Bacteria to Control Electron Transport Altering the Synthesis of Non-native Biopolymer

The use of bacteria as catalysts for radical polymerisations of synthetic monomers has recently been established. However, the role that transplasma membrane electron transport (tPMET) plays in modulating these processes is not well understood. We sort to study this by genetic engineering of a part of a tPMET system NapC in E. coli and show this altered the rate of extracellular electron transfer and caused an effect on cell-mediated polymerisation using a model monomer. A plasmid with arabinose inducible PBAD promoters were shown to upregulate NapC protein upon arabinose induction at total arabinose concentrations of 0.0018% and 0.18%. These clones (E. coli (IP_0.0018%) and E. coli (IP_0.18%), respectively) were used in Fe atom transfer radical polymerization (ATRP), revealing faster polymerization rates than cultures containing suppressed or empty plasmids (E. coli (IP_S) and E. coli(E), respectively). These results lead to the hypothesis that EET (Extracellular Electron Transfer) mechanisms in part modulate rates of ATRP iron-mediated cell instructed polymerizations.