Collagen Type VI, human

Collagen type VI is found as 5-10 nm diameter microfibrils (periodicity 100 nm) e.g. in placenta, skin, cartilage and cornea. Collagens consist of a family of highly specialized glycoproteins of which at least 16 genetically distinct types are known to date. The basal unit of a collagen molecule consists of a triple-helical structure formed by 3 alpha-chains. Predominant amino acids are glycine, proline and hydroxproline. Regularly also lysines and hydroxylysines occur, which are responsible for cross-linkage and glycosylation of the protein chains. Different composition of alpha-chains and different glycosylation contribute to the high variability of collagens in different tissues and organs. Human collagen type VI 100%, human collagen type I, II, III, IV and V <0.1%; human elastin and human laminin <0.1%; human fibronectin < 1% (RIA at 1:10.000 dilution).