Structural and functional determinants of Mucor miehei protease. II. Circular dichroic studies on the native and periodate-oxidized enzyme

Abstract

Structural investigations of the glycoprotein, Mucor miehei protease, by CD, suggested that the native enzyme contains a significant amount of β structure and little, if any, α-helix within the pH range 2.5 to 7.0. Comparison of the CD spectra of the protease with those of other proteins suggested somewhat distorted β arrangements. Exposure of the enzyme to periodate oxidation resulted in a rapid loss of about 40% of the carbohydrate but no detectable change in structure or enzymatic activity. The remainder of the carbohydrate was resistant to further oxidation; any additional decrease being associated with changes in structure and loss of proteolytic activity.