Guild-level response of the gut microbiota to isocaloric time-restricted feeding in high-fat diet-fed mice

Time-restricted feeding (TRF) during the active phase protects against high-fat diet (HFD)-induced obesity, and its impact on gut microbiota has been previously investigated using bacterial taxa as functional units. However, in the gut ecosystem, bacteria from different taxonomic backgrounds form coherent functional groups called guilds, whose members exhibit co-abundant behavior. Thirty-five co-abundance groups (CAGs), clustered from 297 prevalent amplicon sequence variants (ASVs), showed greater concordance with beta-diversity plots based on all 1131 ASVs than the 130 classifiable genera, leading to a significantly improved preservation of community-level information. TRF-enriched CAGs positively correlated with metabolic improvement, while TRF-reduced CAGs negatively correlated. TRF restored the diurnal rhythm of most of these key CAGs. Novel ASVs, unclassifiable at the genus level, were identified in these key CAGs. Overall, this suggests that the key bacterial guilds may mediate the beneficial metabolic effects of TRF through the restoration of diurnal oscillation.