Exogenous Inducers Research Articles

Improving the Characteristics of Fruiting Bodies in Lentinus edodes: The Impact of Rolipram-Induced cAMP Modulation.

Background: Strains XG04 and XGT2 of Lentinus edodes (Berk.) Singer demonstrate a high degree of genomic similarity, with XGT2 representing a systematic selection of XG04 and exhibiting enhanced phenotypic traits. Methods: An investigation into the differences between these strains was conducted using untargeted metabolomics to identify potential causal factors. Five exogenous inducers were assessed for their relationship with the observed phenotypes, and their impacts on fruiting body characteristics were analyzed. Results: Notably, the exogenous inducer rolipram, at a concentration of 0.4%, was found to increase cAMP expression levels in L. edodes primordia, which subsequently affected gill development, leading to the formation of gill-free fruiting bodies. Morphological differences between the two strains were evident; XG04 exhibited a spherical morphology with absent gills, rendering it commercially unviable, whereas XGT2 displayed a thicker cap and a more robust stipe, maintaining its characteristic umbrella shape. Conclusions: As the concentration of rolipram increased, both cap retraction and gill reduction in XGT2 occurred in a dose-dependent manner. The endogenous cAMP levels in the fruiting bodies were measured before and after rolipram treatment, revealing that the cap retraction and gill reduction in XGT2 progressed in a dose-dependent manner alongside increasing cAMP expression levels. Furthermore, a positive correlation was observed between cAMP levels and rolipram concentration. This study provides a foundation for improving the quality and productivity of mushroom cultivation by manipulating fruiting body characteristics through external stimuli.

Medium acidosis drives cardiac differentiation during mesendoderm cell fate specification from human pluripotent stem cells

Effective lineage-specific differentiation is essential to fulfilling the great potentials of human pluripotent stem cells (hPSCs). In this report, we investigate how modulation of medium pH and associated metabolic changes influence mesendoderm differentiation from hPSCs. We show that daily medium pH fluctuations are critical for the heterogeneity of cell fates in the absence of exogenous inducers. Acidic environment alone leads to cardiomyocyte generation without other signaling modulators. In contrast, medium alkalinization is inhibitory to cardiac fate even in the presence of classic cardiac inducers. We then demonstrate that acidic environment suppresses glycolysis to facilitate cardiac differentiation, while alkaline condition promotes glycolysis and diverts the differentiation toward other cell types. We further show that glycolysis inhibition or AMPK activation can rescue cardiac differentiation under alkalinization, and glycolysis inhibition alone can drive cardiac cell fate. This study highlights that pH changes remodel metabolic patterns and modulate signaling pathways to control cell fate.

Effect of exogenous sperm capacitation inducers on stallion sperm

Although under appropriate laboratory conditions, sperm from different mammalian species can be capacitated in vitro, the optimal conditions for sperm capacitation in the stallion have been elusive. This study evaluated the effect of different capacitating inducers in Whitten and Tyrode media and assessed their impact on capacitation-related factors. Stallion sperm were incubated with different combinations of capacitating inducers at 38.5 °C in an air atmosphere. Sperm quality variables such as motility, mitochondrial membrane potential, and lipid peroxidation were assessed. Membrane fluidity and intracellular calcium levels were evaluated as early markers of capacitation, while tyrosine phosphorylation events and the sperm's ability to perform acrosomal exocytosis were used as late capacitation markers. Finally, these sperm were evaluated using a heterologous zona pellucida binding assay. The findings confirm that capacitating conditions evaluated increase intracellular calcium levels and membrane fluidity in both media. Similarly, including 2 or 3 inducers in both media increased tyrosine phosphorylation levels and acrosomal exocytosis after exposure to progesterone, confirming that stallion sperm incubated in these conditions shows cellular and molecular changes consistent with sperm capacitation. Furthermore, the zona pellucida binding assay confirmed the binding capacity of sperm incubated in capacitation conditions, a key step for stallion in vitro fertilization success. Further studies are needed to evaluate the effect of these conditions on in vitro fertilization in the horse.

Optimization of Recombinant Protein Production in Synechococcus elongatus PCC 7942: Utilizing Native Promoters and Magnetic Fields.

The cyanobacterium Synechococcus elongatus PCC 7942 holds significant potential as a biofactory for recombinant protein (RP) production due to its capacity to harness light energy and utilize CO2. This study aimed to enhance RP production by integration of native promoters and magnetic field application (MF) in S. elongatus PCC 7942. The psbA2 promoter, which responds to stress conditions, was chosen for the integration of the ZsGreen1 gene. Results indicated successful gene integration, affirming prior studies that showed no growth alterations in transgenic strains. Interestingly, exposure to 30 mT (MF30) demonstrated a increase in ZsGreen1 transcription under the psbA2 promoter, revealing the influence of MF on cyanobacterial photosynthetic machinery. This enhancement is likely attributed to stress-induced shifts in gene expression and enzyme activity. MF30 positively impacted photosystem II (PSII) without disrupting the electron transport chain, aligning with the "quantum-mechanical mechanism" theory. Notably, fluorescence levels and gene expression with application of 30 mT were significantly different from control conditions. This study showcases the efficacy of utilizing native promoters and MF for enhancing RP production in S. elongatus PCC 7942. Native promoters eliminate the need for costly exogenous inducers and potential cell stress. Moreover, the study expands the scope of optimizing RP production in photoautotrophic microorganisms, providing valuable insights for biotechnological applications.

Electroconductive Nanofibrous Scaffolds Enable Neuronal Differentiation in Response to Electrical Stimulation without Exogenous Inducing Factors.

Among the various biochemical and biophysical inducers for neural regeneration, electrical stimulation (ES) has recently attracted considerable attention as an efficient means to induce neuronal differentiation in tissue engineering approaches. The aim of this in vitro study was to develop a nanofibrous scaffold that enables ES-mediated neuronal differentiation in the absence of exogenous soluble inducers. A nanofibrous scaffold composed of polycaprolactone (PCL), poly-L-lactic acid (PLLA), and single-walled nanotubes (SWNTs) was fabricated via electrospinning and its physicochemical properties were investigated. The cytocompatibility of the electrospun composite with the PC12 cell line and bone marrow-derived mesenchymal stem cells (BMSCs) was investigated. The results showed that the PCL/PLLA/SWNT nanofibrous scaffold did not exhibit cytotoxicity and supported cell attachment, spreading, and proliferation. ES was applied to cells cultured on the nanofibrous scaffolds at different intensities and the expression of the three neural markers (Nestin, Microtubule-associated protein 2, and β tubulin-3) was evaluated using RT-qPCR analysis. The results showed that the highest expression of neural markers could be achieved at an electric field intensity of 200 mV/cm, suggesting that the scaffold in combination with ES can be an efficient tool to accelerate neural differentiation in the absence of exogenous soluble inducers. This has important implications for the regeneration of nerve injuries and may provide insights for further investigations of the mechanisms underlying ES-mediated neuronal commitment.

Adaptive β-lactam resistance from an inducible efflux pump that is post-translationally regulated by the DjlA co-chaperone.

The acquisition of multidrug resistance (MDR) determinants jeopardizes treatment of bacterial infections with antibiotics. The tripartite efflux pump AcrAB-NodT confers adaptive MDR in the polarized α-proteobacterium Caulobacter crescentus via transcriptional induction by first-generation quinolone antibiotics. We discovered that overexpression of AcrAB-NodT by mutation or exogenous inducers confers resistance to cephalosporin and penicillin (β-lactam) antibiotics. Combining 2-step mutagenesis-sequencing (Mut-Seq) and cephalosporin-resistant point mutants, we dissected how TipR uses a common operator of the divergent tipR and acrAB-nodT promoter for adaptive and/or potentiated AcrAB-NodT-directed efflux. Chemical screening identified diverse compounds that interfere with DNA binding by TipR or induce its dependent proteolytic turnover. We found that long-term induction of AcrAB-NodT deforms the envelope and that homeostatic control by TipR includes co-induction of the DnaJ-like co-chaperone DjlA, boosting pump assembly and/or capacity in anticipation of envelope stress. Thus, the adaptive MDR regulatory circuitry reconciles drug efflux with co-chaperone function for trans-envelope assemblies and maintenance.

An Intelligent Synthetic Bacterium for Chronological Toxicant Detection, Biodegradation, and Its Subsequent Suicide.

Modules, toolboxes, and synthetic biology systems may be designed to address environmental bioremediation. However, weak and decentralized functional modules require complex control. To address this issue, an integrated system for toxicant detection and biodegradation, and subsequent suicide in chronological order without exogenous inducers is constructed. Salicylic acid, a typical pollutant in industrial wastewater, is selected as an example to demonstrate this design. Biosensors are optimized by regulating the expression of receptors and reporters to get 2-fold sensitivity and 6-fold maximum output. Several stationary phase promoters are compared, and promoter Pfic is chosen to express the degradation enzyme. Two concepts for suicide circuits are developed, with the toxin/antitoxin circuit showing potent lethality. The three modules are coupled in a stepwise manner. Detection and biodegradation, and suicide are sequentially completed with partial attenuation compared to pre-integration, except for biodegradation, being improved by the replacements of ribosome binding site. Finally, a long-term stability test reveals that the engineered strain maintained its function for ten generations. The study provides a novel concept for integrating and controlling functional modules that can accelerate the transition of synthetic biology from conceptual to practical applications.

Transcriptional Responses for Biosynthesis of Triterpenoids in Exogenous Inducers Treated Inonotus Hispidus Using RNA-Seq

Inonotus hispidus is a traditional medicinal that grows in Northeast China and produces various economically important compounds, including polysaccharide compounds and terpenoids; triterpenoid saponins is the main bioactive component. Our research group has found that the accumulation of triterpenoid was affected by exogenous inducers. Experimental results showed that treatment with methyl jasmonate (MeJA) and oleic acid significantly increased the triterpenoid content of I. hispidus. However, how exogenous inducers enhance production of secondary metabolites in I. hispidus is not well understood. In this study, metabolite changes were further investigated with UPLC-TOF/MS following exogenous inducer treatment. As a result, a total of eight types of triterpenoids in I. hispidus were identified. The RNA-seq analysis was used to evaluate the effects of exogenous inducers on the expression of triterpenoid-synthesis-related genes in I. hispidus in liquid fermentation. This study is the first exploration to profile the transcriptome of I. hispidus after adding exogenous inducers; the generated data and gene will facilitate further molecular studies on the physiology and metabolism in this fungi. By comparative transcriptomic analysis, a series of candidate genes involved in the biosynthetic pathway of triterpenoids are identified, providing new insights into their biosynthesis at the transcriptome level.

The Human Cytomegalovirus β2.7 Long Non-Coding RNA Prevents Induction of Reactive Oxygen Species to Maintain Viral Gene Silencing during Latency.

Human cytomegalovirus (HCMV) is a significant source of disease for the immunosuppressed and immunonaive. The treatment of HCMV is made more problematic by viral latency, a lifecycle stage in which the virus reduces its own gene expression and produces no infectious virus. The most highly expressed viral gene during HCMV latency is the viral β2.7 long non-coding RNA. Although we have recently shown that the β2.7 lncRNA lowers levels of reactive oxygen species (ROS) during infection in monocytes, how this impacts latency is unclear. We now show that β2.7 is important for establishing and maintaining HCMV latency by aiding the suppression of viral lytic gene expression and that this is directly related to its ability to quench reactive oxygen species (ROS). Consistent with this, we also find that exogenous inducers of ROS cause reactivation of latent HCMV. These effects can be compensated by treatment with an antioxidant to lower ROS levels. Finally, we show that ROS-mediated reactivation is independent of myeloid differentiation, but instead relies on NF-κB activation. Altogether, these results reveal a novel factor that is central to the complex process that underpins HCMV latency. These findings may be of particular relevance in the transplant setting, in which transplanted tissue/organs are subject to very high ROS levels, and HCMV reactivation poses a significant threat.

Heterogeneous Nature of Trained Innate Immune Cells in Health and Disease.

Heterogeneous Nature of Trained Innate Immune Cells in Health and Disease.

Effect of exogenous additives and stress inducers on xylitol production by Debaryomyces nepalensis in batch culture

AbstractThe present study investigates various strategies to improve the production of xylitol, a platform chemical, by batch cultivation of Debaryomyces nepalensis. Enhancement of xylitol production via triggerring its biosynthetic pathway in yeast cells was carried out under varied initial phosphate concentrations of the medium and by the addition of stress inducers and co‐substrates. Among the tested phosphate concentrations, the xylitol production was found to be increased by 1.62‐fold at limited initial phosphate concentration (1.5 g L−1). Similarly, among all of the studied co‐substrates, the xylitol production was found to be enhanced by adding 10% maltose at the start of fermentation. Among the different stress inducers tested, addition of hydrogen peroxide and sodium hypochlorite at low concentration (10 ppm) resulted in improved xylitol yields by 28 and 34%, respectively, when compared with the control. De facto stress inducers and nutrient limitations may be worthy of consideration to enhance the production of xylitol in batch culture. We envision that the addition of stress inducers at minimum dosage will enhance xylitol productivity. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd

Cellular Senescence: Molecular Targets, Biomarkers, and Senolytic Drugs.

Cellular senescence is defined as irreversible cell cycle arrest caused by various processes that render viable cells non-functional, hampering normal tissue homeostasis. It has many endogenous and exogenous inducers, and is closely connected with age, age-related pathologies, DNA damage, degenerative disorders, tumor suppression and activation, wound healing, and tissue repair. However, the literature is replete with contradictory findings concerning its triggering mechanisms, specific biomarkers, and detection protocols. This may be partly due to the wide range of cellular and in vivo animal or human models of accelerated aging that have been used to study senescence and test senolytic drugs. This review summarizes recent findings concerning senescence, presents some widely used cellular and animal senescence models, and briefly describes the best-known senolytic agents.

Electrogenetic Signal Transmission and Propagation in Coculture to Guide Production of a Small Molecule, Tyrosine.

There are many strategies to actuate and control genetic circuits, including providing stimuli like exogenous chemical inducers, light, magnetic fields, and even applied voltage, that are orthogonal to metabolic activity. Their use enables actuation of gene expression for the production of small molecules and proteins in many contexts. Additionally, there are a growing number of reports wherein cocultures, consortia, or even complex microbiomes are employed for the production of biologics, taking advantage of an expanded array of biological function. Combining stimuli-responsive engineered cell populations enhances design space but increases complexity. In this work, we co-opt nature's redox networks and electrogenetically route control signals into a consortium of microbial cells engineered to produce a model small molecule, tyrosine. In particular, we show how electronically programmed short-lived signals (i.e., hydrogen peroxide) can be transformed by one population and propagated into sustained longer-distance signals that, in turn, guide tyrosine production in a second population building on bacterial quorum sensing that coordinates their collective behavior. Two design methodologies are demonstrated. First, we use electrogenetics to transform redox signals into the quorum sensing autoinducer, AI-1, that, in turn, induces a tyrosine biosynthesis pathway transformed into a second population. Second, we use the electrogenetically stimulated AI-1 to actuate expression of ptsH, boosting the growth rate of tyrosine-producing cells, augmenting both their number and metabolic activity. In both cases, we show how signal propagation within the coculture helps to ensure tyrosine production. We suggest that this work lays a foundation for employing electrochemical stimuli and engineered cocultures for production of molecular products in biomanufacturing environments.

Technology and Application of Hairy Root Culture in Monocotyledons

Background: Hairy root culture has been widely used in the production of metabolites in dicotyledons, and a large number of food crops and medicinal plants in monocotyledons need to be developed. However, there are many difficulties in the induction of hairy roots in monocotyledons. The purpose of this paper is to introduce the inducing methods, influencing factors, and application of hairy roots in monocotyledons, and to promote the development of hairy root system in monocotyledons. Methods: The mechanism of action of Agrobacterium rhizogenes and the current situation of hairy root induction, induction methods and influencing factors of monocotyledons were summarized to provide convenience for efficient acquisition of hairy root of monocotyledons. Results: Monocotyledons are not easy to produce phenols. Cells are prone to lignification, adverse differentiation and selective response to Agrobacterium rhizogenes strains. It is proposed that before induction, plant varieties and explants should be selected, and different infection strains should be screened. In the process of hairy root induction, exogenous inducers such as acetosyringone can be added. Although these factors can provide some help for the induction of hairy roots in monocotyledons, we still need to pay attention to the disadvantages of monocotyledons from dicotyledons at the cellular level. Conclusion: A large number of food crops and medicinal plants are monocotyledons. Hairy root culture can be used to help the breeding and production of medicinal substances. Therefore, it is necessary to pay attention to the selection of varieties and explants, the selection of Agrobacterium rhizogenes and the addition of acetosyringone in the process of hairy root induction to improve the production efficiency and facilitate the development and utilization of monocotyledons.

Mechanism of chromosome rearrangement arising from single-strand breaks

Chromosome rearrangements, which are structural chromosomal abnormalities commonly found in human cancer, result from the misrejoining between two or more DNA double-strand breaks arising at different genomic regions. Consequently, chromosome rearrangements can generate fusion genes that promote tumorigenesis. The mechanisms of chromosome rearrangement have been studied using exogenous double-strand break inducers, such as radiation and nucleases. However, the mechanism underlying the occurrence of chromosome rearrangements in the absence of exogenous double-strand break-inducing stimuli is unclear. This study aimed to identify the major source of chromosome rearrangements and the DNA repair pathway that suppresses them. DNA repair factors that potentially suppress gene fusion were screened using The Cancer Genome Atlas dataset. In total, 22 repair factors whose expression levels were negatively correlated with the frequency of gene fusion were identified. More than 60% of these repair factors are involved in homologous recombination, a major double-strand break repair pathway. We hypothesized that DNA single-strand breaks are the source of double-strand breaks that lead to chromosome rearrangements. This study demonstrated that hydrogen peroxide (H2O2)-induced single-strand breaks gave rise to double-strand breaks in a replication-dependent manner. Additionally, H2O2 induced the formation of RPA and RAD51 foci, which indicated that double-strand breaks derived from single-strand breaks were repaired through homologous recombination. Moreover, treatment with H2O2 promoted the formation of radial chromosomes, a type of chromosome rearrangements, only upon the downregulation of homologous recombination factors, such as BRCA1 and CtIP. Thus, single-strand breaks are the major source of chromosome rearrangements when the expression of homologous recombination factors is downregulated.

High-efficiency production of 5-aminovalerate in engineered Escherichia coli controlled by an anaerobically-induced nirB promoter

Biobased production of 5-aminovalerate (5AVA) from biomass can support a sustainable and economic biorefinery process to produce bio-based nylon 5 for food packaging materials. Cost-competitive production of 5AVA from biomass is a key factor in the successful commercialization of nylon 5. Bioproduction of 5AVA is a promising candidate for the industrial process to the current petrochemical route. In this study, we developed an artificial 2-keto-6-aminocaproate-mediated pathway for cost-competitive and high efficiency production of 5AVA in engineered Escherichia coli. Firstly, the combination of native l-lysine α-oxidase (RaiP) from Scomber japonicas, α-ketoacid decarboxylase (KivD) from Lactococcus lactis and aldehyde dehydrogenase (PadA) from Escherichia coli could efficiently convert l-lysine into 5AVA. Moreover, the engineered strains ML03-PnirB-RKP, ML03-PPL-PR-RKP, ML03-PM1-93-RKP induced by anaerobic condition, temperature-induced, constitutive expression instead of expensive isopropyl β-D-thiogalactoside were constructed, respectively. The use of nirB promoter induced by anaerobic condition not only could attain a higher titer of 5AVA than PL-PR and M1-93 promoters, but omit cost of expensive exogenous inducers. After the replacement of industrial materials, 5AVA titer successfully reached 33.68 g/L in engineered strain ML03-PnirB-RKP via biotransformation. This biotransformation process conduces to the cosmically industrial 5AVA bioproduction.

ФИЗИОЛОГО-БИОХИМИЧЕСКИЕ ХАРАКТЕРИСТИКИ МИКРОПОБЕГОВ ЧАЯ (Camellia sinensis L.) В УСЛОВИЯХ in vitro: НОРМА, ОСМОТИЧЕСКИЙ СТРЕСС, ВЛИЯНИЕ КАЛЬЦИЯ

Stress tolerance is an important trait, that determines the productivity of plants under drought, hypothermia, mineral deficiency, and salinity. Numerous studies of various agricultural crops (J.K. Zhu, 2016; E. Fleta-Soriano, S. Munné-Bosch, 2016), including tea crop (Camellia sinensis L.), were aimed at solving this problem due to the global aridization of the climate. (T.K. Maritim et al., 2015; L.S. Samarina et al., 2019). Along with the sufficiently detailed physiological, biochemical and molecular studies of tea drought tolerance, the exogenous regulation of tolerance by using of chemical and biological substances is still not investigated. In addition, the important role of calcium ions (Ca2+) in the cell recognition of an external stressor by the triggering signal transduction has been shown in many crops (M.C. Kim, 2009; E.G. Rikhvanov et al., 2014). In these studies, tissue culture media supplemented with the osmotically active substances (R.M. Pérez-Clemente et al., 2012; M.K. Rai et al., 2011) and artificial biosystems (microshoots and tissues in vitro), are often used as “drought models” to reveal cellular adaptation mechanisms. However, just a few studies were conducted aimed at deciphering the biochemical and molecular responses of tea plant to stress using tissue culture tool (L.S. Samarina et al., 2018; M.V. Gvasaliya et al., 2019). In this article, for the first time, we investigated the role of calcium in plant adaptation to long-term osmotic stress based on earlier published protocols of tea tissue culture (M.V. Gvasaliya, 2013) and osmotic stress induction protocols. We also demonstrated the prospect of studying the role of exogenous inducers in increasing plant tolerance using “drought models”. This work aimed to identify the effect of different concentrations of calcium (Ca2+) in the culture medium on the functional state of tea microshoots grown under mannitol-induced osmotic stress in vitro comparing with control. The changes in morphophysiological state of the leaves, leaves water content, cells membrane permeability, malondialdehyde, proline, and photosynthetic pigments were analyzed. It was found that increased Ca2+content in the nutrient medium (from 440 to 880 mg/l) resulted the slower leaves development and significant decrease of malondialdehyde and cell membranes permeability of tea microshoots (by 50 %, р ≤ 0.05) during the long-term cultivation of tea microshoots in vitro (4 months), indicating inhibition of lipid peroxidation processes. The addition of mannitol (40 g/l) to the culture medium reduced the water content of the shoots (on average by 2 %, р ≤ 0.05), thereby forming light osmotic stress, which led to the accumulation of proline (an increase of 30-40 %, р ≤ 0.05), as well as to the structural and functional rearrangement of the photosynthetic apparatus (a decrease in the amount of photosynthetic pigments by an average of 35-40 %). In addition, a significant decrease of malondialdehyde (by 50-70 %, p ≤ 0.05) and the intensity of electrolyte leakage from leaf tissues (on average by 50 %, p £ 0.05) were observed, indicating a less pronounced oxidative stress in comparison with control (without mannitol). An increase in the Ca2+ concentration in the nutrient medium (from 440 to 880 mg/l) (in the presence of mannitol) did not significantly affect the water content in the leaves and the photosynthetic apparatus (content and ratio of chlorophylls/carotenoids). An insignificant effect of calcium (in the presence of mannitol) manifested itself in a significant decrease in malondialdehyde by 20 μmol/g dry weight. Consequently, the increased concentration of calcium (660-880 mg/l) in the nutrient medium provides an improvement in the functional state of long-term cultivated tea microshoots in vitro (4 months) by reducing the activity of lipid peroxidation in membranes and increasing their stability. The revealed patterns confirm the positive role of calcium ions in the reduction of combined oxidative stress caused by long-term cultivation of plants in vitro in combination with osmotic stress.

Silver nanoparticles from Hpytus suaveolens and their effect on biochemical and physiological parameter in mesquite plants

In this study, a simple and economical procedure to obtain silver nanoparticles using leaf-extract of Hpytus sauveolens (AgNPs) and their effect in chlorophyll, nitrogen balance index and epidermal polyphenols contents, photochemical efficiency and phenylalanine ammonia lyase (PAL) activity in Prosopis juliflora is reported. Synthesized nanoparticles were characterized by ultraviolet (UV) spectroscopy, DLS analyzer, FTIR spectroscopy, Scanning electron microscopy (SEM) and energy dispersive analysis X-ray (EDX). The results showed that AgNPs contained bioactive molecules, which had important function in the reduction of Ag ion. The AgNPs had mean particle size, zeta potential conductivity of 22 nm, 29.50 mv and 1.394 mS/cm, respectively according to DLS analysis. Different doses of AgNPs (100, 75, 50 and 25 ppm) showed positive effects on phenylalanine ammonia lyase (PAL) activity and neutral effect in chlorophyll, nitrogen balance index and epidermal polyphenols contents on plants. Only higher doses (100 ppm) caused negative effects in photochemical efficiency in Prosopis juliflora . Hence future studies are necessary to elucidate the participation of green AgNPs as exogenous inducers of PAL enzyme involved in the phenylpropanoid pathway in Prosopis juliflora in the reduction of stress oxidative in plants. • Synthesis of green silver nanoparticles from native plants using Hpytus suaveolens . • The applications of AgNPs produce changes biochemical in Prosopis juliflora . • Higher doses AgNPs produce negative effects on physiological status. • Green AgNPs increased the PAL activity in plants.

Response of antibiotic resistance genes in constructed wetlands during treatment of livestock wastewater with different exogenous inducers: Antibiotic and antibiotic-resistant bacteria

This work aimed to study the behavior of antibiotic resistance genes (ARGs) in constructed wetlands with different exogenous inducers additions (oxytetracycline and its resistant bacteria) by high-throughput quantitative polymerase chain reaction. Results indicated that constructed wetlands have the potential to reduce ARGs relative abundances in wastewater, and the total ARGs removal efficiency could exceed 60%. ARGs profile in the effluent differed from that in the influent, and that did not directly reflect the export of dominant ARGs in wetland biofilms. Meanwhile, the highest levels of detected numbers and relative abundances of ARGs were 43 and 3.35 × 10−1 for control system and 44 and 6.40 × 10−1 for treatment system, respectively, which meant that ARGs generation in wetlands were inevitable, and antibiotic and antibiotic-resistant bacteria from wastewater could indeed promote ARGs abundance in the system. Compared to the single roles of inducers, their synergistic role had a more significant influence on ARGs relative abundance.

Mini-cuttings of forest and fruit species

Mini-cutting is an important alternative for the production of seedlings of forest and fruit species. The technique is seen as an improvement in cutting, displaying variations for optimizing both the rooting and the quality of clonal seedling. Through this technique it is possible to propagate genotypes with superior characteristics, make better use of the parent plant, and overcome the difficulties of seed propagation. In this context, this review will address the use of vegetative propagation from mini-cuttings of forest and fruit species, highlighting the main advantages of this technique and the use of exogenous inducers and substrates for maximum rooting of seedlings. Despite the potential of minicutting for the propagation of different species, research is still needed so that new knowledge helps to expand its use in agriculture.