Low molecular mass products of depolymerization of purified mucin - attempts at isolation and characterization

Samples of crude mucin were incubated at room temperature for 48 and 96 h in a sodium azide containing buffer, pH 7.0. Then each sample was purified, reduced and alkylated with iodo[^14C]acetamide. Electrophoretic analysis demonstrated that radioactivity was incorporated into the mucin subunits and proteins of 100 and 140 kDa. The results of our experiments suggest that the released proteins can be a part of mucin molecule, cleaved by proteolysis and reduction of disulfide bridges.