Mucins are a family of large, heavily glycosylated proteins. Although some mucins are membrane bound due to the presence of a hydrophobic membrane-spanning domain that favors retention in the plasma membrane, the concentration here is on those mucins that are secreted on mucosal surfaces and saliva. A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Drawing of a cell membrane A component of every biological cell, the selectively permeable cell membrane (or plasma membrane or plasmalemma) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell. ... In chemistry, hydrophobic or lipophilic species, or hydrophobes, tend to be electrically neutral and nonpolar, and thus prefer other neutral and nonpolar solvents or molecular environments. ... Drawing of a cell membrane A component of every biological cell, the cell membrane (or plasma membrane) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell. ... In animals, saliva is produced in and secreted from the salivary glands. ...

Mucin genes encode mucin monomers that are synthesized as rod-shaped apomucin cores that are post-translationally modified by exceptionally abundant glycosylation. Two distinctly different regions are found in mature mucins: This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... In chemistry, a monomer (from Greek mono one and meros part) is a small molecule that may become chemically bonded to other monomers to form a polymer. ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ...

• The amino- and carboxy-terminal regions are very lightly glycosylated, but rich in cysteines, which are likely involved in establishing disulfide linkages within and among mucin monomers.

• A large central region formed of multiple tandem repeats of 10 to 80 residue sequences in which up to half of the amino acids are serine or threonine. This area becomes saturated with hundreds of O-linked oligosaccharides. N-linked oligosaccharides are also found on mucins, but much less abundantly.

The dense "sugar coating" of mucins gives them considerable water-holding capacity and also makes them resistant to proteolysis, which may be important in maintaining mucosal barriers. Generic Structure of a Mucin Monomer File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Cysteine is a naturally occurring hydrophobic amino acid which has a sulfhydryl group and is found in most proteins, however only in small quantities. ... In chemistry, a disulfide is an ion formed by sulfur atoms. ... In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ... Serine is one of the 20 natural amino acids. ... Threonine is one of the 20 natural amino acids. ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ... The term “oligosaccharide” refers to a short chain of sugar molecules (“oligo” means “few” and “saccharide” means “sugar. ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ... The term “oligosaccharide” refers to a short chain of sugar molecules (“oligo” means “few” and “saccharide” means “sugar. ... A hygroscopic or hydroscopic substance is a substance that absorbs water readily from its surroundings. ... Proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion. ... The mucous membranes (or mucosae; singular: mucosa) are linings of ectodermic origin, covered in epithelium, and are involved in absorption and secretion. ...

Mucins are secreted as massive aggregates by prostaglandins with molecular masses of roughly 1 to 10 million Da. Within these aggregates, monomers are linked to one another mostly by non-covalent interactions, although intermolecular disulfide bonds may also play a role in this process. Look up Aggregate on Wiktionary, the free dictionary The term aggregate may refer to— in communication, to collect messages from multiple sources for presentation together, as in an RSS (file format) aggregator. ... A prostaglandin is any member of a group of lipid compounds that are derived from fatty acids and have important functions in the animal body. ... Look up Aggregate on Wiktionary, the free dictionary The term aggregate may refer to— in communication, to collect messages from multiple sources for presentation together, as in an RSS (file format) aggregator. ... In chemistry, a monomer (from Greek mono one and meros part) is a small molecule that may become chemically bonded to other monomers to form a polymer. ... Covalent bonding is a form of chemical bonding characterized by the sharing of one or more pairs of electrons between atoms, in order to produce a mutual attraction, which holds the resultant molecule together. ... In chemistry, a disulfide is an ion formed by sulfur atoms. ...