A solid-state NMR study of the immobilization of alpha-chymotrypsin on mesoporous silica

Faure, N. E. and Halling, P. J. and Wimperis, S. (2014) A solid-state NMR study of the immobilization of alpha-chymotrypsin on mesoporous silica. Journal of Physical Chemistry C, 118 (2). pp. 1042-1048. (https://doi.org/10.1021/jp4098414)

Full text not available in this repository.Request a copy

Abstract

Solid-state NMR spectroscopy was used to characterize a model biocatalyst system consisting of the enzyme α-chymotrypsin covalently immobilized on epoxide-silica ((glycidoxypropyl)trimethoxysilane, GOPS, grafted onto the surface of a silica gel). One- and two-dimensional 1H, 13C, and 29Si 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 13C MAS NMR spectra recorded at B0 = 20 T. A number of further changes were observed in the 13C and 29Si 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.