Production, purification and characterization of L-asparaginase from Streptomyces gulbargensis

ABSTRACT

L-asparaginase is an anti-neoplastic agent used in the lymphoblastic leukaemia chemotherapy. In the present study a novel strain, Streptomyces gulbargensis was explored for the production of extra-cellular L-asparaginase using groundnut cake extract. The optimum pH, temperature, inoculum size and agitation speed for enzyme production were pH 8.5, 40ºC, 1x10(8)spores/ml and 200 rev/min respectively. Maltose (0.5 percent) and L-asparagine (0.5 percent) proved to be the best carbon and nitrogen sources respectively. The enzyme was purified 82.12 fold and the apparent molecular weight of the enzyme was found to be 85 kDa. The optima pH and temperature for the enzyme were 9.0 and 40ºC respectively. The enzyme was more stable at the alkaline pH than at the acidic one and it retained 55 percent of the activity at 80ºC for 60 min.