Comparing the biochemical activity of Methylobacterium extorquens AM1 grown in separate medias with La3+ and Ca2+ as cofactorsof methanol dehydrogenase (MDH). Recent studies have demonstrated that some enzymes in bacteria isolated from lanthanide-richareas use lanthanides as metal cofactors in place of more common metals like calcium and that these lanthanide-enzymes haveenhanced catalytic properties. The bioelectrocatalytic activity of MDH from M. extorquens grown in La3+ rich media is compared toMDH from M. extorquens grown in typical Ca2+ rich media. A coupled assay of phenazine methosulfate-dichlorophenolindophenol isperformed to determine the enzyme activity. Different redox polymer films have been tested to determine the optimal film toimmobilize the bacteria while still allowing bioelectrocatalysis to be performed. The bioelectrochemical activities from these bacteriahave not previously been compared. If La3+ grown M. extorquens has higher bioelectrochemical activity than Ca2+ grown M.extorquens, then improved biofuel cells and sensors can be created.
