Protease A from cotton seeds. Isolation and purification of the enzyme
- 46 Downloads
Protease A has been isolated in the homogeneous state from dormant seeds of cotton plants of the Tashkent-I variety. A scheme is proposed for the isolation and purification of the enzyme which includes the following stages: extraction of the defatted seeds with 0.1 M phosphate buffer, pH 7.4; precipitation of the protein with ammonium sulfate at 60% saturation; desalting by dialysis; and ionexchange chromatography on a column containing CM- and DEAE-celluloses. The molecular weight of the enzyme has been determined as 60,000. The enzyme efficiently hydrolyzes azocasein and the 7S and 11S reserve proteins of cotton seeds. Its maximum activity appears at pH 6.4–7.4 and a temperature of 35–40°C; it is not activated by sulfhydryl reagents and loses its activity in the presence of diisopropyl phosphorofluoridate. The assumption is made that protease A belongs to the serine type of trypsin-like proteases.
KeywordsAmmonium Sulfate Dormant Seed Cotton Plant Cotton Seed Azocasein
Unable to display preview. Download preview PDF.
- 3.M. A. Kuchenkova, N. L. Ovchinnikova, and P. Kh. Yuldashev, Khim. Prir. Soedin., 4 (1973).Google Scholar
- 4.G. M. Podgornov, M. A. Kuchenkova, and P. Kh. Yuldashev, Khim. Prir. Soedin., 1 (1974).Google Scholar
- 5.G. L. Mezhlum'yan, M. A. Kuchenkova, and P. Kh. Yuldashev, Khim. Prir. Soedin., 275 (1985).Google Scholar
- 6.G. Yu. Azhitskii, G. V. Troitskii, and K. D. Malyi, Lab. Delo, 12 (1975).Google Scholar
- 7.O. Warburg and W. Christian, Biochem. Z.,310, 388 (1941).Google Scholar
- 9.E. D. Kaverzneva, Prikl. Biochem. Mikrobiol., No. 2, 225 (1971).Google Scholar