Binds bis-(3'-5') cyclic diguanylic acid (c-di-GMP) (By similarity). Required for maximal cellulose synthesis, does not act as a protease on BcsA (PubMed:24942809). Produces much less cellulose, and the timing cellulose synthesis and structure of the fibers may be altered. Deletion can be complemented by the protein from S.typhimurium LT2 or E.coli, however the 'D-415' mutation in the E.coli protein does not complement (PubMed:24942809). Belongs to the BcsE family.