Trick and no treat: Carbohydrate preemption by commensal Enterobacteriaceae.

Have you ever caught family members eating the last piece of your Halloween candy? In this issue of Cell Host & Microbe, Osbelt et al. and Eberl et al. demonstrate how commensal Enterobacteriaceae preempt pathogen carbohydrate utilization, dependent upon the composition of the surrounding gut microbial community.