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Much more attention has been paid to the contamination of Alternaria toxins because of food contamination and the threat to human health. In this study, an ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for the simultaneous detection of the prototypical alternariol, alternariol monomethylether, and the metabolites 4‐oxhydryl alternariol, and alternariol monomethylether 3‐sulfate ammonium salt of Alternaria toxins. The positive samples were used as matrix samples to optimize the different experimental conditions. 0.01% formic acid solution and acetonitrile were used as the mobile phase, and analytes were scanned in negative electron spray ionization under multiple reaction monitoring, and quantitative determination by isotope internal standard method. Application of this method to samples of human plasma and urine showed the detection of the above analytes. The results showed that the recoveries were from 80.40% to 116.4%, intra‐day accuracy was between 0.6% and 8.0%, and inter‐day accuracy was between 1.1% and 12.1%. The limit of detection of the four analytes ranged from 0.02 to 0.6 µg/L in urine, and 0.02 to 0.5 µg/L in plasma, respectively. Thus, the developed method was rapid and accurate for the simultaneous detection of analytes and provided a theoretical basis for the risk assessment of Alternaria toxins for human exposure. [ABSTRACT FROM AUTHOR]

Natural proteins display organized hierarchical structures and tailored functionalities that cannot be achieved by synthetic approaches, highlighting the increased interest in developing protein‐based materials. Protein self‐assembly allows fabricating sophisticated supramolecular structures from relatively simple building blocks, a strategy naturally employed by amyloid proteins and intrinsically disordered proteins. However, the design of self‐assembled bioinspired materials with multi functionalities is still challenging. Inspired by the natural self‐assembly proteins (such as mussel foot proteins and amyloid proteins), a temperature‐inducible engineering programable hydrogel‐like amyloid nanostructure is developed by using a genetically modular fusion approach. The resulting hydrogel‐like assemblies display outstanding adhesive capacity, high stability, and broad substrate universality. The employed SpyCatcher/SpyTag system allows modifying the hydrogel‐like assemblies with any functional proteins of interest. Owing to their strong adhesive capacity and functional flexibility, such amyloid fibril‐based hydrogel shows advantages in the immobilization of diverse enzymes for highly efficient biocatalysis, fabrication of multi‐layered functional coatings, and construction of functionalized 3D scaffold for cell culture. Overall, a modular and straightforward approach is established to obtain a genetically programable nanostructure platform. The novel hydrogel‐like assemblies described here may be potentially applied to but not limited to synthetic biology, surface/interface engineering, and tissue engineering. [ABSTRACT FROM AUTHOR]

Dark carbon fixation (DCF), through which chemoautotrophs convert inorganic carbon to organic carbon, is recognized as a vital process of global carbon biogeochemical cycle. However, little is known about the response of DCF processes in estuarine and coastal waters to global warming. Using radiocarbon labelling method, the effects of temperature on the activity of chemoautotrophs were investigated in benthic water of the Yangtze estuarine and coastal areas. A dome‐shaped thermal response pattern was observed for DCF rates (i.e., reduced rates at lower or higher temperatures), with the optimum temperature (Topt) varying from about 21.9 to 32.0°C. Offshore sites showed lower Topt values and were more vulnerable to global warming compared with nearshore sites. Based on temperature seasonality of the study area, it was estimated that warming would accelerate DCF rate in winter and spring but inhibit DCF activity in summer and fall. However, at an annual scale, warming showed an overall promoting effect on DCF rates. Metagenomic analysis revealed that the dominant chemoautotrophic carbon fixation pathways in the nearshore area were Calvin‐Benson‐Bassham (CBB) cycle, while the offshore sites were co‐dominated by CBB and 3‐hydroxypropionate/4‐hydroxybutyrate cycles, which may explain the differential temperature response of DCF along the estuarine and coastal gradients. Our findings highlight the importance of incorporating DCF thermal response into biogeochemical models to accurately estimate the carbon sink potential of estuarine and coastal ecosystems in the context of global warming. [ABSTRACT FROM AUTHOR]