Abstract
The effect on protein conformation and thermal stability was studied for β-Galactosidase (β-Gal) encapsulated in the nanopores of a silicate matrix (Eβ-Gal). Circular dichroism spectra showed that, compared with the enzyme in buffer (Sβ-Gal), Eβ-Gal exhibited a higher content of α-helix structure. Heating Eβ-Gal up to 75 °C caused a decrease in the content of β-sheet structure and additional augments on Eβ-Gal components attributed to helical content, instead of the generalized loss of the ellipticity signal observed with Sβ-Gal. Steady state fluorescence spectroscopy analysis evidenced an Eβ-Gal structure less compact and more accessible to solvent and also less stable against temperature increase. While for Sβ-Gal the denaturation midpoint (Tm) was 59 °C, for Eβ-Galit was 48 °C. The enzymatic activity assays at increasing temperatures showed that in both conditions, the enzyme lost most of its hydrolytic activity against ONPG at temperatures above 65 °C and Eβ-Gal did it even at lower T values. Concluding, confinement in silica nanopores induced conformational changes on the tertiary/cuaternary structure of Eβ-Gal leading to the loss of thermal stability and enzymatic activity.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Biochemical and Biophysical Research Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
