 Richards had developed that cleavage system as a postdoc at the Carlsberg Laboratory in Copenhagen, Denmark, using purified ribonuclease protein that had been donated to Christian Anfinsen by the Armour Company and that Anfinsen shared with Richards and other researchers.Richards found that, when separated, S-protein and S-peptide had no RNase activity, but that the RNase enzymatic activity was restored when the parts were recombined in the test tube.In an autobiographical piece, Richards wrote that "this discovery came as a surprise to the scientific community at that time...