- Expression, purification, crystallization and preliminary X-ray diffraction studies of human cathepsin F complexed with an irreversible vinyl sulfone inhibitor. Ho, J.D., Meltser, Y., Buggy, J.J., Palmer, J.T., Elrod, K.C., Chan, H., Mortara, K.D., Somoza, J.R. Acta Crystallogr. D Biol. Crystallogr. (2002)