I don't think it should matter if protein is cooked or not. Some of the larger structures of how the proteins "stick together" (quaternary & tertiary structure, basically, how the protein folds) will be broken, but the proteins should still have the same old chain of amino acids.
I mean, if cooked beef infected with Mad Cow's Disease (a PRION, which is an infectious protein) can still survive and infect you, then I think all other protein would be the same.