Tetrahydrofolate dehydrogenase (5,6,7,8-tetrahydrofolate:NADP+oxidoreductase, EC 184.108.40.206; formerly known as dihydrofolate reductase) from a subline of the L1210 lymphoma has been purified to apparent homogeneity with high recovery by simple steps using agarose to which the enzyme inhibitor amethopterin was coupled. A crude (NH4)2SO4precipitate was applied to a column of methotrexate-agarose which was washed with buffer containing NADPH to increase the binding of the enzyme to the column, and to elute non-enzyme protein. Buffer at high pH, containing dihydrofolate and high concentration of salt then eluted the enzyme together with some nucleic acid contaminants which were removed on a column of Sephadex G-75. © 1972.
Gauldie, J., & Hillcoat, B. L. (1972). Purification of tetrahydrofolate dehydrogenase by affinity chromatography. BBA - Enzymology, 268(1), 35–40. https://doi.org/10.1016/0005-2744(72)90194-5