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Abscisic acid (ABA), a critical phytohormone that regulates plant development and stress response, is sensed by the ABA receptors PYR/PYL/RCAR (PYLs). The PYL genes have been widely studied in multiple plant species, while a systematic analysis of PYL genes in the genus Ipomoea remains unperformed. Here, a total of 13, 14, and 14 PYLs were identified in Ipomoea batatas, Ipomoea trifida, and Ipomoea triloba, respectively. Fragment duplication was speculated to play prominent roles in Ipomoea PYL gene expansions. These Ipomoea PYLs were classified into three subfamilies via phylogenetic analysis, which was supported by exon–intron structures and conserved motif analyses. Additionally, the interspecies collinearity analysis further depicted a potential evolutionary relationship between them. Moreover, qRT-PCR analysis showed that multiple IbPYLs are highly and differentially responsive to abiotic stress treatments, suggesting their potential roles in sweetpotato stress responses. Taken together, these data provide valuable insights into the PYLs in the genus Ipomoea, which may be useful for their further functional analysis of their defense against environmental changes. [ABSTRACT FROM AUTHOR]

Sulfamethoxazole (SMX) contamination in large quantities of wastewater can cause potential environmental problems. Due to difficulty in degrading SMX by natural processes, it is necessary to develop a novel technology to solve this problem. Advanced oxidation processes (AOPs) have been identified as methods with a high potential to treat recalcitrant organic pollutants. The nanoscale schwertmannite (nano-SWT) was prepared with an indoor-temperature synthesis method facilitated by polyvinylpyrrolidone (PVP). In this study, we performed a reaction of the nano-SWT materials with Fenton-like catalysts for SMX degradation in hydrogen peroxide (H2O2) media. The findings showed that the nano-SWT prepared by addition of 0.1 g·L−1 PVP (nano-SWT-n, n = 0.1) could degrade 92.5% of the SMX within 90 min at indoor temperature, which was due to the nano-SWT providing abundant reaction sites at the solid/solution interfaces. Additionally, SMX could be highly mineralized with 75% TOC removal and H2O2 was efficiently utilized during the nano-SWT/H2O2 process. In addition, after six cycles of Fenton-like degradation, the nano-SWT remained stable and reusable as a Fenton-like catalyst for SMX degradation. The nano-SWT performed well as a catalyst for SMX degradation. Additionally, this work provides a feasible environmental purification approach for the efficient degradation of SMX through the use of nanoscale schwertmannite as a catalyst in heterogeneous Fenton-like systems. [ABSTRACT FROM AUTHOR]

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]

Near-infrared (NIR) organic dyes have received increasing attention in recent years as diagnostic and therapeutic agents in the field of tumor research. In this study, IR-822, a near-infrared fluorescence (NIRF) heptamethine cyanine dye, was chosen as a fluorophore due to its high extinction coefficients, and native preferential tumor accumulation property. To enhance its specificity in tumor imaging, N1-(pyridin-4-ylmethyl)ethane-1,2-diamine (PY) was conjugated to IR-822 as a pH-sensing receptor, forming a fluorophore–spacer–receptor molecular probe (IR-PY) that can modulate the fluorescence emission intensity through a fast photoinduced electron-transfer process, which allowed the probe to “switch on” significantly in an acidic tumor microenvironment and which realized enhanced NIRF imaging in vivo. Having a strong NIR absorption at 600–850 nm, this small-molecule IR-PY showed not only high spatial resolution photoacoustic (PA) imaging in mice, but also effective tumor photothermal ablation in vivo. After photothermal therapy (PTT) with IR-PY under NIR 808 nm laser irradiation, the mice exhibited remarkable ablation with no tumor recurrence after treatment. Therefore, a single smart small-molecule probe IR-PY has been designed, synthesized and verified as an “all in one” multifunctional agent, including pH sensitivity, tumor targeting, “switch-on” near-infrared fluorescence imaging, high-spatial-resolution PA imaging and efficient near-infrared photothermal therapy, which is promising for clinical application in NIRF/PA dual-modal imaging-guided cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Sweet potato [ Ipomoea batatas (L.) Lam.] is a vegetable crop with significant economic value that is utilized both as a staple food and as an industrial raw material. Sweet potato possesses a variety of healthful beneficial secondary metabolites, which also contribute towards its adaptation to the environment and capacity to withstand stresses. Cinnamate 4-hydroxylase constitutes a primary enzyme in the phenylpropanoid pathway that is involved in the biosynthesis of numerous secondary metabolites. Elucidating the molecular and expressional characteristics of C4H is essential for understanding the functional genetic diversity of sweet potato germplasms. Based on the transcriptome analysis of five sweet potato genotypes with different anthocyanin contents, a cinnamate 4-hydroxylase ( C4H) gene, termed IbC4H, was isolated from a purple sweet potato cv. 'Xuzishu 3'. The cDNA sequence of IbC4H contained a 1518-bp ORF encoding a 505 amino acid protein with a molecular weight of 58.15 kDa. Genomic DNA analysis revealed that the IbC4H gene possessed three exons and two introns. The IbC4H protein shared 86.34-97.82% sequence identity with that reported for other plants. A significant positive correlation between the expression of IbC4H and phenolic acid content suggested that IbC4H might be integral to the regulation of phenolic biosynthesis in sweet potato. Furthermore, IbC4H was significantly upregulated in the young leaves and roots of cv. 'Xuzishu 3' and was strongly induced when subjected to drought stress. Drought stress tolerance in transgenic tobacco plants was significantly improved by the heterologous expression of the transgene IbC4H, which was simultaneously associated with the increased expression of stress-related genes, higher superoxide dismutase (SOD) activity, and proline (Pro) content, along with lower malondialdehyde (MDA) production. Collectively, these results highlight the important role of IbC4H in the phenylpropanoid pathway and support the protective function of polyphenols in the improved scavenging of reactive oxygen species of plants under stress. [ABSTRACT FROM AUTHOR]

Schwertmannite, jarosite or goethite are commonly used to remove metals and/or metalloids from contaminated water via adsorption processes, but it is still unclear whether they can be used as adsorbents to remove hydrophobic organic pollutants (HOCs), such as polycyclic aromatic hydrocarbons (PAHs), from groundwater or wastewater. Here, the feasibility of using these iron (oxyhydr) oxide minerals as adsorbents for phenanthrene (a model PAH) adsorption and regenerating the spent adsorbents via heterogeneous Fenton-like reaction was investigated. Results showed that they exhibited rapid adsorption rates and considerable adsorption capacities for phenanthrene. The maximum Langmuir capacities (Qmax) for phenanthrene adsorption at 28 °C were in an ascending order of goethite (567 μg·g-1) < schwertmannite (727 μg·g-1) < jarosite (2088 μg·g-1). The adsorption process was a spontaneous and exothermic process along with the decrease of randomness at the solid/liquid interfaces, which was influenced by temperature, adsorbent dosage, and the coexistence of inorganic anions. Both schwertmannite and jarosite were superior to goethite in light of their easy separation from the bulk solution after the adsorption processes. A multi-cycle experiment demonstrated that the regeneration efficiency of schwertmannite (97.9–99.7%) was much higher than that of jarosite (80.1–87.2%), and the mineral structure, morphology and functional groups of schwertmannite were not changed during the successive adsorption-regeneration processes. Therefore, among the investigated three iron (oxyhydr) oxide minerals, schwertmannite was an attractive and regenerable adsorbent for the removal of phenanthrene from water owing to its high adsorption capacity, good separation ability, and excellent reusability. Image 1 • Schwertmannite, jarosite and goethite can rapidly adsorb phenanthrene. • The adsorption process was a spontaneous and exothermic process. • Schwertmannite and jarosite had better separation ability than goethite. • The regeneration efficiency of schwertmannite was as high as 97.9–99.7%. [ABSTRACT FROM AUTHOR]

Betalains are applicable to many aspects of life, and their properties, characteristics, extraction and biosynthesis process have been thoroughly studied. Although betalains are functionally similar to anthocyanins and can substitute for them to provide pigments for plant color, it is rare to study the roles of betalains in plant responses to adverse environmental conditions. Owing to their antioxidant capability to remove excess reactive oxygen species (ROS) in plants and humans, betalains have attracted much attention due to their bioactivity. In addition, betalains can also act as osmotic substances to regulate osmotic pressure in plants and play important roles in plant responses to adverse environmental conditions. The study of the physiological evolution of betalains is almost complete but remains complicated because the evolutionary relationship between betalains and anthocyanins is still uncertain. In this review, to provide a reference for the in-depth study of betalains compared with anthocyanins, the biochemical properties, biosynthesis process and roles of betalains in response to environmental stress are reviewed, and the relationship between betalains and anthocyanins is discussed. [ABSTRACT FROM AUTHOR]

The catalytic activity of palladium (Pd) nanostructures highly relies on their size and morphology, especially enclosed with high-index facets, which provide more active sites so as to enhance their catalytic performance comparing with their low-index facet counterparts. Herein, Pd concave nanocubes enclosed with {730} facets by a one-pot scalable liquid method, with various high-index facets are synthesized via tuning reduction kinetics. Due to their high-index facets, the Pd concave nanocubes exhibit much higher electrocatalytic activity and stability for methanol oxidation than the Pd nanocubes enclosed by {100} facets and commercial Pd/C. Furthermore, we scale up synthesis of Pd concave nanocubes by expanding the volume of all species to fifty times with high-yield production. [ABSTRACT FROM AUTHOR]

Basic region/leucine zipper (bZIP) transcription factors function as critical regulators in numerous abiotic stress responses. Massive bZIPs have been systematically identified in plants, but not in sweetpotato. In this study, 87 sweetpotato IbbZIPs unevenly distributed onto 15 chromosomes were identified, and segmental duplications were shown to play dominant roles in the diversity of IbbZIPs. The collinearity between IbbZIPs and the related orthologs from nine plants depicted evolutionary insights into bZIP gene family. Additionally, IbbZIP proteins were clustered into 11 subfamilies while no members were found in the M subfamily, and the regularity of gene structures and conserved motifs was consistent with the subgroup classification. Evidence from transcriptome data and qRT-PCR analysis of 12 selected IbbZIPs revealed that they were significantly and varyingly induced under multiple abiotic stresses (salt, drought, heat and cold) and hormone treatments (ABA, ACC, JA and SA). Consistently, the promoters of IbbZIPs harbored multiple stress- and hormone-related cis-acting elements. Besides, IbbZIP17 and IbbZIP61 exhibited transactivation activity in yeasts, while IbbZIP-14/-69/-84 did not. These findings supply worthy foundations for further functional investigation of IbbZIPs , and multiple members may serve as promising regulators to enhance the abiotic stress tolerance of transgenic plants. [ABSTRACT FROM AUTHOR]

• 175 sweetpotato IbANCs were identified and clustered into 22 subgroups including 4 specific subgroups. • Tandem duplications and segmental duplications played critical roles in the diversity of IbANCs. • Collinearity between IbANCs and related orthologs from other plants depicted evolutionary insights into NACs. • Transcriptome and qRT-PCR data provided multiple promising IbNAC regulators for breeding tolerant sweetpotato. • IbNAC006 and IbNAC143 exhibited transactivation activities in yeasts. Sweetpotato is a pivotal crop that can tolerate various edaphic and climatic conditions. The plant-specific NAC transcription factors are involved in regulating various adverse environmental conditions, while currently NAC genes have not been systematically characterized in sweetpotato. Herein, 175 putative NAC or NAC-like genes (IbNACs) were identified in sweetpotato. These genes were unevenly scattered onto all 15 chromosomes, among which 12 pairs of tandem duplications and 12 groups of fragment duplications existed. The collinearity analysis between IbNACs and the related orthologs from nine other plant species further depicted evolutionary insights into NAC gene family. Phylogenetic analysis displayed that IbNAC proteins were classified into 22 subfamilies including four sweetpotato-specific subfamilies, with the support of gene structure and motif analyses. Transcriptome analysis showed that IbNAC genes differed significantly in expression under salt stress, and significant and varying expression of ten selected genes under multiple abiotic stresses was detected by qRT-PCR. Moreover, IbNAC006 and IbNAC143, which were significantly induced by abiotic stress, exhibited obvious transactivation activities, while IbNAC-029/-138/-148 did not. These results will lay the foundation for further evolutionary analysis and functional characterization of IbNACs , particularly with regards to the potential applications of multiple IbNAC regulators in the breeding of tolerant sweetpotato. [ABSTRACT FROM AUTHOR]