RT Journal Article
T1 Positively charged mini-protein Zbasic2 as a highly efficient silica binding module: opportunities for enzyme immobilization on unmodified silica supports
A1 Bolívar Bolívar, Juan Manuel
A1 Nidetzky, Bernd
AB Silica is a highly attractive support material for protein immobilization in a wide range of biotechnological and biomedical-analytical applications. Without suitable derivatization, however, the silica surface is not generally usable for attachment of proteins. We show here that Zbasic2 (a three α-helix bundle mini-protein of 7 kDa size that exposes clustered positive charges from multiple arginine residues on one side) functions as highly efficient silica binding module (SBM), allowing chimeras of target protein with SBM to become very tightly attached to underivatized glass at physiological pH conditions. We used two enzymes, d-amino acid oxidase and sucrose phosphorylase, to demonstrate direct immobilization of Zbasic2 protein from complex biological samples with extremely high selectivity. Immobilized enzymes displayed full biological activity, suggesting that their binding to the glass surface had occurred in a preferred orientation via the SBM. We also show that charge complementarity was the main principle of affinity between SBM and glass surface, and Zbasic2 proteins were bound in a very strong, yet fully reversible manner, presumably through multipoint noncovalent interactions. Zbasic2 proteins were immobilized on porous glass in a loading of 30 mg protein/g support or higher, showing that attachment via the SBM combines excellent binding selectivity with a technically useful binding capacity. Therefore, Zbasic2 and silica constitute a fully orthogonal pair of binding module and insoluble support for oriented protein immobilization, and this opens up new opportunities for the application of silica-based materials in the development of supported heterogeneous biocatalysts.
PB American Chemical Society
SN 0743-7463
YR 2012
FD 2012
LK https://hdl.handle.net/20.500.14352/92775
UL https://hdl.handle.net/20.500.14352/92775
LA eng
NO Bolivar, J. M., & Nidetzky, B. (2012). Positively charged mini-protein Z basic2 as a highly efficient silica binding module: Opportunities for enzyme immobilization on unmodified silica supports. Langmuir, 28(26), 10040-10049. https://doi.org/10.1021/LA3012348
NO Ministerio de Educación (España)
NO Austrian Centre of Industrial Biotechnology
DS Docta Complutense
RD 21 abr 2025