Production of cellulose has been initially observed in Acetobacter xylinum. Recent studies though have shown that besides thin aggregative fimbriae, the second component of the extracellular matrix of the multicellular morphotype (rdar) of Salmonella typhimurium and Escherichia coli is cellulose. BcsC is a member of this cellulose synthase operon composed also by BcsA, BcsB and BcsD genes. Mutants in the BcsC and BcsD genes were impaired in cellulose production in vivo, even though they had the capacity to make all the necessary metabolic precursors and cyclic diguanylic acid, the activator of cellulose synthase, and exhibit cellulose synthase activity in vitro. Recently, a proteomics analysis of Erwinia chrysanthemi, revealed that BcsC is located in the outer membrane. The postulated ß-barrel domain is located in the C-terminal of the protein and probably serves as a membrane anchoring region or a channel for cellulose export. Other domains are also found in the rest of the protein, including several tetratricopeptide repeat (TPR) domains, responsible for protein-protein interactions.

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