DNA Origami Nanoplate‐Based Emulsion with Nanopore Function

Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial‐cell engineering. Although particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilic DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and to stabilise the oil–water interface. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil–water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for the programmable design of microcapsules to engineer artificial cells and molecular robots.     

Alkyl Chain Length- and Polymorph-Dependent Photomechanochromic Fluorescence of Anthracene Photodimerization in Molecular Crystals: Role of the Lattice Stiffness

Anthracene–pentiptycene hybrid systems 1-Cn , where n refers to the number of carbon atoms in the linear alkyl chain, crystallize in three different polymorphs, denoted Y (yellow), G (green), and B (blue) forms in terms of the fluorescence color. While all Y-form crystals show the same yellow-to-blue fluorescence color response to the photomechanical stress generated by the anthracene [4+4] photodimerization reaction, the four G forms exhibit distinct photomechanofluorochromism (PMFC): from green to blue for G-1-C4 , to orange for G-1-C7 , to red for G-1-C8 , and to red then blue for G-1-C9 , and the B forms show no photochromic activity. The intriguing RGB three-color PMFC and abnormal topochemical reactivity of G-1-C9 are attributed to inherent softness of the crystal lattice.     

Gold‐Palladium Nanocluster Catalysts for Homocoupling: Electronic Structure and Interface Dynamics

The gold‐palladium (Au?Pd) bimetallic nanocluster (NC) catalyst in colloidal phase performs the homocoupling reaction of various aryl chlorides (Ar?Cl) under ambient conditions. We have systematically investigated various aspects of the Au?Pd NC catalysts with respect to this homocoupling reaction by using density functional theory (DFT) calculations, genetic algorithm (GA) approaches, and molecular dynamics (MD) simulations. Our findings include the geometric and electronic structures of the Au?Pd NC, the reactive Pd sites on the NC surface, the electron‐donating effects of surrounding polymer matrix, the reaction mechanism of homocoupling reaction and rate‐determining step, the inverse halogen dependence of the reaction, and the solvation dynamics at interface region between NC and polymer matrix in aqueous solution.     

Total synthesis and determination of the absolute configuration of paralemnolin C and biological studies of eremophilane derivatives

The first asymmetric total synthesis of paralemnolin C was achieved. The absolute configuration at C11 of this natural product was determined from the X-ray crystallographic analysis of the epoxide derivative. In addition, biological studies of eremophilane derivatives including paralemnolin C and sagittacin E were carried out.     

Enzymatic Cell-Surface Decoration with Proteins using Amphiphilic Lipid-Fused Peptide Substrates

Lipid modification of proteins plays a significant role in the activation of cellular signals such as proliferation. Thus, the demand for lipidated proteins is rising. However, getting a high yield and purity of lipidated proteins has been challenging. We developed a strategy for modifying proteins with a wide variety of synthetic lipids using microbial transglutaminase (MTG), which catalyzes the cross-linking reaction between a specific glutamine (Q) in a protein and lysine (K) in the lipid-fused peptide. The synthesized lipid-G₃S-MRHKGS lipid (lipid: fatty acids, tocopherol, lithocholic acid, cholesterol) was successfully conjugated to a protein fused with LLQG (Q-tagged protein) by an MTG reaction, yielding >90 % conversion of the Q-tagged protein in a lipidated form. The purified lipid–protein conjugates were used for labeling the cell membrane in vitro, resulting in best-anchoring ability of cholesterol modification. Furthermore, in situ cell-surface decoration with the protein was established in a simple manner: subjection of cells to a mixture of cholesterol-fused peptides, Q-tagged proteins and MTG.     

Revisiting the Bromination of CH Bonds with Molecular Bromine by Using a Photo‐Microflow System

The photobromination of C?H bonds by using molecular bromine was reinvestigated under microfluidic conditions. The continuous‐flow method suppressed the production of dibrominated compounds and effectively produced the desired monobrominated products with high selectivity. Rapid bromination of benzylic substrates containing a photoaffinity azide group was achieved without any decomposition.