Search Results (121)

Among the highly toxic heavy metals, cadmium (Cd) is highlighted as a persistent environmental pollutant, posing serious threats to plants and broader ecological systems. Phytochelatins (PCs), which are synthesized by phytochelatin synthase (PCS), are peptides that play a central role in Cd mitigation through metal chelation and vacuolar sequestration upon formation of Cd-PC complexes. PC synthesis interacts with other cellular mechanisms to shape detoxification outcomes, broadening the functional scope of PCs beyond classical stress responses. Plant Cd-related processes have has been extensively investigated within this context. This perspective article presents key highlights of the panorama concerning strategies targeting the PC pathway and PC synthesis to manipulate Cd-exposed plants. It discusses multiple advances on the topic related to genetic manipulation, including the use of mutants and transgenics, which also covers gene overexpression, PCS-deficient and PCS-overexpressing plants, and synthetic PC analogs. A complementary bibliometric analysis reveals emerging trends and reinforces the need for interdisciplinary integration and precision in genetic engineering. Future directions include the design of multigene circuits and grafting-based innovations to optimize Cd sequestration and regulate its accumulation in plant tissues, supporting both phytoremediation efforts and food safety in contaminated agricultural environments. Full article

Rhodopseudomonas is recognized for its versatile metabolic capabilities that enable it to effectively degrade pollutants and survive various environmental stresses. In this study, we conducted a genome analysis of Rhodopseudomonas sp. P1 to investigate its genetic potential for wastewater treatment processes. Phylogenetic and genome-relatedness analyses confirmed that strain P1 is genetically distinct from other species within the Rhodopseudomonas genus, establishing it as a novel species. The genome sequences obtained and analyzed focused on genes related to carbon and nutrient removal, photosynthetic capabilities, nitrate and nitrite reduction, and the biodegradation of common wastewater pollutants. The identification of wastewater treatment-related genes followed an extensive review of the existing literature that helped in selecting genes involved in various wastewater treatment mechanisms. The genome of Rhodopseudomonas sp. P1 contains a diverse array of genes involved in carbon and nutrient cycling, pollutant biodegradation, and metal resistance, all of which are crucial for its survival in the complex wastewater environment. Specifically, the strain contains genes responsible for the denitrification, nitrogen fixation, sulfur cycling, and detoxification of toxic metals such as copper and arsenic. These findings highlight the potential application of Rhodopseudomonas sp. P1 in wastewater treatment, particularly in environments contaminated with organic pollutants and heavy metals. However, while the genomic features indicate significant promise, the practical implementation of Rhodopseudomonas sp. P1 in real-world wastewater treatment systems will require further investigation, optimization, and validation to fully harness its potential for sustainable and efficient wastewater treatment. Full article

Heavy metal pollution poses a global environmental challenge, with lead (Pb) being particularly concerning due to its persistence and toxicity. This study investigated Xanthium strumarium L. from China’s Yellow River Sanmenxia section through hydroponic experiments (0–600 mg/L Pb²⁺, 1–11 d exposure) to elucidate its Pb²⁺ response mechanisms. Integrated analyses (EDX, FTIR, thermogravimetry, hyperspectral imaging) revealed a three-phase sequestration strategy: the roots immobilized 88.55% of Pb through pectin carboxyl de-esterification and lignin–Pb complexation, while the stems and leaves retained <11.14% and <0.31%, respectively. A critical threshold (300 mg/L) triggered nonlinear Pb accumulation escalation. Thermogravimetric analysis demonstrated enhanced cell wall stability under Pb stress (66.7% residual carbon increase at 600 mg/L). Hyperspectral features (1670 nm band intensity) effectively tracked physiological stress dynamics. The findings establish X. strumarium’s superior suitability for root-based immobilization rather than phytoextraction in Pb-contaminated sites, with its low translocation efficiency minimizing ecological risks. The identified concentration threshold and spectral biomarkers provide multi-scale insights for optimizing in situ phytostabilization strategies, advancing both theoretical understandings and practical applications in heavy metal remediation. Full article

This review provides an in-depth examination of the intricate interactions between plant metabolites and the digestive and antioxidative enzymes in insects, highlighting their essential roles in shaping insect herbivory and adaptation strategies. Plants have evolved a diverse arsenal of secondary metabolites to defend against herbivorous insects, which, in response, have developed sophisticated adaptations to overcome these defenses and efficiently exploit plant resources. We outline the importance of digestive enzymes, such as proteases and amylases, which allow insects to break down complex plant compounds and access vital nutrients. Additionally, the review focuses on antioxidative enzymes in the insect midgut, including superoxide dismutase and catalase, which play a crucial role in mitigating oxidative stress generated during digestion and other metabolic processes. Synthesizing findings from various studies, this review also considers how environmental factors, such as heavy metal exposure and temperature changes, influence these enzymes’ activity levels. It highlights the dual function of antioxidative enzymes in detoxifying harmful plant-derived compounds while preserving cellular stability. The implications of these biochemical interactions for pest management are discussed, with an emphasis on the potential for developing biopesticides that target specific enzymatic pathways to disrupt insect feeding and growth. By elucidating the biochemical mechanisms that underlie plant-insect interactions, this review enhances our understanding of co-evolutionary dynamics and offers insights into sustainable agricultural practices that could leverage these interactions for effective pest control. Finally, the review proposes future research directions aimed at identifying novel plant metabolites with enzyme-modulating properties and exploring the ecological impacts of enzyme-targeted pest management approaches. Full article

Antarctic microorganisms have genomic characteristics and biological functions to ensure survival in complex habitats, potentially representing bioactive compounds of biotechnological interest. Pseudarthrobacter sp. So.54 is an Antarctic bacteria strain isolated from the rhizospheric soil of Colobanthus quitensis. Our work aimed to study its genomic characteristics and metabolic potential, linked to environmental adaptation and the production of secondary metabolites with possible biotechnological applications. Whole-genome sequencing, assembly, phylogenetic analysis, functional annotation, and genomic islands prediction were performed to determine the taxonomic affiliation and differential characteristics of the strain So.54. Additionally, Biosynthetic Gene Clusters (BGCs) responsible for secondary metabolites production were identified. The assembled genome of strain So.54 has 3,871,805 bp with 66.0% G + C content. Phylogenetic analysis confirmed that strain So.54 belongs to the Pseudarthrobacter genus; nevertheless, its nucleotide and amino acid identity values were below the species threshold. The main metabolic pathways and 64 genomic islands associated with stress defense and environmental adaptation, such as heavy metal resistance genes, were identified. AntiSMASH analysis predicted six BGCs with low or no similarity to known clusters, suggesting potential as novel natural products. These findings indicate that strain So.54 could be a novel Pseudarthrobacter species with significant environmental adaptation and biotechnological potential. Full article

The relentless growth of the global population, coupled with increasing biotic and abiotic stresses on crops, poses a major challenge: enhancing agricultural productivity while mitigating these stresses and reducing chemical inputs. Insect farming has led to the large-scale production of insect frass, a nutrient-rich by-product with biofertilizer and biostimulant potential. This review examines the effects of frass on plant stress responses, including its mechanisms of action and possible negative effects. Regarding abiotic stress, frass from certain insects improves plant resilience to drought, waterlogging and salinity, while facilitating heavy metal sorption and complexation in contaminated soils. For biotic stress, frass contains antifungal, antibacterial, and nematicide compounds, as well as entomopathogenic fungi, all of which can reduce pest survival. Additionally, frass activates plant defense mechanisms, such as the increased expression of the defense-related genes involved in stress signaling and immune activation. However, some studies report negative effects, including pathogen dispersion, pest attraction, and the inhibition of beneficial microorganisms commonly used as biopesticides. Despite these risks, frass is a promising alternative for sustainable agriculture, reducing chemical dependency while improving plant resilience. Nevertheless, further research is needed to mitigate its potential risks and optimize its agricultural application. Full article

Cadmium is considered a highly toxic metallic element that does not have any beneficial biological functions for humans or plants. It has been reported that the antagonism of selenium to heavy metal stress has been observed in a variety of plants, and appropriate selenium could alleviate heavy-metal-induced oxidative damage and reduce the accumulation of heavy metals in plants. Changes in physiological characteristics, root tip cells, cadmium concentration, and accumulation of rape under cadmium stress were investigated in this study through pot experiment. Results showed that selenium could alleviate the inhibitory effect of cadmium on the growth of rape seedlings. The concentration and accumulation of cadmium were decreased after the selenium application in rape seeds, ranging from 19.93 to 22.97% and 27.96 to 43.88%, respectively, and the decrease in photosynthetic pigment content induced by cadmium was significantly improved. The results of transmission electron microscopy showed that exogenous selenium and cadmium had metal complexation reaction and formed black precipitation, which may be related to the detoxification effect of selenium on cadmium. More critically, with the addition of selenium, the plasma membrane damage and free radical accumulation in root tips induced by cadmium stress were gradually alleviated in the histochemical staining experiment of rape root tips. These results may provide evidence for exploring effective measures to reduce cadmium accumulation in rape under cadmium-contaminated areas. Full article

Wilson’s disease (WD) is an inherited disorder characterized by abnormal copper metabolism with complex pathological features. Currently, the mechanism of copper overload-induced hepatic injury is unclear. Green tea is a natural chelator, and its main ingredients, green tea polyphenol (GTP) and L-theanine (L-TA) are good at binding to heavy metals like iron and copper. There have been no reports on green tea extracts (GTE) for the treatment of Wilson’s disease. This study investigated the hepatoprotective effect of GTE on WD model mice. Initially, we examined the impact of green tea extract on copper metabolism, excretion, and hepatoprotective effects in WD model toxic milk mice. Then, Ultra performance liquid chromatography (UPLC-DAD) was established to analyze GTP and L-TA in green tea extract. Further screening of eight active components and copper complex active components in green tea extract was carried out by ion analyzer. Finally, we verified the pharmacodynamic effects of these active ingredients at the animal level. The results showed that GTE improves liver function and attenuates liver injury in TX mice by promoting tissue copper excretion and inhibiting oxidative stress, which provides a theoretical basis for green tea’s potential to improve the clinical symptoms of WD. Full article

Plants are subjected to various stresses during the growth process, including biotic stresses, as well as abiotic stresses such as temperature, drought, salt, and heavy metals. To cope with these biotic and abiotic adversities, plants have evolved complex regulatory mechanisms during their long-term environmental adaptations. In a suddenly changing environment, protein modifiers target other proteins to induce post-translational modification (PTM) in order to maintain cell homeostasis and protein biological activity in plants. PTMs modulate the activity of enzymes and transcription factors in their respective metabolic pathways, enabling plants to produce essential compounds for their survival under stress conditions. Examples of post-translational mechanisms include phosphorylation, ubiquitination, glycosylation, acetylation, protein–protein interactions, and targeted protein degradation. Furthermore, the role of histone modifications in regulating secondary metabolism deserves attention due to its potential impact on heritability and its contribution to stress tolerance. Understanding the epigenetic aspect of these modifications can provide valuable insights into the mechanisms underlying stress response. In this context, also examining PTMs that impact the biosynthesis of secondary metabolites is meaningful. Secondary metabolites encompass a wide range of compounds such as flavonoids, alkaloids, and terpenoids. These secondary metabolites play a crucial role in plant defense against herbivores, pathogens, and oxidative stress. In this context, it is imperative to understand the contribution of secondary metabolism to plant tolerance to abiotic stresses and how this understanding can be leveraged to improve long-term survival. While many studies have focused on the transcriptional regulation of these metabolites, there is a growing interest in understanding various changes in PTMs, such as acetylation, glycosylation, and phosphorylation, that are able to modulate plants’ response to environmental conditions. In conclusion, a comprehensive exploration of post-translational mechanisms in secondary metabolism can enhance our understanding of plant responses to abiotic stress. This knowledge holds promise for future applications in genetic improvement and breeding strategies aimed at increasing plant resilience to environmental challenges. Full article

The intensification of global climate change and industrialization has exacerbated abiotic stresses on crops, particularly rice, posing significant threats to food security and human health. The mechanisms by which rice responds to these stresses are complex and interrelated. This review aims to provide a comprehensive understanding of the molecular mechanisms underlying rice’s response to various abiotic stresses, including drought, salinity, extreme temperatures, and heavy metal pollution. We emphasize the molecular mechanisms and structural roles of key proteins involved in these stress responses, such as the roles of SLAC1 and QUAC1 in stomatal regulation, HKT and SOS proteins in salinity stress, heat shock proteins (HSPs) and heat stress transcription factors (HSFs) in temperature stress, and Nramp and ZIP transport proteins in response to heavy metal stress. This review elucidates the complex response networks of rice to various abiotic stresses, highlighting the key proteins and their related molecular mechanisms, which may further help to improve the strategies of molecular breeding. Full article

Plants have evolved complex mechanisms to cope with diverse abiotic stresses, with the phenylpropanoid pathway playing a central role in stress adaptation. This pathway produces an array of secondary metabolites, particularly polyphenols, which serve multiple functions in plant growth, development, regulating cellular processes, and stress responses. Recent advances in understanding the molecular mechanisms underlying phenylpropanoid metabolism have revealed complex regulatory networks involving MYB transcription factors as master regulators and their interactions with stress signaling pathways. This review summarizes our current understanding of polyphenol-mediated stress adaptations in plants, emphasizing the regulation and function of key phenylpropanoid pathway compounds. We discussed how various abiotic stresses, including heat and chilling stress, drought, salinity, light stress, UV radiation, nanoparticles stress, chemical stress, and heavy metal toxicity, modulate phenylpropanoid metabolism and trigger the accumulation of specific polyphenolic compounds. The antioxidant properties of these metabolites, including phenolic acids, flavonoids, anthocyanins, lignin, and polyphenols, and their roles in reactive oxygen species scavenging, neutralizing free radicals, membrane stabilization, and osmotic adjustment are discussed. Understanding these mechanisms and metabolic responses is crucial for developing stress-resilient crops and improving agricultural productivity under increasingly challenging environmental conditions. This review provides comprehensive insights into integrating phenylpropanoid metabolism with plant stress adaptation mechanisms, highlighting potential targets for enhancing crop stress tolerance through metabolic adjustment. Full article

Microplastics (MPs) are emerging pollutants of global concern, while heavy metals such as copper ions (Cu²⁺) are longstanding environmental contaminants with well-documented toxicity. This study investigates the independent and combined effects of polystyrene microplastics (PS-MPs) and Cu on the physiological and biochemical responses of rice seedlings (Oryza sativa L.), a key staple crop. Hydroponic experiments were conducted under four treatment conditions: control (CK), PS-MPs (50 mg·L⁻¹), Cu (20 mg·L⁻¹ Cu²⁺), and a combined PS-MPs + Cu treatment. The results showed that PS-MPs had a slight stimulatory effect on root elongation, while Cu exposure mildly inhibited root growth. However, the combined treatment (PS-MPs + Cu) demonstrated no significant synergistic or additive toxicity on growth parameters such as root, stem, and leaf lengths or biomass (fresh and dry weights). Both PS-MPs and Cu significantly reduced peroxidase (POD) activity in root, stem, and leaf, indicating oxidative stress and disrupted antioxidant defenses. Notably, in the combined treatment, PS-MPs mitigated Cu toxicity by adsorbing Cu²⁺ ions, reducing their bioavailability, and limiting Cu accumulation in rice tissues. These findings reveal a complex interaction between MPs and heavy metals in agricultural systems. While PS-MPs can alleviate Cu toxicity by reducing its bioavailability, they also compromise antioxidant activity, potentially affecting plant resilience to stress. This study provides a foundation for understanding the combined effects of MPs and heavy metals, emphasizing the need for further research into their long-term environmental and agronomic impacts. Full article

Microbial adsorption is a cost-effective and environmentally friendly remediation method for heavy metal pollution. The adsorption mechanism of cadmium (Cd) by bacteria inhabiting extreme environments is largely unexplored. This study describes the biosorption of Cd²⁺ by Sphingomonas sp. M1-B02, which was isolated from the moraine on the north slope of Mount Everest and has a good potential for biosorption. The difference in Cd²⁺ adsorption of the strain after UV irradiation stimulation indicated that the adsorption reached 68.90% in 24 h, but the adsorption after UV irradiation increased to 80.56%. The genome of strain M1-B02 contained antioxidant genes such as mutL, recA, recO, and heavy metal repair genes such as RS14805, apaG, chrA. Hydroxyl, nitro, and etceteras bonds on the bacterial surface were involved in Cd²⁺ adsorption through complexation reactions. The metabolites of the strains were significantly different after 24 h of Cd²⁺ stress, with pyocyanin, L-proline, hypoxanthine, etc., being downregulated and presumably involved in Cd²⁺ biosorption and upregulated after UV-C irradiation, which may explain the increase in Cd²⁺ adsorption capacity of the strain after UV-C irradiation, while the strain improved the metabolism of the antioxidant metabolite carnosine, indirectly increasing the adsorption capacity of the strains for Cd²⁺. Full article

With the increasing concern on heavy metal contamination in agriculture and other environmental settings, unraveling the mechanisms of cadmium (Cd) tolerance and response in plants has become highly important. Ongoing plant Cd research over the years has focused on strategic and relevant aspects, including molecular, biochemical, and physiological processes. From this perspective, phosphoproteomics appears to be an innovative and powerful approach to investigating plant responses to Cd stress. Here, we summarize progress in plant Cd research across different plant species regarding large-scale phosphoproteomic investigations. Some studies revealed major proteins participating in detoxification, stress signaling, and metabolism, along with their regulation through phosphorylation, which modulates the plant’s defense against Cd. However, many pathways remain unexplored. Expanding these studies will help our ability to alleviate Cd stress and provide further information concerning involved mechanisms. Our purpose is to inspire researchers to further explore the use of phosphoproteomics in unraveling such complex mechanisms of Cd tolerance and response across various plant species, with the ultimate aim of enhancing strategies for mitigating Cd stress in agriculture and polluted environments. Full article

Heavy metal pollution is one of the most devastating abiotic factors, significantly damaging crops and human health. One of the serious problems it causes is a rise in cadmium (Cd) toxicity. Cd is a highly toxic metal with a negative biological role, and it enters plants via the soil–plant system. Cd stress induces a series of disorders in plants’ morphological, physiological, and biochemical processes and initiates the inhibition of seed germination, ultimately resulting in reduced growth. Fiber crops such as kenaf, jute, hemp, cotton, and flax have high industrial importance and often face the issue of Cd toxicity. Various techniques have been introduced to counter the rising threats of Cd toxicity, including reducing Cd content in the soil, mitigating the effects of Cd stress, and genetic improvements in plant tolerance against this stress. For decades, plant breeders have been trying to develop Cd-tolerant fiber crops through the identification and transformation of novel genes. Still, the complex mechanism of Cd tolerance has hindered the progress of genetic breeding. These crops are ideal candidates for the phytoremediation of heavy metals in contaminated soils. Hence, increased Cd uptake, accumulation, and translocation in below-ground parts (roots) and above-ground parts (shoots, leaves, and stems) can help clean agricultural lands for safe use for food crops. Earlier studies indicated that reducing Cd uptake, detoxification, reducing the effects of Cd stress, and developing plant tolerance to these stresses through the identification of novel genes are fruitful approaches. This review aims to highlight the role of some conventional and molecular techniques in reducing the threats of Cd stress in some key fiber crops. Molecular techniques mainly involve QTL mapping and GWAS. However, more focus has been given to the use of transcriptome and TFs analysis to explore the potential genomic regions involved in Cd tolerance in these crops. This review will serve as a source of valuable genetic information on key fiber crops, allowing for further in-depth analyses of Cd tolerance to identify the critical genes for molecular breeding, like genetic engineering and CRISPR/Cas9. Full article