Tags: Protein.
The extracellular polysaccharide colanic acid (CA) is produced by species of the family Enterobacteriaceae. In Escherichia coli (strain K12) the CA cluster comprises 19 genes. The wzx gene encodes a protein with multiple transmembrane segments that may function in export of the CA repeat unit from the cytoplasm into the periplasm in a process analogous to O-unit export. The CA gene clusters may be involved in the export of polysaccharide from the cell.