A scalable method to purify reflectins from inclusion bodies

Structural proteins are an attractive inspiration for functional biobased materials. In nature, cephalopods skin colour modulation is related to the dynamic self-assembly of a family of structural proteins known as reflectins. To fully reach their potential as engineered bio-based materials, reflectins need to be produced by biotechno-logical means. One of the challenges is associated with establishing and optimizing reflectin purification pro-cesses to achieve the highest yield and productivity. Here, we studied purification strategies for two reflectin sequences from different organisms which were recombinantly expressed in a bacterial host at laboratory scale. Reflectins purification was then assessed by two chromatographic and one non-chromatographic methods. Methods were compared considering final purity and yield, productivity, cost and sustainability. The non-chromatographic method based on inclusion bodies washing presented the most promising results (protein pu-rity > 90% and purification yields up to 88%). Our results contribute to define bioprocessing strategies to address the vision of biodegradable and sustainable protein-based materials.