Patent ID: 7932053

Claim:
A method for the in vitro production of a modified collagenous protein, comprising (a) unfolding folded collagen α-chains comprising an association domain to obtain unfolded collagen α-chains; (b) modifying the unfolded α-chains by adding modifying enzymes; and (c) folding the modified α-chains into a triple helical structure; wherein none of steps (a)-(c) is performed intracellularly; and wherein said association domains comprise one or more interchain crosslinks linking the collagen α-chains together; or wherein the association domains comprise amino acid sequences that reassociate after unfolding; or wherein the association domains comprise amino sequences by which the collagen α-chains remain bound to each other during unfolding of the remainder of the collagen α-chains; and wherein said modifying enzymes modify the amino acid side chains of the α-chains.