Microbiota or microbiome?

Unknown to the general public a decade ago, the word microbiome has hit the mass media in the past decade. Today, it is in everyone’s mouth, from the pharmacist to the bookstore or your supermarket food aisle. But what does it mean? Are microbiome and microbiota synonyms?

Not really!

Microbiota is the collection of microbial organisms within a community, typically used in reference to an animal host. It refers to the taxonomy (name) of microorganisms present. The most common is the digestive microbiota.

Microbiome is the collection of microorganisms and their genes living in a particular environment. It refers to the bacteria (primary) and their genes (secondary). The microbiome contains both the microbiota, their ‘theater of activity’, and the surrounding environmental conditions (Berg, et al., 2020).

Finally, metagenomics is the science related to modern microbiota studies. It is the study of the combined genomes of a community of microorganisms, the metagenome. As opposed to traditional culture-based microbial studies, metagenomics involves high throughput sequencing and bioinformatics tools. It allows a better description of the microbial taxonomic diversity and of the potential biological functions carried by the whole community.