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Plastic pollution and antibiotic resistance are two emerging environmental and human health crises today. Although it was revealed that microplastics can serve as vectors for the dissemination of antibiotic resistance, it is still unclear how the nanoplastics influence the horizontal transfer of antibiotic resistance genes (ARGs). Herein, we firstly compared the effect of polystyrene (PS) micro/nanoplastics on the transformation of plasmid‐borne ARG, using a transformation model consisting of plasmid pUC19 (ampR) and Escherichia coli DH5α (recipient). Due to its size effect, PS nanoplastics (10–500 mg/L) significantly enhanced the transformation efficiency (2.8–5.4 folds) and frequency (3.2–8.4 folds) of exogenous ampR into E. coli, while PS microplastics exerted no influence. The detailed mechanisms were found that nanoplastics induced reactive oxygen species (ROS) overproduction, activated SOS response, increased cell membrane permeability and changed the secretion systems, thereby facilitating the uptake of exogenous DNA by bacteria. Moreover, the co‐presences of nanoplastics with humic acid or Fe3+ relieved to some extent, but did not completely alleviate the promoting effect of nanoplastics on plasmid transformation. Our findings suggest that the risk of nanoplastics on promoting the dissemination of antibiotic resistance should not be neglected, and further studies are needed to investigate such risk in complex environments. [ABSTRACT FROM AUTHOR]

High salinity is one of the major limiting factors that reduces crop productivity and quality. Herein, we report that small SALT TOLERANCE ENHANCER1 (STE1) protein without any known conserved domains is required for tomato salt tolerance. Overexpression (OE) of SlSTE1 enhanced the tolerance to multiple chloride salts (NaCl, KCl, and LiCl) and oxidative stress, along with elevated antioxidant enzyme activities, increased abscisic acid (ABA) and chlorophyll contents, and reduced malondialdehyde (MDA) and reactive oxygen species (ROS) accumulations compared to that of wild‐type (WT) plants. Moreover, decreased K+ efflux and increased H+ efflux were detected in the OE plants, which induced a higher K+/Na+ ratio. In contrast, SlSTE1‐RNAi plants displayed decreased tolerance to salt stress. RNA‐seq data revealed 1 330 differentially expressed genes in the OE plants versus WT plants under salt stress, and the transcription of numerous and diverse genes encoding transcription factors, stress‐related proteins, secondary metabolisms, kinases, and hormone synthesis/signaling‐related proteins (notably ABA and 1‐aminocyclopropane‐1‐carboxylate) was greatly elevated. Furthermore, SlSTE1‐OE plants showed increased sensitivity to ABA, and the results suggest that SlSTE1 promotes ABA‐dependent salt stress‐responsive pathways by interacting with SlPYLs and SlSnRK2s. Collectively, our findings reveal that the small SlSTE1 protein confers salt tolerance via ABA signaling and ROS scavenging and improves ion homeostasis in tomato. [ABSTRACT FROM AUTHOR]

The AP2/ERF transcription factors (TFs) regulate various processes of plant growth, development, and response to environmental stimuli. Although they have been extensively documented in many plants, little is known about stress responsive APETALA2/ethylene response factor (AP2/ERF) genes in sweetpotato (Ipomoea batatas L.). In this study, 20 putative AP2/ERF genes, named IbERF1, IbERF2, and IbERF5–IbERF23 were identified based on the salt‐treated RNA‐seq data from two sweetpotato cultivars with different salt tolerance. Phylogenetic analysis and sequence characterization identified that all the screened IbERF proteins contained a conserved AP2 domain, which belonged to dehydration‐responsive element binding proteins (DREB; 7 members) or ERF (13 members) subfamily. The systematic expression analysis of 12 mainly salt‐induced IbERFs by quantitative real‐time polymerase chain reaction (qRT‐PCR) revealed that most IbERFs were remarkably increased by multiple abiotic stresses, such as NaCl, dehydration, and cold stress. Furthermore, varying degrees of upregulation were also detected in the expression of most IbERFs when treated with hormone abscisic acid, jasmonic acid, and salicylic acid. The expression profiles of IbERFs corroborate their involvement in diverse biological processes. In addition, the IbERF5, which was exclusively upregulated by the treatments, was identified as a nuclear protein without transcriptional activation activity. Collectively, the data of stress responsive IbERFs will provide valuable knowledge for further functional studies of IbERFs in sweetpotato stress tolerance. [ABSTRACT FROM AUTHOR]

An eco-efficient, green, and multi-gram procedure is presented for one-pot multicomponent synthesis of N-substituted 1,2,3-triazoles by using waste fishbone powders supported CuBr (FBPs-CuBr) as catalyst. FBPs-CuBr is found to be an efficient heterogeneous catalyst and a series of 1,2,3-triazoles are obtained in moderate to excellent yields in water under MW irradiation (70-98%). It can be separated conveniently by a simple filtration and reused at least seven consecutive runs with a slight drop in the product yields. Furthermore, the desired product still could be obtained in 80% yield when the scale of the reaction was increased to 40.0 mmol. [ABSTRACT FROM AUTHOR]