(284j) S. Oneidensis As a Living Electrode for Controlled Radical Polymerization

Bacteria produce a variety of soft materials, but they are limited in their structure and function. A synthetic system in which the power of bacterial engineering is combined with traditional organometallic catalysis could pave new avenues to polymer synthesis. Here we demonstrate that the electroactive bacteria Shewanella oneidensis can control the activity of a transitional-metal catalyst in atom-transfer radical polymerization (ATRP) through extracellular electron transport (EET) machinery. This polymerization features characteristics of controlled radical polymerization, such as first-order kinetics, narrow molecular weight distribution and block-polymer synthesis. Catalyst performance and polymer microstructure were a strong function of bacterial metabolism, specific electron transport machinery, and catalyst design. Moreover, different bio-renewable and bio-friendly energy sources, such as lactate, glucose, pyruvate and xylose, could be utilized to control the rate of polymerization process. Overall, our results demonstrate that targeting biological electron transport pathways may combine the advantages of metabolic engineering with traditional polymer synthesis.