Biochemical studies and biological activities on L-glutaminase from rhizosphere soil  SAH2_CWMSG

Awad, Hassan M.; El-Deen, Azza M.Noor; Mostafa, El-Sayed E.; Hassabo, Amany A.

doi:10.4103/epj.epj_32_18

Biochemical studies and biological activities on L-glutaminase from rhizosphere soil SAH2_CWMSG

Authors

Abstract

Background and objective
L-glutaminase (L-GLUNase) is a potential anticancer enzyme that hydrolyzes amide bond of L-glutamine to give glutamate and ammonium ion. It is used as an antioxidant, a flavor enhancing agent and a biosensor for glutamine level measurement. The aim was to produce L-GLUNase in high yield from a promising local isolate for many pharmaceutical applications.
Materials and methods
A total of 20 isolates for their capacity of L-GLUNase production were screened. A potent L-GLUNase producer, SAH2_CWMSG isolate, was identified by phenotypic and phylogenetic analysis. L-GLUNase was purified using ammonium sulfate followed by gel filtration on Sephadex G-100. The purified L-GLUNase was characterized, and its application as an antimicrobial, anticancer, and antioxidant agent was investigated.
Results and conclusion
The phylogenetic analysis of SAH2_CWMSG strain confirmed that the SAH2_CWMSG strain was most similar to (99%). It produced L-GLUNase activity of 58 U/ml under shake flask submerged fermentation. The purified L-GLUNase has the molecular weight of 55 kDa and K and V value of 1.314 mmol/l and 95.24 μ Me/min, respectively. Of the various physiochemical parameters tested, pH 7.5 and temperature 40°C were optimal for the enzyme activity. On the contrary, 10 mmol/l of Mn showed a slight increase in L-GLUNase activity. A promising sp. fully identified as SAH2_CWMSG (Gen Bank ID: KU720627) is an efficient source of L-GLUNase production. Therefore, it can be potentially used as enzyme supplement, which has many industrial and pharmaceutical applications.

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