Catalytically active inclusion bodies (CatIBs) induced by terminally attached self-assembling coiled-coil domains: To enhance the stability of (R)-hydroxynitrile lyase

The catalytically-active inclusion bodies (CatIBs) represent a promising strategy for immobilizing enzyme without additional carriers and chemicals, which has aroused great attention in academic and industrial communities. In this work, we discovered two natural parallel right-handed coiled-coil tetramer peptides from PDB database by a structural mining strategy. The two self-assembling peptides, NSPdoT from rotavirus and HVdoT from human Vasodilator-stimulated phosphoprotein, efficiently induced the CatIBs formation of a ( R )-Hydroxynitrile lyase from Arabidopsis thaliana ( At HNL) in Escherichia coli cells. This is convenient to simultaneously purify and immobilize the target proteins as biocatalysts. As expected, HVdoT- At HNL and NSPdoT- At HNL possessed drastically increased tolerance toward lower pH values, which will be very critical to synthesize cyanohydrins under acidic condition for suppressing the non-enzymatic side reaction. In addition. At HNL-CatIBs are produced at high yield in host cells as bioactive microparticles, which exhibited high thermal and pH stabilities. Therefore, the CatIBs method represent a promising application for the immobilization of enzymes in the biocatalysis field.