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BACKGROUND The metal–organic framework (MOF) ZIF‐8 has the advantages of a large specific surface area and high stability. A new strategy for the assembly of amino acid dehydrogenase with peptide linker and for improving enzyme immobilization is proposed. RESULTS: Peptide linker enhanced enzyme activity after immobilization by 138.7%, and maintained 81.2% of its initial activity after seven recycles. The stability of PheDH_1D02/ZIF‐8 was greatly enhanced at 70–80 °C and pH 10–11. The catalytic efficiency of PheDH_1D02/ZIF‐8 was also enhanced compared with PheDH_1C1D/ZIF‐8 and two free enzymes. CONCLUSIONS: Metal ions coordinated with the peptide linker and reoriented immobilization of enzyme onto the MOF with high enzyme loading capacity were achieved. The mesoporous structure of PheDH_1D02/ZIF‐8 facilitates substrate diffusion. Combining the assembly of peptide linker and MOF immobilization is a simple, economical and efficient method for improving dehydrogenase stability. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

BACKGROUND Dehydrogenases dependent on NAD(P)H are widely applied for biosynthesis of chiral chemicals. However, they are unstable and easy denaturated compared with hydrolases. A new strategy for dehydrogenases immobilization with the advantages of easy operation and high activity recovery should be developed. Biocompatible hybrid materials (GO‐PEI‐M) have been obtained by metal ions coordinated polyethylenimine (PEI) functionalized graphene oxide (GO). RESULTS: The immobilized enzyme recovery rates of GO‐PEI‐Mg (magnesium ion coordinated GO‐PEI) and GO‐PEI‐Mn (manganese ion coordinated GO‐PEI). In addition, the stability of GO‐PEI‐Mn‐PheDH (Phenylalanine Dehydrogenase) and GO‐PEI‐Mg‐PheDH was greatly improved, and it maintained 65% and 79% activity, respectively, after seven times reuse. In addition, the stability of GO‐PEI‐Mn‐PheDH (Phenylalanine Dehydrogenase) and GO‐PEI‐Mg‐PheDH was greatly improved. After seven times reuse, GO‐PEI‐Mn‐PheDH and GO‐PEI‐Mn‐PheDH and maintained 65% and 79% activity, respectively. An assembly mechanism was proposed from the perspectives of multi‐level interactions, including hydrogen bonding, electrostatic forces, and coordinated bonds. CONCLUSION: GO‐PEI‐Metal ion hybrid materials offer a promising carrier for enzyme immobilization with the advantages of biocompatibility and relatively strong interaction. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]