The artificial engineering of an enzyme's structural conformation to enhance its activity is highly desired and challenging. Anisotropic reticular chemistry, best illustrated in the case of multivariate metal−organic frameworks (MTV-MOFs), provides a platform to modify a MOF's pore and inner-surface with functionality variations on frameworks to optimize the interior environment and to enhance the specifically targeted property. In this study, we altered the functionality and ratio of linkers in zeolitic imidazolate frameworks (ZIFs), a subclass of MOFs, with the MTV approach to demonstrate a strategy that allows us to optimize the activity of the encapsulated enzyme by continuously tuning the framework−enzyme interaction through the hydrophilicity change in the pores' microenvironment. To systematically study this interaction, we developed the component-adjustment-ternary plot (CAT) method to approach the optimal activity of the encapsulated enzyme BCL and revealed a nonlinear correlation, first incremental and then decremental, between the BCL activity and the hydrophilic linker' ratios in MTV-ZIF-8. These findings indicated there is a spatial arrangement of functional groups along the three-dimensional space across the ZIF-8 crystal with a unique sequence that could change the enzyme structure between closed-lid and open-lid conformations. These conformation changes were confirmed by FTIR spectra and fluorescence studies. The optimized BCL@ZIF-8 is not only thermally and chemically more stable than free BCL in solution, but also doubles the catalytic reactivity in the kinetic resolution reaction with 99% ee of the products.

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A Translation Invariance Denoising Algorithm with Wavelet Threshold and its Application on Signal Processing of Laser Interferometer Hydrophone is investigated. The obtained signal of Laser interferometer hydrophone exist a large number of singularity points, and the denoising algorithm of Donoho's wavelet threshold may produce the Pseudo Gibbs phenomenon on the singularity points. To eliminate the phenomenon, a denoising algorithm of wavelet threshold based on translation invariance is presented. The algorithm performs the cycle translation on the analyzed signal, and a soft threshold method is designed to shrink the wavelet coefficients of the signal and then we reconstruct the signal using the wavelet coefficients. The method can eliminate the oscillation of singularity points of the signal. Simulation experiments with the obtained data by the hydrophone show the algorithm is effectiveness.