THERMAL DENATURATION OF α-AMYLASE FROM BACILLUS AMYLOLIQUEFACIENS IN THE PRESENCE OF SODIUM DODECYL SULPHATE*

Document Type : Research Note

Authors

Department of Biology, University of Shahrekord, P.O. Box: 115, Shahrekord, I. R. of Iran

Abstract

The thermal denaturation of α-Amylase from Bacillus amyloliquefaciens has been investigated in the presence and absence of sodium dodecyl sulphate (SDS) over the temperature range (293-373) K in 20 mM sodium phosphate buffer, pH 6.9, using temperature scanning spectroscopy. The presence of SDS caused the destabilization of α-Amylase resulting in a decrease in the temperature of unfolding with an increase in SDS concentration. The thermodynamic parameters for unfolding of α-Amylase were determined in terms of the two-state model, using the temperature dependence of the spectroscopic behaviour of the enzyme at 280 nm. The result from specific activity measurements in the presence of SDS is in conformity with the results from thermal studies.

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