A Solid-State NMR Study of the Immobilization of alpha-Chymotrypsin on Mesoporous Silica

作者：Faure Nicole E; Halling Peter J^*; Wimperis Stephen

来源：Journal of Physical Chemistry C, 2014, 118(2): 1042-1048.

DOI：10.1021/jp4098414

Solid-state NMR spectroscopy was used to characterize a model biocatalyst system consisting of the enzyme alpha-chymotrypsin covalently immobilized on epoxide-silica ((glycidoxypropyl)trimethoxysilane, GOPS, grafted onto the surface of a silica gel). One- and two-dimensional H-1, C-13, and Si-29 magic angle spinning (MAS) NMR techniques were employed. The support system (epoxide-silica) was characterized first and it was possible to assign silicon and carbon species in both the silica and the GOPS linker. After attachment of the protein, carbonyl carbons (175 ppm) in the immobilized enzyme were visible in C-13 MAS NMR spectra recorded at B-o = 20 T. A number of further changes were observed in the C-13 and Si-29 MAS NMR spectra during the immobilization process, arising from a cross-linking of the surface silica species and an opening of the epoxide functional group by nucleophilic attack. This study shows the potential of multinuclear solid-state NMR for obtaining a better understanding of solid biocatalyst systems at the molecular level.

• 出版日期2014-1-16