[feed] Atom [feed] RSS 1.0 [feed] RSS 2.0

Purification, characterization and kinetic properties of extracellular L-asparaginase produced by Cladosporium sp.

Mohan Kumar, N. S. and Manonmani, H. K. (2013) Purification, characterization and kinetic properties of extracellular L-asparaginase produced by Cladosporium sp. World Journal of Microbiology and Biotechnology, 29 (4). pp. 577-587.

[img] PDF
World Journal of Microbiology and Biotechnology (2012).pdf - Published Version
Restricted to Registered users only

Download (602kB)

Abstract

L-asparaginase from Cladosporium sp. grown on wheat bran by SSF was purified. Enzyme appeared to be a trimer with homodimer of 37 kDa and another 47 kDa amounting to total mass of 121 kDa as estimated by SDSPAGE and 120 kDa on gel filtration column. The optimum temperature and pH of the enzyme were 30 �C and 6.3, respectively with Vmax of 4.44 lmol/mL/min and Km of 0.1 M. Substrate specificity studies indicated that, L-asparaginase has greater affinity towards L-asparagine with substrate hydrolysis efficiency (Vmax/Km ratio) eightfold higher than that of L-glutamine. L-asparaginase activity in presence of thiols studied showed decrease in Vmax and increase in Km, indicating nonessential mode of inactivation. Among the thiols tested, b-mercaptomethanol, exerted inhibitory effect, suggesting a critical role of disulphide linkages in maintaining a suitable conformation of the enzyme. Metal ions such as Ca2?, Co2?, Cu2?, Mg2?, Na?, K? and Zn2? significantly affected enzyme activity whereas presence of Fe3?, Pb2 ? and KI stimulated the activity. Detergents studied also enhanced L-asparaginase activity. In-vitro half-life of purified L-asparaginase in mammalian blood serum was 93.69 h. The enzyme inhibited acrylamide formation in potato chips by 96 % making it a potential candidate for food industry to reduce acrylamide content in starchy fried food commodities.

Item Type: Article
Uncontrolled Keywords: Cladosporium sp. � Purification � L-asparaginase � Inhibition kinetics � Acrylamide reduction
Subjects: 600 Technology > 05 Chemical engineering > 04 Fermentation Technology
600 Technology > 08 Food technology > 16 Nutritive value > 05 Enzymes
Divisions: Fermentation Technology and Bioengineering
Depositing User: Food Sci. & Technol. Information Services
Date Deposited: 01 Jan 2013 08:45
Last Modified: 22 Dec 2016 13:11
URI: http://ir.cftri.com/id/eprint/11082

Actions (login required)

View Item View Item