The Impact of a Consortium of Fermented Milk Strains on the Gut Microbiome of Gnotobiotic Mice and Monozygotic Twins

“The results also showed that (i) consumption of an FMP containing five bacterial strains was not associated with a statistically significant change in the proportional representation of resident community members within and between individuals; (ii) the appearance and disappearance of strains comprising the FMP consortium did not exhibit familial patterns in the fecal microbiota; and (iii) B. animalis subsp. lactis CNCM I-2494 was the most prominent assayed member of the consortium represented in the microbiota during the 7-week period of FMP The results also showed that (i) consumption of an FMP containing five bacterial strains was not associated with a statistically significant change in the proportional representation of resident community members within and between individuals; (ii) the appearance and disappearance of strains comprising the FMP consortium did not exhibit familial patterns in the fecal microbiota; and (iii) B. animalis subsp. lactis CNCM I-2494 was the most prominent assayed member of the consortium represented in the microbiota during the 7-week period of FMP consumption. Analyses of the fecal gene repertoire over the course of the 16 weeks of the experiment indicated that (i) variations in the functional features of the (fecal) microbiome were less than the variations in bacterial species composition; (ii) there was no significant difference in the degree of similarity in representation of KEGG orthology group functions for a given co-twin at each time point compared to the degree of similarity that existed between co-twins, whereas individual and twin pair microbiomes were significantly more similar to one another than those from unrelated individuals; and (iii) there were no statistically significant changes in the representation of these functions when the FMP strain consortium was being consumed.”

This is a seminal paper in probiotic research. I have seen a ton of papers on this subject, but none were as thorough as this one. The one concern I had was that there was no control for the FMP (fermented milk product) matrix (I don’t know what to call it, but the fermented milk without the bacteria). I still think there might be a positive effect on the gut microbiome from that matrix.

But, these folks saw similar effects in humans who ate FMP and the mice who had only the bacteria that were found in the FMP, effectively showing what the effect of just the bacteria have on the microbiome.

Still, I’m curious to settle once and for all if there is any beneficial effect of the FMP matrix. My main thought here is that 1) we know that the lactose digesting bacteria help in the stomach (as seen in folks with lactose intolerance), but 2) only one bacterial species from the FMP really seems to make it all the way through the gut. Perhaps the matrix helps the microbiome or signals the microbiome to do something? In this study, it was suggested that the bacteria alone are activating specific microbiome metabolic pathway.

Fascinating stuff. Will need to dig into it more. And I just saw that there are some videos of the authors. Should be interesting.

via The Impact of a Consortium of Fermented Milk Strains on the Gut Microbiome of Gnotobiotic Mice and Monozygotic Twins. (subscription required, unfortunately).

What do you think of this work?