A reliable clock for your microbiome

The microbiome is a treasure trove of information about human health and disease, but getting it to reveal its secrets is challenging. A new genetic 'repressilator' circuit acts like a clock that tracks how bacterial growth changes over time with single-cell precision. This tool allows scientists to noninvasively study the dynamics of the microbiome, and also unlocks the potential for complex, synthetic-biology-based diagnostics and therapeutics for the human gut.