Methods for separation and deglycosylation of mucin subunits

Mucins (density 1.35-1.50 g/ml) prepared from human cervical, gastric, respiratory, and salivary secretions were reduced and alkylated to generate reduced mucin subunits. These subunits were separated into different populations analytically by using agarose gel electrophoresis and preparatively by using anion-exchange chromatography. Both techniques separate the molecules primarily on the basis of their inherent charge. A procedure has been developed for the efficient deglycosylation of small amounts of these reduced mucin subunits immobilized on polyvinylidene difluoride. The combination of these procedures has allowed the isolation and identification of glycoforms of a specific mucin gene product in a respiratory mucous secretion.