Microbial nitrogen limitation in the mammalian large intestine

Resource limitation is a fundamental factor governing the composition and function of ecological communities. However, the role of resource supply in structuring the intestinal microbiome has not been established and represents a challenge for mammals that rely on microbial symbionts for digestion: too little supply might starve the microbiome while too much supply might starve the host. We assessed microbial nitrogen limitation by manipulating dietary protein availability then measured microbial utilization of nitrogen from host secretions and diet. Data include 16S rRNA gene amplicon sequencing for fecal samples from 2 week protein diet intervention to assess microbial nitrogen limitation as well as small intestine and large intestine samples from mice treated with 15N tracers via spirulina chow or injected threonine.