Polycyclic aromatic hydrocarbons (PAHs) are a class of organic pollutants widely present in various environmental media. Some PAHs have carcinogenic, teratogenic, and mutagenic effects. Urban lakes are severely polluted by PAHs due to human activities.
View Article and Find Full Text PDFTo meet the challenge of water quality protection and management in the middle Yangtze River and understand the accumulation mechanism of PAHs in aquatic complexity systems, caused by hydro-chemical changes, anthropogenic and geological activities, and intensive surface water-groundwater interaction, a comprehensive study is urgently needed. The study investigated the pollution levels, potential sources, accumulation mechanism, and groundwater- surface water interaction of polycyclic aromatic hydrocarbons (PAHs) in wet and dry seasons of the middle Yangtze River. There was no significant difference of PAHs accumulation between wet and dry seasons of the middle Yangtze River.
View Article and Find Full Text PDFAs sessile organisms, the plant immune system plays a vital role in protecting plants from the widespread pathogens in the environment. The (Arabidopsis) receptor-like cytoplasmic kinase BOTRYTIS-INDUCED KINASE1 (BIK1) acts as a central regulator during plant immunity. As such, not only the BIK1 protein accumulation but also the attenuation is tightly regulated to ensure effective immune responses.
View Article and Find Full Text PDFHydrogel biosensors present numerous advantages in food safety analysis owing to their remarkable biocompatibility, cargo-loading capabilities and optical properties. However, the current drawbacks (slow target responsiveness and poor mechanical strength) restricted their further utilization at on-site detection of targets. To address these challenges, a DNA-functionalized cryogel with hierarchical pore structures is constructed to improve the reaction rate and the robustness of hydrogel biosensor.
View Article and Find Full Text PDFHerein, a sensitive biosensor is constructed based on a novel rolling circle amplification (RCA) for colorimetric quantification of lead ion (Pb). At the detection system, GR5 DNAzymes are modified on the surface of an immunomagnetic bead, and Pb is captured by the aptamer, inducing the disintegration of the GR5 DNAzyme and the release of the DNA walker. After the introduction of the template DNA, T4 DNA ligase, and phi29 DNA polymerase, an RCA is initiated for the sensitivity improvement of this method.
View Article and Find Full Text PDFPathogen-associated molecular patterns (PAMPs) trigger plant innate immunity that acts as the first line of inducible defense against pathogen infection. A receptor-like cytoplasmic kinase BOTRYTIS-INDUCED KINASE 1 (BIK1) functions as a signaling hub immediately downstream of multiple pattern recognition receptors (PRRs). It is known that PLANT U-BOX PROTEIN 25 (PUB25) and PUB26 ubiquitinate BIK1 and mediate BIK1 degradation.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2023
Stomatal movements allow the uptake of CO for photosynthesis and water loss through transpiration, therefore play a crucial role in determining water use efficiency. Both red and blue lights induce stomatal opening, and the stomatal apertures under light are finetuned by both positive and negative regulators in guard cells. However, the molecular mechanisms for precisely adjusting stomatal apertures under light have not been completely understood.
View Article and Find Full Text PDFRadiocesium remediation is of great significance for the sustainable development of nuclear energy and ecological protection. It is very challenging for the effective recovery of Cs from aqueous solutions due to its strong radioactivity, solubility and mobility. Herein, the efficient recovery of Cs ions has been achieved by three layered vanadyl oxalatophosphates, namely (NH)[(VO)(HPO)CO]·5 HO (NVPC), Na[(VO)(HPO)CO]·2 HO (SVPC), and K[(VO)(HPO)(PO)(CO)]·4.
View Article and Find Full Text PDFImmune responses are triggered when pattern recognition receptors recognize microbial molecular patterns. The Arabidopsis (Arabidopsis thaliana) receptor-like cytoplasmic kinase BOTRYTIS-INDUCED KINASE1 (BIK1) acts as a signaling hub of plant immunity. BIK1 homeostasis is maintained by a regulatory module in which CALCIUM-DEPENDENT PROTEIN KINASE28 (CPK28) regulates BIK1 turnover via the activities of two E3 ligases.
View Article and Find Full Text PDFTetrabromobisphenol A (TBBPA) is a kind of brominated flame retardant that is usually added to products to reduce their flame retardancy. However, its extensive use has resulted in their residues being found in the environment, which is very harmful. Herein, an indirect competitive immunosensor has been established for TBBPA detection based on the signal amplification system.
View Article and Find Full Text PDFACS Appl Mater Interfaces
March 2021
The need to effectively and selectively remove radioactive Cs and Sr from nuclear waste solutions persists to mitigate their environmental mobility and high radiotoxicity. Because it is difficult to effectively remove them from acidic environments that degrade most sorbents, new sorbent materials are highly desirable. Here, efficient removal of Cs and Sr is achieved by the composite of layered tin sulfide (MeNH)(MeNH)SnS·1.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2020
Plant innate immunity varies with age and plant developmental stages. Recently, we reported that Arabidopsis thaliana microRNA miR172b regulates FLS2 transcription through two transcription factors: TARGET OF EAT1 (TOE1) and TOE2. Although the flg22-triggered immune responses were investigated in 2-d-old or even younger toe1/toe2 mutant and miR172b over expression (OE) transgenic plants, the FLS2-mediated immune responses in older plants remain uncharacterized yet.
View Article and Find Full Text PDFA simple indirectly competitive ratiometric fluorescent immunoassay was designed based on fluorescein amidite (FAM)-DNA-functionalized CdSe/ZnS quantum dots (QDs) for the sensitive determination of tetrabromobisphenol A (TBBPA). At the detection system, catalase (CAT) was labeled on the secondary antibody (Ab), which served as a controller of the HO concentration. After the competitive binding step, the emitted red fluorescence (excitation at 490 nm) from FAM-DNA-functionalized CdSe/ZnS QDs could be effectively quenched by the HO added.
View Article and Find Full Text PDFHere, a novel chemiluminescence (CL) immunoassay was fabricated for sensitive determination of tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA-DHEE), one of typical tetrabromobisphenol A derivatives. At the indirectly competitive method, the synthesized PS@hemin@Co was labelled by secondary antibody (Ab) instead of common natural enzymes, which showed excellent catalysis towards the decomposition of luminol-HO for producing CL signal. Furthermore, the CL signal was greatly amplified owing to the synergistic catalysis of hemin and Co in the detection system.
View Article and Find Full Text PDFNanozymes with peroxidase-like activity have been widely used as signal labels in electrochemical immunosensors. However, these sensors always suffer from some shortcomings during the processes underlying nanozyme labeling, including complex reactions, nanozyme inactivation after being decorated on the antibodies. To solve these problems, a novel electrochemical immunosensor was designed for ultrasensitive detection of sulfonamides (SAs), in which the synthesized 2D Cu-TCPP(Fe) with peroxidase-like property was used as a nanozyme that was directly modified on the electrode surface.
View Article and Find Full Text PDFThe plant hormones brassinosteroids (BRs) modulate plant growth and development. Cysteine (Cys) residues located in the extracellular domain of a protein are of importance for protein structure by forming disulfide bonds. To date, the systematic study of the functional significance of Cys residues in BR-insensitive 1 (BRI1) is still lacking.
View Article and Find Full Text PDFA novel chemiluminescence immunoassay based on luminol-modified gold nanoclusters (AuNCs@Peps@luminol) was developed for simultaneous detection of tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA-DHEE) and tetrabromobisphenol A mono(hydroxyethyl) ether (TBBPA-MHEE), an important derivative and byproduct of tetrabromobisphenol A (TBBPA), respectively. In the system, alkaline phosphatase (ALP) was labeled on the second antibody (Ab) for signal amplification. When ALP-Ab was captured by antigen-primary antibody (Ab) complex, disodium phenyl phosphate (PPNa) generated massive phenol under the catalysis of ALP, markedly inhibiting the chemiluminescence intensity of AuNCs@Peps@luminol.
View Article and Find Full Text PDFA sensitive and artful colorimetric immunosensor based on horseradish peroxidase (HRP) was designed by labelling metal-organic frameworks (Cu-MOFs) on the second antibody (Cu-MOFs@Ab) as signal amplification for the detection of trace dibutyl phthalate (DBP). In this system, when Cu-MOFs@Ab was captured by antigen- primary antibody (Ab) complex, tremendous Cu(II) will be released from Cu-MOFs in the presence of nitric acid (HNO), and Cu(II) will be further reduced to Cu(I) after the addition of sodium ascorbate (SA), consequently, inhibiting the HRP to catalyse the colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (ox TMB). Under the optimized conditions, the limit of detection (LOD) was 1 μg L, which was almost 60 times lower than that using a conventional ELISA with the same antibody.
View Article and Find Full Text PDFA novel, competitive, enzyme-linked immunosorbent assay (ELISA) was presented in this paper based on the inhibition of catalysis of AuNCs@BSA triggered by dissolved Ag for the detection of dibutyl phthalate (DBP). In the immunoassay system, numerous Ag was released from AgNPs (labelled on the second antibody, AgNPs@Ab) in the presence of HO after the competition step, preventing AuNCs@BSA from inducing a color change of 3,3',5,5'-tetramethylbenzidine (TMB) to blue. Due to the signal amplification by the principle, the sensitivity of the modified ELISA was improved with the low limit of detection (LOD) of 4.
View Article and Find Full Text PDFOn the basis of HO-mediated growth of gold nanoparticle (AuNPs), a novel plasmonic enzyme-linked immunosorbent assay (pELISA) was developed with a polyclonal antibody for the ultrasensitive simultaneous naked-eye detection of tetrabromobisphenol A bis(2-hydroxyetyl) ether (TBBPA DHEE) and tetrabromobisphenol A mono(hydroxyethyl) ether (TBBPA MHEE), one of the major derivatives and byproducts of tetrabromobisphenol A (TBBPA), respectively. In this modified indirect competitive pELISA, glucose oxidase (GOx) played an important role leading to the growth of AuNPs through a reaction between GOx and glucose to produce hydrogen peroxide (HO). In addition, further signal amplification was achieved via a large number of GOx molecules, which were immobilized on silica nanoparticles carrying poly brushes (SiO@PAA) to increase the enzyme load, and the whole complex was conjugated on the second antibody.
View Article and Find Full Text PDFArabidopsis AVRPPHB SUSCEPTIBLE1 (PBS1) serves as a "decoy" in activating RESISTANCE TO PSEUDOMONAS SYRINGAE5 (RPS5) upon cleavage by Pseudomonas phaseolicola B (AvrPphB), a Pseudomonas syringae effector. The SEMPH motif in PBS1 was thought to allow it to be distinguished by RPS5 from the closely related Arabidopsis kinases. However, the underlying mechanism is not fully understood.
View Article and Find Full Text PDFOur previous study revealed that the antioxidant activity of polysaccharide (coded as FGFP) extracted from by enzymolysis treatment was significantly superior than that (coded as GFP) extracted by boiling-water. In this study, one purified polysaccharide fractions (coded as FGFP-11) was obtained from FGFP by purified using DEAE-52 column and Sephacryl S-500HR column. Results indicated that FGFP-11 with MW of 59.
View Article and Find Full Text PDFCurrently, there is limited information on the toxicity of low concentration of metal mixtures in the environment. Of particular interest is the effect of low levels of metal mixtures on neurodevelopment of aquatic organisms. This study reports the neurological gene expressions after exposing zebrafish embryos to low concentration toxic heavy metals, 120 h post fertilization (hpf).
View Article and Find Full Text PDF