Bacterial diets differentially alter lifespan and healthspan trajectories in C. elegans

Abstract

AbstractDiet is one of the more variable aspects in life due to the variety of options that organisms are exposed to in their natural habitats. In the laboratory,C. elegansare raised on bacterial monocultures, traditionally theE. coli Bstrain OP50, and spontaneously occurring microbial contaminants are removed to limit experimental variability because diet—including the presence of contaminants—can exert a potent influence over animal physiology. In order to diversify the menu available to cultureC. elegansin the lab, we have isolated and cultured three such microbes:Methylobacterium, Xanthomonas, andSphingomonas. The nutritional composition of these bacterial foods is unique, and when fed toC. elegans, can differentially alter multiple life history traits including development, reproduction, and metabolism. In light of the influence each food source has on specific physiological attributes, we comprehensively assessed the impact of these bacteria on animal health and devised a blueprint for utilizing different food combinations over the lifespan, in order to promote longevity. The expansion of the bacterial food options to use in the laboratory will provide a critical tool to better understand the complexities of bacterial diets and subsequent changes in physiology and gene expression.