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Alginate oligosaccharides (AOS) show versatile bioactivities. Although various alginate lyases have been characterized, enzymes with special characteristics are still rare. In this study, a polysaccharide lyase family 7 (PL7) alginate lyase-encoding gene, aly08, was cloned from the marine bacterium Vibrio sp. SY01 and expressed in Escherichia coli. The purified alginate lyase Aly08, with a molecular weight of 35 kDa, showed a specific activity of 841 U/mg at its optimal pH (pH 8.35) and temperature (45 °C). Aly08 showed good pH-stability, as it remained more than 80% of its initial activity in a wide pH range (4.0–10.0). Aly08 was also a thermo-tolerant enzyme that recovered 70.8% of its initial activity following heat shock treatment for 5 min. This study also demonstrated that Aly08 is a polyG-preferred enzyme. Furthermore, Aly08 degraded alginates into disaccharides and trisaccharides in an endo-manner. Its thermo-tolerance and pH-stable properties make Aly08 a good candidate for further applications.

In spite of short-day (SD) nature, rice (Oryza sativa) shares a conserved photoperiodic network for flowering control with long-day plants like Arabidopsis thaliana. Flowering or heading is an important agronomic trait in rice. NAC transcription factors (TFs) are well-conserved and one of the largest families of plant TFs. However, their function in flowering or heading time is not well-known yet. A preferential expression of a membrane-bound NAC-like TF OsNTL5 in developing leaves and panicles of rice indicated to us its putative role in flowering. To examine its function, three independent constructs was generated, one with a deletion in the C terminus membrane-spanning domain (OsNTL5∆C), OsNTL5∆C fused with the SRDX transcriptional repressor motif and OsNTL5∆C used with the VP16 activation domain under the Ubiquitin promoter to produce the overexpressing lines OsNTL5∆C, OsNTL5∆C-SRDX, and OsNTL5∆C-VP, respectively in rice. The OsNTL5∆C-VP line showed an early-flowering phenotype. In contrast to this, the plants with OsNTL5∆C and OsNTL5∆C-SRDX showed a very strong late-flowering phenotype, suggesting that OsNTL5 suppresses flowering as a transcriptional repressor. The protein subcellular localization assay suggested that N-terminal part of the OsNTL5 is localized to the nucleus after the protein is cleaved from its membrane-spanning domain at the C-terminal end and functions as a TF. Expression of flowering genes responsible for day length signals such as Early Heading Date 1 (Ehd1), Heading Date 3a (Hd3a), and Rice Flowering Locus T1 (RFT1) was significantly changed in the overexpression lines of OsNTL5∆C-VP, OsNTL5∆C, and OsNTL5∆C-SRDX as analyzed by Quantitative Real-time PCR. ChIP-qPCR and rice protoplasts assays indicate that OsNTL5 directly binds to the promoter of Ehd1 and negatively regulates the expression of Ehd1, which shows antagonistic photoperiodic expression patterns of OsNTL5 in a 24-h SD cycle. Hence in conclusion, the NAC-like TF OsNTL5 functions as a transcriptional repressor to suppress flowering in rice as an upstream factor of Ehd1.

An earth–abundant photocatalytic system composed of an organic TADF photosensitizer and a simple terpyridine–Fe(III) complex was developed for CO2 reduction. In the presence of water, significant enhancement of CO generation...

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Mixed-metal oxides are one of the most frequently used catalysts in chemical industry, because the superior catalytic reactivity can be achieved by taking advantage of the synergetic effects of their parent oxides. However, the interfacial electronic interactions between metal oxides remain unclear, because of their structural complexity. This paper describes the modulation of catalytic performance of mixed RuO 2 /TiO 2 catalysts via adjusting the loading amount of RuO 2 . We show that, at very low loadings, the majority of RuO 2 catalysts can be anchored at the defective sites of TiO 2 substrates. Spectroscopic studies, combined with density functional calculations, indicate that electrons transfer from defective sites of substrates to RuO 2 , causing an increase in the apparent reaction barrier of CO oxidation. As the loading of Ru increases, RuO 2 starts to appear on the terrace of TiO 2 , and the apparent reaction barrier of CO oxidation decreases. At the medium loading of ∼0.75 wt %, the lowest apparent reaction barrier is achieved. The phenomenon can be attributed to the electron transfer from RuO 2 to the terrace of TiO 2 . By further increasing the loading of Ru, the apparent reaction barrier rises again. When the loading of Ru is more than 2 wt %, the apparent reaction barrier is found to be very comparable to that over RuO 2 catalysts supported on an inert substrate, indicating that the electronic effect of TiO 2 is isolated underneath thick RuO 2 overlayers. The demonstrated loading−electron transfer−reaction barrier relationship at RuO 2 /TiO 2 catalysts provides an insight into the interfacial interaction between mixed oxides and can be readily extended to many other catalytic systems.

The heat generated by a lithium-ion battery (LIB) under fast charging conditions can influence the charging efficiency, lifetime, and security of the battery. Considering the Joule heat generation of the tabs during the fast charging process, the electrochemical–thermal coupling model of a ternary LIB is built. The voltage and temperature of the battery are calculated during the constant current charging processes of 1 C, 3 C, and 6 C. By comparing the calculation results with the experiment results, the effectiveness of the model is verified. The electrochemical performance and thermal performance of the battery under fast charging conditions are obtained and analyzed through the model. The effects of the structure parameters such as the positive electrode thickness, N/P ratio, separator thickness, tab size, and arrangement on the average volume heat generation rate and temperature rise of the battery are investigated at charging rates of 3 C and 6 C. The conclusions obtained can provide references for the battery structure design and battery thermal management system design oriented to fast charging applications.