Entrapment of parathion hydrolase from Pseudomonas spp. in sol-gel glass |
| |
Authors: | C Dosoretz R Armon J Starosvetzky N Rothschild |
| |
Institution: | (1) MIGAL-Galilee Technological Center, 10200 Kyriat Shmona, Israel;(2) Environmental & Water Resources Engineering, Technion, 32000 Haifa, Israel;(3) Environmental & Water Resources Engineering, Technion, 32000 Haifa, Israel;(4) MIGAL-Galilee Technological Center, 10200 Kyriat Shmona, Israel |
| |
Abstract: | The present work reports on the entrapment of parathion hydrolase from Pseudomonas spp. into the sol-gel glass matrix. Enzyme entrapment was studied in the range of 0.01–0.25 U, and compared with the activity of the free, non-immobilized enzyme. The reaction catalyzed by the entrapped enzyme was almost two orders of magnitude slower than with the free enzyme. Addition of surfactants slightly increased the parathion hydrolysis rate, and the addition of ethanol almost doubled it. However, this increase of reaction rate cannot by itself explain the decrease of activity, suggesting that irreversible damage to the enzyme during gelation, rather than diffusion limitation throughout the gel-glass structure, is the main cause for the decrease of activity. Regardless of damage to the enzyme during gelation, the remaining entrapped active fraction displayed stability even after eleven days, during successive cycles of the same entrapped enzyme batch, each for 24 h. The sol-gel entrapped enzyme retained relatively good activity for several months when stored as a dry powder, and over a year when kept in buffer solution, at ambient conditions. The results obtained may give a rise to the use of entrapped parathion hydrolase for simple on-field bio-detection of organophosphates. |
| |
Keywords: | parathion hydrolase sol-gel glass enzyme entrapment organophosphates |
本文献已被 SpringerLink 等数据库收录! |
|