Despite their essential role in microbial metabolism, transport processes across cellular membranes are a relatively neglected area of research in biotechnology. This often results in inefficient bioconversions, product accumulation and potential cytotoxicity, as the cell membrane is mostly impermeable to chemical compounds without specialized transport proteins. Aquaglyceroporins (AQGPs) are channels that transport small, non-charged, polar molecules in a selective manner, and with no energetic costs. By engineering their activity, channels with the desired properties can be obtained to improve a wide array of processes in industrial biotechnology. This project will embrace the potential for engineering of AQGPs, the understanding of their determinants of selectivity and natural variation for implementation in two major work packages: boosting selective export of the bioplastic monomer 1,3-propanediol; and improving import and bioconversion rates of methanol, a renewable abiotic substrate for biotechnology. In order to screen both large synthetic libraries and natural variants, a flexible and scalable screening method will be used, employing transcriptional biosensors. Success in this project will not only deliver tangible results for specific industrial biotechnology processes, but will also open the door towards deploying AQGPs in a wide array of bioconversions involving small polar molecules.