Enzyme and Microbial Technology, Vol.98, 9-17, 2017
In vitro screening and in silico validation revealed key microbes for higher production of significant therapeutic enzyme L-asparaginase
L-asparaginase is an enzyme of medical prominence and reputable as a chemotherapeutic agent. It also has immense potential to cure autoimmune and infectious diseases. The vast application of this enzyme in healthcare sector increases its market demand. However, presently the huge market demand is not achieved completely. This serves the basis to explore better producer microbial strains to bridge the gap between huge demand and supply of this therapeutic enzyme. The present study deals with the successful screening of potent microorganisms producing L-asparaginase. 47 microorganisms were screened including bacteria, fungi, and yeasts. Among all, Penicillium lilacinum showed the highest enzyme activity i.e., 39.67 IU/ml. Shigella flexneri has 23.21 IU/ml of enzyme activity (highest among all the bacterial strain tested). Further, the 3-D structure of L-asparaginase from higher producer strains was developed and validated in silico for its activity. L-asparagine (substrate for L-asparaginase) was docked inside the binding pocket of P. lilacinum and S. flexneri. Docking score for the most common substrate L-asparagine is 6.188 (P. lilacinum), 5.576 (S. flexneri) which is quite good. Moreover, the chemical property of the binding pocket revealed that amino acid residues Phe 243, Gln 260, Gly 365, Asp 386 in P. lilacinum and residues Asp 181, Thr 318, Asn 320 in S. flexneri have an important role in H-bonding. The in silico results supports and strengthen the wet lab results. The outcome obtained motivates to take the present study result from lab to industry for the economic/massive production of this enzyme for the diverse therapeutic application. (C) 2016 Elsevier Inc. All rights reserved.
Keywords:L-asparaginase;Higher producer strains;In vitro screening;In silico validation;Therapeutics