Penaeus vannamei protease stabilizing process of ZnS nanoparticles

The protease enzyme purified from the Penaeus vannamei shrimp has unique properties, so improving the stability of this enzyme can improve their practical applications. In this study, ZnS nanoparticles, which have special properties for enzyme immobilization, were synthesized using a chemical precipitation method, and Penaeus vannamei protease was successfully immobilized on them. The size, structure, and morphology of the ZnS nano particles, and the immobilization of the protease were studied, using Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FT-IR) spectroscopy, UV-Vis spectroscopy and Dynamic Light Scattering (DLS) analysis. We show that the immobilized enzyme has improved functionality at high temperatures, extreme pH conditions (pH 3 and 12), and during storage. Immobilization increased the optimum temperature range of the enzyme, but did not change the pH optimum, which remained at pH 7. Immobilization of P. vannamet protease enzyme increased the K-m and decreased K-cat/K-m. These results indicate that P. vannamei protease immobilized on ZnS nanoparticles, has improved properties due to its high stability and unique properties, can be used for biotechnology applications. (C) 2018 Elsevier B.V. All rights reserved