Chitosan is a polymer that is currently made from crab and shrimp shells. It has interesting properties as a structurant for food and personal care products, but obtaining large quantities of pure material in a sustainable way is difficult. The aim of this collaboration is to genetically-engineer a bacteria to produce large quantities of relatively pure chitosan in fermenters. Not only would this provide the polymer from a non-animal source, it would also be free of the contaminants that can currently cause an allergic reaction unless removed, and would provide material from a sustainable source. Producing various types of chitosan via industrial fermentation using simple feedstocks would overcome the problems of sustainable and ethical production from crustaceans.