Dietary protein could influence cholera infection, mouse study shows

02.03.2026

Dietary protein influences V. cholerae growth, metabolism, virulence, and competition with gut microbes.

What is already known

Vibrio cholerae causes severe diarrhea and its ability to colonize the gut depends on several factors, including the competition with resident gut microbes. Studies have shown that diet influences the gut microbiota and some milk-derived proteins can inhibit cholera toxin activity. However, how specific dietary components affect V. cholerae metabolism and virulence, as well as its interactions with commensal gut bacteria, remains unclear.

What this research adds

Researchers fed mice high-protein diets and then infected the animals with V. cholerae. Casein and wheat protein restricted bacterial growth, while soy protein supported high colonization. A bacterial gene called FlrA was linked to diet-induced changes in metabolism, virulence, and a molecular “weapon” that V. cholerae uses to compete with gut microbes. Disabling flrA restored bacterial growth and the ability of the bacterium to compete with the resident microbiota.

Conclusions

The findings show that dietary protein influences V. cholerae growth, metabolism, virulence, and competition with gut microbes, suggesting that targeted dietary strategies could be used to reduce susceptibility to cholera.

Vibrio cholerae causes severe diarrhea and its ability to colonize the gut depends on several factors, including the competition with gut microbes. Now, researchers have found that dietary protein influences V. cholerae growth, metabolism, virulence, and competition with the resident microbiota.

The findings, published in Cell Host & Microbe, suggest that targeted dietary strategies could be used to reduce susceptibility to cholera.

Studies have shown that diet influences the gut microbiota and some milk-derived proteins can inhibit cholera toxin activity. However, how specific dietary components affect V. cholerae metabolism and virulence, as well as its interactions with commensal gut bacteria, remains unclear.

Researchers led by Rui Liu at the University of California, Riverside used adult mice to test how different diets affect V. cholerae infection.

Protective diets

The researchers fed mice diets high in carbohydrate, fat, or protein, including protein from casein, soy, or wheat, and then infected the animals with V. cholerae after reducing the mice’s gut microbiota with antibiotics.

Mice on high-protein diets with casein or wheat protein had much lower levels of V. cholerae colonization compared with mice on high-carbohydrate, high-fat, or soy-protein diets.

V. cholerae in mice fed casein or wheat protein appeared to alter the activity of many genes, reducing some involved in metabolism and virulence. Diets with soy protein did not trigger these changes.

Diet-driven outcomes

Further experiments revealed that one V. cholerae’s gene, called flrA, is linked to diet-induced changes in metabolism, virulence, and a molecular “weapon” that V. cholerae uses to compete with gut microbes.

Disabling flrA restored bacterial growth and the ability of the bacterium to compete with the resident microbiota, the researchers found.The findings highlight how diet and microbial interactions together may influence the outcome of V. cholerae infection. However, the authors say, “the complexity of actual human diets and microbiota means that the range of potential diet-driven outcomes of V. cholerae colonization or infection is vast and will require much additional study to fully elucidate.”