Are there chitosan binding proteins/modules/domains?
Unlike chitin binding modules and proteins which are widespread, chitosan binding modules and chitosan binding proteins have rarely been described. Some bacterial chitosanases possess discoidin-like domains which have been shown to specifically bind to chitosan. In some plants, chitosan-specific lectins have been described but not purified and characterized, which have also been suggested to act as chitosan receptors, but with no experimental evidence supporting this claim. Fusing an inactivated chitosanase with fluorescent proteins such as GFP or YFP has yielded artificial chitosan-specific 'lectins' which can be used for the cytochemical detection of chitosan.