Ethylenediaminetetraacetic acid enhances structural stability and thermotolerance of recombinant cyclomaltodextrinase from Geobacillus thermopakistaniensis at higher temperatures.

Abstract

Abstract Ethylenediaminetetraacetic acid (EDTA), a chelating agent, has shown the ability to enhance the thermostability of cyclomaltodextrinase from Geobacillus thermopakistaniensis (CDaseGt). There was a 5-fold and 3-fold enhancement in the half-life of the enzyme at 70 and 75°C, respectively, when purified in the presence of EDTA. To further investigate, recombinant CDaseGt was subjected to molecular-level characterization using various techniques including circular dichroism spectroscopy, fluorescence spectroscopy, and fourier-transform infrared spectroscopy in the presence and absence of EDTA. Presence of EDTA caused several changes in the secondary structure of CDaseGt, specifically in terms of chirality and relocation of hydrophobic patches. No disturbance in the functional groups were observed with the addition of EDTA. The affinity analysis displayed a favorable binding and attractive electrostatic interactions between CDaseGt and EDTA. These findings provide insights into CDaseGt−EDTA interactions for better understanding of the structure-function relationship. The findings from this study contribute to our understanding of enzyme stability and provide valuable information for the development of more efficient and stable enzymes with a wide range of practical applications.