Abstract: This article comprises detail information about L-asparaginase, encompassing topic such as various sources of L-asparaginase, mechanism and properties of L-asparaginase. Also describe the production, cultivation and purification of L-asparaginase along with information about the application of L-asparaginase. L-asparaginase catalyzes the conversion reaction to convert asparagine to aspartic acid and ammonia. Asparagine is a nutritional requirement for both normal and tumor cell. Present scenario has found that L-asparaginase has been found to be a best anti tumor or antileukemic agent. In the recent years this enzyme gained application in the field of clinical research pharmacologic and food industry. It has been characterized based on the enzyme assay principle hydrolyzing L-asparagine into L-aspartic acid and ammonia. It has been observed that eukaryotic microorganisms such as yeast and filamentous fungi have a potential for L-asparaginase production. L-asparaginase has been and is still one of the most lengthily studied therapeutic enzymes by scientist and researchers worldwide.
Abstract: L-asparaginase was extracted from pathogenic
Escherichia coli which was isolated from urinary tract infection
patients. L-asparaginase was purified 96-fold by ultrafiltration, ion
exchange and gel filtration giving 39.19% yield with final specific
activity of 178.57 IU/mg. L-asparaginase showed 138,356±1,000
Dalton molecular weight with 31024±100 Dalton molecular mass.
Kinetic properties of enzyme resulting 1.25×10-5 mM Km and
2.5×10-3 M/min Vmax. L-asparaginase showed a maximum activity
at pH 7.5 when incubated at 37 ºC for 30 min and illustrated its full
activity (100%) after 15 min incubation at 20-37 ºC, while 70% of its
activity was lost when incubated at 60 ºC. L-asparaginase showed
cytotoxicity to U937 cell line with IC50 0.5±0.19 IU/ml, and
selectivity index (SI=7.6) about 8 time higher selectivity over the
lymphocyte cells. Therefore, the local pathogenic E. coli strains may
be used as a source of high yield of L-asparaginase to produce anti
cancer agent with high selectivity.