Plastic degradation is mediated via a laccase protein. As such, we will be using an enzymatic activity assay to determine that the laccase enzyme is expressed. Laccase catalyses the oxidation of syringaldazine, a reaction that exhibits an observable OD change at 530nm. A sample of syringaldazine can be used as a blank in a spectrophotometer, against a sample containing syringaldazine and our laccase sample, allowing the rate of oxidation to be measured, and hence the enzymatic activity of laccase.
In order to determine the effectiveness of laccase in degrading plastic, we will expose strips of various types of plastic to the laccase expressing bacteria, before viewing the strips under a scanning electron microscope. This will allow us to compare the pitting in plastic samples treated with laccase, to the untreated samples, allowing us to determine the extent of plastic degradation.