Together with
Alfred Mirsky, Anson was the first to propose that conformational protein folding was a
reversible process. He later proposed that it was essentially a
two-state process, i.e., that the folded and unfolded states were well-defined thermodynamic states separated by a large activation energy barrier. He also was the first to note that the energy barrier typical of folding (5 kcal/mol, 20 kJ/lmol) was small compared to the absolute magnitudes of the energies and entropies involved (~100 kcal/mol, 400 kJ/mol) and, hence, proposed that energy and entropy were continuously traded off during the folding process. Anson moved to the
Rockefeller Institute in 1927, where he remained for fifteen years (1927–1942). He worked closely with
John H. Northrop. In 1937, Anson first purified and crystallized
carboxypeptidase A, a classic model system of protein science. ==
Advances in Protein Chemistry==