mucins

n. nitrogenous substance present in mucus secretions

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.
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Mucin /mu·cin/ 1. any of a group of protein-containing glycoconjugates with high sialic acid or sulfated polysaccharide content that compose the [more]Mucins - Community and Resources