Immunochemical studies of the cellulose synthase complex inAcetobacter xylinum

An immunochemical method was used to analyse the 83 and 93 Kd polypeptides of cellulose synthase fromAcetobacter xylinum.Polyclonal antibodies were raised against the LDS-PAGE-fractionated 83 and 93 Kd polypeptides isolated fromA. xylinum.Using these antibodies, the 83 and 93 Kd polypeptides were localized in the different fractions during purification of cellulose synthase, and the ratio of these two polypeptides was determined to be 11. A differential solubilization of the 83 and 93 Kd polypeptides from the cell strongly suggested that the mechanism by which these two polypeptides originate from a singleacsABgene product (Saxenaet al.,1994) must be via a post-translational cleavage. The results of trypsin treatment of the membrane fraction used in the purification of cellulose synthase were analysed to determine the fate of these two polypeptides and their relationship to the enzyme activity.