From sporulation to village differentiation: The shaping of the social microbiome over rural-to-urban lifestyle transition in IndonesiaOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study examined how the gut microbiome changes across a rural-to-urban lifestyle transition in Indonesia. The researchers assembled metagenome-assembled genomes to characterize species and subspecies diversity within these communities. They also investigated how bacterial physiology, specifically sporulation capacity, relates to how widespread or restricted a given microbial taxon is across villages. Finally, they assessed whether diet variation between communities versus within communities better predicts overall microbiome composition.
Who was studied?
The dataset comes from 116 Indonesians whose lifestyles span transitional hunter-gatherer, rural agricultural, and urban populations. This sampling directly addresses a gap in microbiome research, since existing datasets are heavily biased toward Western urban cohorts and Southeast Asia has been especially under-represented. From these 116 individuals, the team assembled 11,070 metagenome-assembled genomes for analysis.
What were the most important findings?
The researchers identified 1,304 species and 3,258 subspecies, revealing substantial novelty at both the species level (15%) and the subspecies level (50%). Novel taxa tended to be rare, often specific to a single village, and depleted in sporulation genes, linking bacterial physiology to transmission patterns, prevalence, and the likelihood of prior discovery. Clear rural-to-urban clines emerged across multiple levels of biological organization, from individual species abundance to overall microbiome composition and diversity. Diet variation between communities, but not variation within a community, strongly predicted microbiome composition.
What are the greatest implications of this study?
The findings suggest that microbiome divergence across lifestyles is shaped primarily by community-level factors rather than individual-level differences in diet. The link between sporulation genes and village-specific, rarely detected taxa highlights how bacterial physiology influences transmission and the chances a species has been previously characterized. This work underscores the need to expand microbiome sampling beyond Western urban populations to capture the full scope of human microbiome diversity and biogeography. It also demonstrates that lifestyle transition, population structure, and bacterial physiology jointly shape microbiome variation at the scale of human communities.