Characterization of functional intermediates of endoglucanase from Aspergillus aculeatus during urea and guanidine hydrochloride unfolding.

Naika, Gajendra Sunnamada and Purnima Kaul, Tiku (2010) Characterization of functional intermediates of endoglucanase from Aspergillus aculeatus during urea and guanidine hydrochloride unfolding. Carbohydrate Research, 345 (11). 1627-1631 . ISSN 0008-6215

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Abstract

Low concentrations of urea and GuHCl (2 M) enhanced the activity of endoglucanase (EC 3.1.2.4) from Aspergillus aculeatus by 2.3- and 1.9-fold, respectively. The Km values for controls, in the presence of 2 M urea and GuHCl, were found to be 2.4 ± 0.2 × 10−8 mol L−1, 1.4 ± 0.2 × 10−8 mol L−1, and 1.6 ± 0.2 × 10−8 mol L−1, respectively. The dissociation constant (Kd) showed changes in the affinity of the enzyme for the substrate with increases in the Kcat suggesting an increased turnover number in the presence of urea and GuHCl. Fluorescence studies showed changes in the microenvironment of the protein. The increase in the activity of this intermediate state was due to conformational changes accompanied by increased flexibility at the active site.

Item Type:	Article
Uncontrolled Keywords:	Endoglucanase; Urea; GuHCl; Conformation
Subjects:	600 Technology > 08 Food technology > 29 Microbiological food > 02 Fungi 600 Technology > 08 Food technology > 16 Nutritive value > 05 Enzymes
Divisions:	Protein Chemistry and Technology
Depositing User:	Users 197 not found.
Date Deposited:	13 Oct 2010 10:47
Last Modified:	28 Dec 2016 11:12
URI:	http://ir.cftri.res.in/id/eprint/9750

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