Are there any chitosan-specific lectins?
Chitosan-specific lectins have been reported rarely and have never been purified and characterized in detail. 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. Recently, oligomers of galacturonic acid have been used for the same purpose but as their interaction with chitosan depends on the opposite charges of the two molecules, it is less specific and depending on pH. In any case, the distinction between chitin and chitosan requires double staining using chitosan- and chitin-specific probes.