The expression of protease gene fromVirgobacillus natechei marine and its Immobilization on Nanocomposite

The expression of protease gene fromVirgobacillus natechei marine and its Immobilization on Nanocomposite

Protein hydrolysis of aquatic waste is an appropriate and economic strategy to obtain valuable products. In recent years, according to the attention of researchers to using green technology in the hydrolysis of proteins that have been obtained from aquatic wastes, protease enzymes have been introduced to this industry. But since the proteases that have been produced from natural resources are not economical for mass production, using new methods, including genetic engineering, to solve this problem is necessary. In the present study, in order to produce a recombinant enzyme after transferring the synthesized gene of protease into the vector PET28a, the created structure was transferred to the E. coli BL21 (DE3) host. After the process of enzyme expression and its purification, in order to make practical use of the produced enzyme, the stabilization of the enzyme was carried out on the synthesized nanocomposite supports made from aminographene and chitosan. The size, structure, and morphology of this nanocomposite were studied before and after immobilization of the enzyme using a field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and dynamic light scattering (DLS). The physical, kinetic, and thermodynamic parameters of free and immobilized enzymes were measured. The results showed that enzyme immobilization increased the optimum temperature to 10°C, but the optimum pH of 8 did not change. The stability of the immobilized enzyme was enhanced at high temperatures, critical pH (3 and 12), and long-term storage. Stabilization also changed the kinetic parameters (increasing Km, decreasing kcat/km, and Vmax). The results of the present study are a valuable step in marian biotechnology through the enzyme production of the marine bacteria gene and its stabilization using several combined technologies. It appears that the manufactured immobilized enzyme represents an appropriate choice for industrial use under harsh conditions, especially in the fisheries waste recovery industry.