Ribo-attenuators: novel elements for reliable and modular riboswitch engineering

Abstract

Riboswitches are structural genetic regulatory elements that directly couple the sensing of small molecules to gene expression. They have considerable potential for applications throughout synthetic biology and bio-manufacturing as they are able to sense a wide range of small molecules and in response regulate gene expression. Despite over a decade of research they have yet to reach this considerable potential as they cannot be treated as modular components. This is due to several limitations including, sensitivity to changes in genetic context, low tunability and large degrees of variation. To overcome the associated difficulties with riboswitches, we have designed and introduced a novel genetic element called a Ribo-attenuator. This genetic element allows for predictable tuning, insulation from contextual changes and a reduction in expression variation. Ribo-attenuators allow riboswitches to be treated as a truly modular and tunable component, and thus increase their reliability for a wide range of applications.