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Medical Term:


Pronunciation: kol'la-jen


The major protein (comprising over half of that in mammals) of the white fibers of connective tissue, cartilage, and bone; insoluble in water but can be altered to easily digestible, soluble gelatins by boiling in water, dilute acids, or alkalis. It is high in glycyl, l-alanyl, l-prolyl, and l-4-hydroxyprolyl residues, but is low in sulfur and has no l-tryptophanyl residues. It comprises a family of genetically distinct molecules all of which have a unique triple helix configuration of three polypeptide subunits known as a-chains; at least 18 types of collagen have been identified, each with a different polypeptide chain.

Synonym(s): ossein, osseine, ostein, osteine

[G. koila, glue, + -gen, producing]

See Also: collagen fiber

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