SRA

The importance of culturing, sequencing and studying the genomes of the bacteria that exist within our microbiomes is now undisputed. Our recent work culturing and genome sequencing of bacterial isolates from healthy gastrointestinal microbiomes in UK and North America participants has resulted in identification and classification of over 100 novel species (Nature 2016; Nature Biotech 2019); however, computational analysis of all publicly available gastrointestinal metagenome samples from healthy individuals suggests at least 2000 novel species remain to be purified and genome sequenced. Despite this incredible diversity, these metagenomic samples are heavily biased towards northern hemisphere populations (8,429 compared to 28) and as a consequence may substantially underestimate the total number of species that remain to be cultured. These limitations necessitate significant sampling efforts in Africa, South America and Australia, particularly given the different lifestyle patterns and prevalence of hunter-gatherer and uncontacted communities that exist. This work is essential in understanding the true diversity of bacteria that inhabit the gastrointestinal microbiota on a global scale.