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Magnetic and Thermal-sensitive PolyN-isopropylacrylamide-based Microgels for Magnetically Triggered Controlled Release
Published on: July 4, 2017
Refolding of thermally denatured cholesterol oxidases by magnetic nanoparticles
Shubhrima Ghosh1, Razi Ahmad1, S K Khare1
1Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India.
Abstract:
Proteins are prone to unfolding and subsequent denaturation by changes in temperature, pH and other harsh conditions. Nanoparticles act as artificial 'chaperones' due to favourable orientation of the proteins on their scaffold which prevents aggregation and reconfigures denatured proteins into their native functional state. In the present study, thermal denaturation of Cholesterol oxidases from Pseudomonas aeruginosa PseA, Rhodococcus erythropolis MTCC 3951 and Streptomyces sp. were studied at temperatures 50-70 °C. Further, these thermally denatured proteins were refolded using functionalized Magnetic Iron (II, III) oxide nanoparticles which was confirmed using DLS, Zeta Potential Measurements, fluorescence and CD spectroscopy. The refolded proteins were found to regain their secondary structure and activity to a great extent.
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