Current concepts of the structure and nature of mammalian salivary mucous glycoproteins

Abstract

The visco-elastic properties of salivary secretions are due to high molecular-weight glycoproteins, known as mucins. Mucins are composed of numerous oligosaccharide side-chains O-glycosidically linked through 2-acetamido-2-deoxy-alpha-D-galactose to the hydroxyl groups of seryl and threonyl residues of the protein core; on the average, every fourth amino acid residue is involved in such a bond. This work conveys their isolation and purification, compiles the compositional analysis of several mammalian submaxillary and sublingual mucins; defines the conditions of the alkaline beta-elimination reaction, its mechanism, and importance in structural studies of glycoprotens, and briefly discusses the influence of stimuli on mucous secretions, as well as biosynthesis, structural diversity, and physiological role of salivary mucous glycoproteins.

Candida albicans Mucin Msb2 Is a Broad-Range Protectant against Antimicrobial Peptides

“…Human mucins, like the C. albicans Msb2 mucin, are highly O-glycosylated proteins, which conceptually could compete for the binding of AMPs. As a model for human mucin, we assayed binding of 5-FAM-LL-37 to porcine gastric mucin, which is structurally similar to human mucin (20,26). MST measurements revealed a much lower affinity of binding to porcine mucin (K D ϭ 876 nm) than to C. albicans Msb2* (Table 2).…”

Characterization of the high Mr glycoprotein (gP300) of equine herpesvirus type 1 as a novel glycoprotein with extensive O-linked carbohydrate

“…Amongst mammalian systems, proteins characterized with high levels of O-glycosylation are the mucins, which contain numerous short carbohydrate chains present as O-linkages (Herp et al, 1979). The low Mr of much of the carbohydrate released from gp300, together with the high Mr of the protein, could indicate a mucin-like structure.…”

Multispecies communities: interspecies interactions influence growth on saliva as sole nutritional source

“…Hog gastric mucin has been used as a model substrate for saliva because this mucin possesses the highest similarity in oligosaccharide structure with human salivary mucin [8]. The idea that different bacterial species possess individual enzymatic activities that act in succession was explore in experiments using hog gastric mucin as the sole source of carbohydrate for growth and synergistic degradation of mucin was observed by van der Hoeven and Camp [9].…”