amir arasateh

Amyloids are created from various proteins in denaturant conditions. Highly active surface, makes these materials suitable for enzyme immobilization. The aim of this research was to study the production of amyloid fibrils and investigate the possibility of using them as a matrix for enzyme immobilization. Response surface methodology (RSM) was used to generate the maximum amyloid content. The results of the Congored spectrometry and circular dichroism (CD) were analyzed by Design Expert 7 software (Trial version) and transmission electron microscopy was used to confirm the presence of amyloid fibrils. The immobilization was done by creating glutaraldehyde mediated crosslink of enzyme on the amyloid fibrils and kinetic factors including activity, specific activity, optimal temperature and pH and thermal stability were compared with the free enzyme. The highest amyloid content was obtained after 72.6 hours agitation of bovine serum albumin at 4.35 mg.ml-1 in mixed citrate–phosphate buffer pH=4.49 at 80 ºC and immobilized lipase was improved relative to free lipase in the case of activity, specific activity, Km and Vmax, optimal temperature and pH and thermal stability at 40 ºC. Amyloid fibrils as a rich material of chemical groups can be suitable for stabilization. This protein matrix can be a good inVivo candidate as a bio–compatible scaffold for enzyme immobilization. Amyloids with a diameter less than 100 nanometers, as new nano–materials, not only increase the stability of lipase but also enhance other kinetic properties as a new nano–matrix.