PETase displays great potential in PET depolymerization. Directed evolution has been limited to engineer PETase due to the lack of high-throughput screening assay. In this study, a novel fluorescence-based high-throughput screening assay employing a newly designed substrate, bis (2-hydroxyethyl) 2-hydroxyterephthalate (termed BHET-OH), was developed for PET hydrolases. The best variant DepoPETase produced 1407-fold more products towards amorphous PET film at 50 °C and showed a 23.3 °C higher T m value than the PETase WT. DepoPETase enabled complete depolymerization of seven untreated PET wastes and 19.1 g PET waste (0.4 % W enzyme /W PET ) in liter-scale reactor, suggesting that it is a potential candidate for industrial PET depolymerization processes. The molecular dynamic simulations revealed that the distal substitutions stabilized the loops around the active sites and transmitted the stabilization effect to the active sites through enhancing inter-loop interactions network.

Asymmetric cell division (ACD) produces morphologically and behaviorally distinct cells and is the primary way to generate cell diversity. In the model bacterium Caulobacter crescentus, the polarization of distinct scaffold-signaling hubs at the swarmer and staked cell poles constitutes the basis of ACD. However, mechanisms involved in the formation of these hubs remain elusive. Here, we show that a swarmer-cell-pole scaffold, PodJ, forms biomolecular condensates both in vitro and in living cells via phase separation. The intrinsically disordered and coiled-coil 4-6 regions of PodJ mediate biomolecular condensate generation and its signaling protein recruitment. Moreover, a negative regulation of PodJ phase separation by the staked-cell-pole scaffold protein SpmX is revealed and SpmX disturbs PodJ subcellular accumulation and affects its recruitment ability. Together, by modulating the assembly and dynamics of scaffold-signaling hubs, phase separation may serves as a general biophysical mechanism that underlies the regulation of ACD in bacteria and other organisms.

Nanocomposites with hierarchical pore structure hold great potentials for applications in the field of microwave‐absorbing materials because of their lightweight and high‐efficiency absorption properties. Herein, M‐type barium ferrite (BaM) with ordered mesoporous structure (M‐BaM) is prepared via a sol–gel process enhanced by mixed anionic and cationic surfactants. The surface area of M‐BaM is enhanced almost ten times compared with BaM together with 40% reflection loss enhancing. Then M‐BaM compounded with nitrogen‐doped reduced graphene oxide (MBG) is synthesized via hydrothermal reaction in which the reduction and nitrogen doping of graphene oxide (GO) in situ occur simultaneously. Interestingly, the mesoporous structure is able to provide opportunity for reductant to enter the bulk M‐BaM reducing its Fe3+ to Fe2+ and further forms Fe3O4. It requires an optimal balance among the remained mesopores in MBG, formed Fe3O4, and CN in nitrogen‐doped graphene (N‐RGO) for optimizing impedance matching and greatly increasing multiple reflections/interfacial polarization. MBG‐2 (GO:M‐BaM = 1:10) achieves the minimum reflection loss of −62.6 dB with an effective bandwidth of 4.2 GHz at an ultra‐thin thickness of 1.4 mm. In addition, the marriage of mesoporous structure of M‐BaM and light mass of graphene reduces the density of MBG.

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