Higher Order Structures of the Caseins: A Paradox?

Historically caseins were classified as random coils. Recent advances in the field of protein chemistry have produced a “New View” of protein structure. Casein structures are interpreted with regard to the latter theory and are now considered to be members of the class of proteins referred to as natively unfolded or molten globule. The caseins display the characteristics of this class of proteins as they react with each other using defined structural elements to form large, open, hydrated, flexible structures. These casein–casein interactions give the product, sodium caseinate, its reliable properties as a food ingredient. Overall, the concept that the caseins are both structured and flexible is explained using the architectural concepts of tensegrity.

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