The gut microbiota is intricately linked to various facets of human health. Owing to the accelerated process of urbanization taking place globally, there are consequential modifications in our gastrointestinal microbiomes due to transformations in dietary habits and lifestyles. Although existing studies endeavor scrutinize the disparities in taxonomic composition and functional potential of the gut microbiota among populations with varying degrees of urbanization and diverse lifestyle, a vast majority of these populations, especially the ethnic groups living in remote rural areas, remains under-explored. Moreover, characteristic of urbanization varies among nations and corresponds to the distinct natural and cultural history of the populations. The difference of urbanization will probably lead to different changes of the gut microbiota, where more studies on different ethnicities are clearly warranted.
To facilitate the large-scale metagenomic studies on different populations, especially those living in remote areas without well-constructed transport infrastructures, I developed an N-octylpyridinium bromide (NOPB) based reagent and assessed its performance in fecal sample storage and transportation systematically. The results proved that the reagent could stabilize fecal samples for shotgun metagenomic sequencing at room temperature for up to seven days, which is usually enough for transferring collected samples to laboratories equipped with freezers.
By the help of this NOPB-based stabilizer reagent, I collected fecal samples from people of six different ethnic groups from Yunnan, China. Participants live in the capital city of the province follow the urbanized lifestyle, whereas those living in remote rural villages adhere to distinct traditional lifestyles. A novel microbial gene catalogue consisting of 11,423,467 genes was constructed using these samples, and 1,062 MGSs were further identified. The abundant unknown genes and poorly annotated MGSs in the catalogue shed light on the unrecovered diversity of the gut microbiota among populations. The results also suggested that the urbanization may change human gut microbiota in different ways among populations, rather than in a simple, world-wide uniform manner.