DRP004825
Elucidation of the mechanisms of chitosan-like bioflocculant production  by Citrobacter strains and its higher production.
In the genus Citrobacter, at least four species, C. freundii, C.  braaki, C. youngae, and C. werkmanni, can produce a chitosan-like  polysaccharide consisting of N-acetylglucosamine and glucosamine from  acetic acid in the cultures as a soluble form (Appl. Microbiol.  Biotechnol., 97, 9569-9577, 2013). It is a polycationic polymer and can  be used as an efficient flocculant for water treatment. The aim of this  project is to produce this polysaccharide in a large quantity for the  industrial use such as sludge dewatering and metal removal and  recovery. For this purpose, we are trying to breed higher-producing  strains by metabolic engineering based on the genome sequence.