3.F.3.  The Proton-driven Beta-Lactam Antibiotic Translocon (P-BLT) Family

A simple molecular system to actively accumulate and degrade pollutants could be a bionanoreactor composed of a liposome or polymersome scaffold combined with energizing - (e.g., light-driven proton pump), transporting- (e.g., proton-driven transporter) and degrading modules (e.g., enzyme) (Stauffer et al. 2021). The engineering of a transport module specific for β-lactam antibiotics was developed. They had previously solved the crystal structure of a bacterial peptide transporter, which allowed them  to improve the affinity for certain β-lactam antibiotics using structure-based mutagenesis combined with a bacterial uptake assay. They identified specific mutations, which enhanced the affinity of the transporter for antibiotics containing certain structural features. Screening of potential compounds allowed for the identification of a β-lactam antibiotic ligand with relatively high affinity. Transport of antibiotics was evaluated using a solid-supported membrane electrophysiology assay. Thus, Stauffer et al. 2021 have engineered a proton-driven β-lactam antibiotic translocation module.