revealed significant changes at the incubation of with 2.00 g/L BFP, including 38 differentially expressed proteins and 157 metabolites. Notably, upregulation of colonization-associated proteins (e.g., MurE, Pyk, GuaB) was observed, along with elevated levels of purine-related metabolites such as guanosine monophosphate and ribose 1-phosphate. Pathway analysis indicated modulation of purine metabolism, cGMP-PKG signaling, and tryptophan metabolism, suggesting that BFP shapes the metabolic adaptation of A. muciniphila in polysaccharide-rich environments. Furthermore, BFP enhanced the expression of MUC-2 and tight junction proteins (ZO-1, Occludin, Claudin), implying the improved intestinal barrier-enhancing effect. These findings demonstrated that BFP can promote A. muciniphila colonization through metabolic reprogramming, supporting its potential application in microbiota-targeted dietary strategies.