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We investigated the pressure-dependent exciton absorption and photoluminescence (PL) properties of colloidal InAs/ZnSe core/shell quantum dots (QDs) emitting near-infrared (NIR) photons, an environmentally friendly alternative to heavy-metal-containing NIR QDs. A detailed analysis of exciton absorption and emission spectra was conducted in the pressure range of 0–10 GPa, focusing on the energy shifts, PL intensity, and lineshape changes with pressure. The pressure coefficients for exciton absorption and PL peaks were ∼70% of the bulk InAs value, with enhanced bandgap nonlinearity tentatively attributed to the higher bulk modulus of QDs compared to bulk material. The pressure-induced shifts in exciton absorption and PL peaks were reversible upon compression and decompression, with no indication of the semiconductor-to-metallic phase transition observed in bulk InAs around 7 GPa. However, PL intensity exhibited partial irreversibility, suggesting defect formation at the core/shell interface under pressure. From the findings of this study, along with previous high-pressure studies on molecular beam epitaxy-grown InAs QDs on GaAs, we infer the importance of the shell in determining the pressure response of exciton absorption and PL in core/shell QD structures with non-negligible interfacial strain and wave function spill into the shell. 

Abstract Acyltransferases (AT) are enzymes that catalyze the transfer of acyl group to a receptor molecule. This review focuses on ATs that act on thioester‐containing substrates. Although many ATs can recognize a wide variety of substrates, sequence similarity analysis allowed us to classify the ATs into fifteen distinct families. Each AT family is originated from enzymes experimentally characterized to have AT activity, classified according to sequence similarity, and confirmed with tertiary structure similarity for families that have crystallized structures available. All the sequences and structures of the AT families described here are present in the thioester‐active enzyme (ThYme) database. The AT sequences and structures classified into families and available in the ThYme database could contribute to enlightening the understanding acyl transfer to thioester‐containing substrates, most commonly coenzyme A, which occur in multiple metabolic pathways, mostly with fatty acids.