Minimizing Viral Transmission in COVID-19 Like Pandemics: Technologies, Challenges, and Opportunities.

Coronavirus (COVID-19) pandemic has incurred huge loss to human lives throughout the world. Scientists, researchers, and doctors are trying their best to develop and distribute the COVID-19 vaccine throughout the world at the earliest. In current circumstances, different tracking systems are utilized to control or stop the spread of the virus till the whole population of the world gets vaccinated. To track and trace patients in COVID-19 like pandemics, various tracking systems based on different technologies are discussed and compared in this paper. These technologies include, cellular, cyber, satellite-based radio navigation and low range wireless technologies. The main aim of this paper is to conduct a comprehensive survey that can overview all such tracking systems, which are used in minimizing the spread of COVID-19 like pandemics. This paper also highlights the shortcoming of each tracking systems and suggests new mechanisms to overcome such limitations. In addition, the authors propose some futuristic approaches to track patients in prospective pandemics, based on artificial intelligence and big data analysis. Potential research directions, challenges, and the introduction of next-generation tracking systems for minimizing the spread of prospective pandemics, are also discussed at the end.

Severity of zinc and iron malnutrition linked to low intake through a staple crop: a case study in east-central Pakistan.

Micronutrients deficiency in soil-plant and human is well-addressed; however, little is known about their spatial distribution, magnitude of deficiency and biological nexus. Zinc deficiency (ZnD) and iron-deficiency anemia (FeD) are two serious nutritional concerns which are negatively affecting human health. Herein, a survey-based case study was conducted in major wheat-based cropping system of east-central Pakistan. Soil and grain samples were collected from 125 field-grown wheat from 25 distinct sites/villages and GPS coordinates were taken for mapping. The collected samples were tags according to the names of 25 sites, i.e., UCs (union councils; an administrative unit). The quantified amount of zinc (Zn) or iron (Fe) in soil-wheat grains was compared with their recommended concentrations (RCZn, RCFe) for human nutrition. Additionally, clinical features of ZnD and FeD were diagnosed among local farmers who used to consume these grains, throughout the year, cultivated on their farm, and quantified their deficiency prevalence (ZnDP, FeDP). Results revealed, the collected 64% (0.54 to 5.25 mg kg-1) soils, and 96% (1.4 to 31 mg kg-1) grain samples are Zn-deficient (RCZn) along with ZnDP recorded among 68% of population. Meanwhile, FeD is quantified in 76% (1.86 to 15 mg kg-1) soil, 72% grain (2.1 to 134 mg kg-1) samples, and FeDP is found among 84% of studied population. A strong and positive correlation is developed in the Zn-or FeDP with their deficiencies in soil and grain by plotting multivariate analysis. In line with spatial distribution pattern, the UCs, namely, 141, 151, 159 and 132 are quantified severe deficient in Zn and Fe, and others are marginal or approaching to deficient level. Our findings rationalize the biological nexus of Zn and Fe, and accordingly, draw attention in the biofortification of staple crop as a win-win approach to combat the rising malnutrition concerns.

Concentration and Localization of Fe and Zn in Wheat Grain as Affected by Its Application to Soil and Foliage.

Nutritional status of people can be improved by enhancing zinc (Zn) and iron (Fe) content in cereals used as staple mainly in poor resource countries. Zinc and Fe were applied through soil and foliage in a study to biofortify wheat grains. Foliar application of both micronutrients increased the growth and grain vigor as compared to soil application and control. Also, foliar application significantly enhanced Zn and Fe concentration in grain pre-dominantly localized in aleurone layer. Exogeneous application of Fe and Zn was found beneficial for plant growth and enhanced Fe and Zn concentrations in grain, however aleurone layer and embryonic region of the grain showed higher accumulations than that in endosperm. Therefore, understanding of physiological and molecular pathways for uptake and localization of Fe and Zn in wheat grains need to be critically examined to improve their concentration in grain to achieve the biofortification targets.

Chromium-Induced Reactive Oxygen Species Accumulation by Altering the Enzymatic Antioxidant System and Associated Cytotoxic, Genotoxic, Ultrastructural, and Photosynthetic Changes in Plants.

Chromium (Cr) is one of the top seven toxic heavy metals, being ranked 21st among the abundantly found metals in the earth's crust. A huge amount of Cr releases from various industries and Cr mines, which is accumulating in the agricultural land, is significantly reducing the crop development, growth, and yield. Chromium mediates phytotoxicity either by direct interaction with different plant parts and metabolic pathways or it generates internal stress by inducing the accumulation of reactive oxygen species (ROS). Thus, the role of Cr-induced ROS in the phytotoxicity is very important. In the current study, we reviewed the most recent publications regarding Cr-induced ROS, Cr-induced alteration in the enzymatic antioxidant system, Cr-induced lipid peroxidation and cell membrane damage, Cr-induced DNA damage and genotoxicity, Cr-induced ultrastructural changes in cell and subcellular level, and Cr-induced alterations in photosynthesis and photosynthetic apparatus. Taken together, we conclude that Cr-induced ROS and the suppression of the enzymatic antioxidant system actually mediate Cr-induced cytotoxic, genotoxic, ultrastructural, and photosynthetic changes in plants.

Use of nano-/micro-magnetite for abatement of cadmium and lead contamination.

Structural variations of a mineral dictate its adsorption capacity which affects the mobility and toxicity of contaminants in natural and engineered systems. Present batch study evaluates the adsorption of lead (Pb) and cadmium (Cd) onto three magnetites having nanometric (M1-30 nm and M2-60 nm) and micrometric particle sizes (M3-1.5 µm). Obtained data revealed that particle size of tested magnetites strongly affected the extent and kinetics of metal adsorption and desorption. Observed order of adsorption efficiency was M1 > M2 > M3 with optimum monolayer adsorption of 408.14, 331.40, 178.47 mg/g (for Pb) and 228.05, 170.86, 83.49 mg/g (for Cd), respectively. Adsorption data were well fitted to the Freundlich (R2 = 0.99), Langmuir (R2 = 0.99) and pseudo-first order models (R2 = 0.98). Electrostatic attraction and surface precipitation interaction via external mass transfer between bulk liquid-solid interfaces were the potential adsorption pathways. Pb showed higher affinity than Cd in multi-metal system. Desorption efficiency was higher in acidic environment (92%) than in distilled water (44%). Moreover, regenerated magnetite samples retained good adsorption capacity for six cycles. As soils are characterized by large variability of iron minerals, these findings have important implications regarding the transport and immobilization of contaminants particularly in the management of contaminated soils.

SPATULA regulates floral transition and photomorphogenesis in a PHYTOCHROME B-dependent manner in Arabidopsis.

Light is the most important exogenous stimulus regulating plant growth and various developmental processes. Phytochromes, especially PHYTOCHROME B (PHYB) mediates the various light-mediated processes in Arabidopsis. SPATULA (SPT) is an important transcription factor, which has been reported previously to participate in temperature-mediated transition from seed dormancy to germination. Here we investigate the function of SPT in the floral transition under long day conditions and photomorphogenesis in Arabidopsis. In this study, spt-2 shows significantly delayed flowering time. But mutation of SPT in the background of phyb-1 rescues the phenotype of spt-2. The flowering time of double mutant of spt-2/phyb-1 is similar with the wild type. These results indicate that SPT promotes the transition from vegetative stage to floral stage and it regulates this transition in a PHYB-dependent manner. With qRT-PCR analysis, it is found that SPT regulates flowering time via FLC, SVP, FT and SOC1. Furthermore, SPT also controls photomorphogenesis. spt-2 displays shortened hypocotyls and increased chlorophylls contents compared with the wild type. These phenotypes are also rescued in the double mutant of spt-2/phyb-1. These results indicate that SPT is also involved in photomorphogenic development in Arabidopsis and SPT regulates photomorphogenesis in a PHYB-dependent manner. Collectively, SPT is not only a temperature responder but it is also an important light regulator during plant growth and development.

Ethylene mediates dichromate-induced inhibition of primary root growth by altering AUX1 expression and auxin accumulation in Arabidopsis thaliana.

The hexavalent form of chromium [Cr(VI)] causes a major reduction in yield and quality of crops worldwide. The root is the first plant organ that interacts with Cr(VI) toxicity, which inhibits primary root elongation, but the underlying mechanisms of this inhibition remain elusive. In this study, we investigate the possibility that Cr(VI) reduces primary root growth of Arabidopsis by modulating the cell cycle-related genes and that ethylene signalling contributes to this process. We show that Cr(VI)-mediated inhibition of primary root elongation was alleviated by the ethylene perception and biosynthesis antagonists silver and cobalt, respectively. Furthermore, the ethylene signalling defective mutants (ein2-1 and etr1-3) were insensitive, whereas the overproducer mutant (eto1-1) was hypersensitive to Cr(VI). We also report that high levels of Cr(VI) significantly induce the distribution and accumulation of auxin in the primary root tips, but this increase was significantly suppressed in seedlings exposed to silver or cobalt. In addition, genetic and physiological investigations show that AUXIN-RESISTANT1 (AUX1) participates in Cr(VI)-induced inhibition of primary root growth. Taken together, our results indicate that ethylene mediates Cr(VI)-induced inhibition of primary root elongation by increasing auxin accumulation and polar transport by stimulating the expression of AUX1.

Involvement of histone acetylation and deacetylation in regulating auxin responses and associated phenotypic changes in plants.

KEY MESSAGE: The most recent outcomes about the transcription factors and transcription complexes mediated auxin signaling pathway by the histone acetylation and deacetylation. The phytohormone auxin, is required to regulate its accumulation spatiotemporally and responses to orchestrate various developmental levels in plants. Histone acetylation and deacetylation modulate auxin biosynthesis, its distribution and accumulation. In the absence of auxin, histone deacetylase represses the expression of auxin-responsive genes. Various transcription factors and transcription complexes facilitate the proper regulation of auxin signaling pathway genes. The primary and lateral root development, promotion of flowering and initiation of seed germination are all regulated by auxin-mediated histone acetylation and deacetylation. These findings conclude the auxin mode of action, which is mediated by histone acetylation and deacetylation, and associated phenotypic responses in plants, along with the underlying mechanism of these modifications.

Biochemical responses and ultrastructural changes in ethylene insensitive mutants of Arabidopsis thialiana subjected to bisphenol A exposure.

Bisphenol A (BPA), an important raw material in plastic industry, has become a serious environmental contaminant due to its wide spread use in different products and increasing release into the environment. BPA is known to cause adverse effects in living organisms including plants. Several studies reported that BPA affects growth and development in plants, mainly through oxidative stress. Plants are known to generally cope with stress mainly through hormonal regulation and adaptation, but little is known about the role of plant hormones in plants under BPA stress. The present study was conducted to investigate the role of ethylene in BPA induced oxidative stress in plants using Arabidopsis thaliana as a test plant. The response of ethylene insensitive mutants of Arabidopsis (ein2-1 and etr1-3) to BPA exposure was studied in comparison to the wild type Arabidopsis (WT). In all three genotypes, exposure to BPA adversely affected cellular structures, stomata and light-harvesting pigments. An increase in reactive oxygen species (ROS) lipid peroxidation and other oxidative stress markers indicated that BPA induced toxicity through oxidative stress. However, the overall results revealed that WT Arabidopsis had more pronounced BPA induced damages while ein2-1 and etr1-3 mutants withstood the BPA induced stress more efficiently. The activity of antioxidant enzymes and expression of antioxidants related genes revealed that the antioxidant defense system in both mutants was more efficiently activated than in WT against BPA induced oxidative stress, which further evidenced the involvement of ethylene in regulating BPA induced oxidative stress. It is concluded that ethylene perception and signaling may be involved in BPA induced oxidative stress responses in plants.

Antimicrobial activity, toxicity and anti-inflammatory potential of methanolic extracts of four ethnomedicinal plant species from Punjab, Pakistan.

BACKGROUND: The plant species Aristolochia indica (AI), Melilotus indicus (MI), Tribulus terrestris (TT) and Cuscuta pedicellata (CP) are widely used in folk medicine in the villages around Chowk Azam, South Punjab, Pakistan. The aim of this study was to evaluate the antioxidant activity, phytochemical composition, and the antibacterial, antifungal, cytotoxic and anti-inflammatory potential of the four medicinal plants listed above. For CP stem, this study represents (to the best of our knowledge) the first time phytochemicals have been identified and the antioxidant and anti-inflammatory potential determined. METHODS: Phytochemicals were analyzed through chemical tests, thin layer chromatography (TLC) and spectrophotometric methods. Antioxidant activities (DPPH and H2O2) were also determined through spectrophotometric methods. Extracts were evaluated for antibacterial potential via the agar well diffusion method against Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia and Acinetobacter baumannii. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined by the microdilution method. Antifungal activities were tested using the agar tube dilution method against three species: Aspergillus fumigatus, Aspergillus flavus and Rhizopus oryzae. The cytotoxic potential of the plant extracts was checked using the brine shrimp assay. In vitro anti-inflammatory activity of the selected plant extracts was evaluated using albumin denaturation, membrane stabilization and proteinase inhibitory assays. RESULTS: Of all the methanolic extracts tested, those from CP (stem) and TTF (T. terrestris fruit) had the highest phenolic, flavonoid and flavonol contents (497±4 mg GAE/g, 385±8 mg QE/g and 139±4 mg QE/g; 426±5 mg GAE/g, 371±8 mg QE/g and 138±6 mg QE/g, respectively) and also exhibited strong antioxidant potential in scavenging DPPH and hydrogen peroxide (IC50 values; 20±1 and 18±0.7 µg/mL; 92±2 and 26±2 µg/mL, respectively). CP, TTF and TTL (T. terrestris leaf) extracts substantially inhibited the growth of the bacteria A. baumannii, S. aureus, and K. pneumonia and also exhibited the highest antifungal potential. The ranking of the plant extracts for cytotoxicity was TTF > TTL > AI > CP > MI, while the ranking for in vitro anti-inflammatory potential at a concentration of 200 µg/mL of the selected plant extracts was CP > TTL, TTF > AI > MI. The lowest IC50 (28 µg/mL) observed in the albumin denaturation assay was for CP. Positive correlations were observed between total phenolics, antioxidants, antibacterial, antifungal and anti-inflammatory potential of the selected plant extracts, indicating a significant contribution of phenolic compounds in the plant extracts to these activities. CONCLUSIONS: This study revealed the strong antimicrobial, antioxidant, cytotoxic and anti-inflammatory potential of the plant species CP and TT used in folk medicine.

Role of reactive nitrogen species in changing climate and future concerns of environmental sustainability.

The nitrogen (N) cycle is an intricate biogeochemical process that encompasses the conversion of several chemical forms of N. Given its role in food production, the need for N for life on Earth is obvious. However, the release of reactive nitrogen (Nr) species throughout different biogeochemical processes contributes to atmospheric pollution. Several human activities generate many species, including ammonia, nitrous oxide (N2O), nitric oxide, and nitrate. The primary reasons for this change are the use of nitrogen-based fertilizers, industrial activities, and the burning of fossil fuels. N2O poses a significant threat to environmental sustainability on our planet, with its global warming potential approximately 298 times greater than that of CO2. It has direct or indirect impacts on the environment, agroecosystem, and human life on earth. Solar, hydroelectric, geothermal, and wind turbines must be used to reduce Nr emissions. In addition, enterprises should install catalytic converters to minimize nitrogen gas emissions. To reduce Nr emissions, strategic interventions like fertilizer balancing are needed. This work will serve as a comprehensive guide for researchers, academics, and policymakers. Additionally, it will also assist social workers in emphasizing the Nr issue to the public in order to raise awareness within worldwide society.

Root system architecture associated zinc variability in wheat (Triticum aestivum L.).

Root system architecture (RSA) plays a fundamental role in nutrient uptake, including zinc (Zn). Wheat grains are inheritably low in Zn. As Zn is an essential nutrient for plants, improving its uptake will not only improve their growth and yield but also the nutritional quality of staple grains. A rhizobox study followed by a pot study was conducted to evaluate Zn variability with respect to RSA and its impact on grain Zn concentration. The grain Zn content of one hundred wheat varieties was determined and grown in rhizoboxes with differential Zn (no Zn and 0.05 mg L-1 ZnSO4). Seedlings were harvested 12 days after sowing, and root images were taken and analyzed by SmartRoot software. Using principal component analysis, twelve varieties were screened out based on vigorous and weaker RSA with high and low grain Zn content. The screened varieties were grown in pots with (11 mg ZnSO4 kg-1 soil) and without Zn application to the soil. Zinc translocation, localization, and agronomic parameters were recorded after harvesting at maturity. In the rhizobox experiment, 4% and 8% varieties showed higher grain Zn content with vigorous and weaker RSA, respectively, while 45% and 43% varieties had lower grain Zn content with vigorous and weaker RSA. However, the pot experiment revealed that varieties with vigorous root system led to higher grain yield, though the grain Zn concentration were variable, while all varieties with weaker root system had lower yield as well as grain Zn concentration. Zincol-16 revealed the highest Zn concentration (28.07 mg kg-1) and grain weight (47.9 g). Comparatively higher level of Zn was localized in the aleurone layer than in the embryonic region and endosperm. It is concluded that genetic variability exists among wheat varieties for RSA and grain Zn content, with a significant correlation. Therefore, RSA attributes are promising targets for the Zn biofortification breeding program. However, Zn localization in endosperm needs to be further investigated to achieve the goal of reducing Zn malnutrition.

Mediation of gaseous emissions and improving plant productivity by DCD and DMPP nitrification inhibitors: Meta-analysis of last three decades.

Nitrification inhibitors (NIs), especially dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP), have been extensively investigated to mitigate nitrogen (N) losses from the soil and thus improve crop productivity by enhancing N use efficiency. However, to provide crop and soil-specific guidelines about using these NIs, a quantitative assessment of their efficacy in mitigating gaseous emissions, worth for nitrate leaching, and improving crop productivity under different crops and soils is yet required. Therefore, based upon 146 peer-reviewed research studies, we conducted a meta-analysis to quantify the effect of DCD and DMPP on gaseous emissions, nitrate leaching, soil inorganic N, and crop productivity under different variates. The efficacy of the NIs in reducing the emissions of CO2, CH4, NO, and N2O highly depends on the crop, soil, and experiment types. The comparative efficacy of DCD in reducing N2O emission was higher than the DMPP under maize, grasses, and fallow soils in both organic and chemical fertilizer amended soils. The use of DCD was linked to increased NH3 emission in vegetables, rice, and grasses. Depending upon the crop, soil, and fertilizer type, both the NIs decreased nitrate leaching from soils; however, DMPP was more effective. Nevertheless, the effect of DCD on crop productivity indicators, including N uptake, N use efficiency, and biomass/yield was higher than DMPP due to certain factors. Moreover, among soils, crops, and fertilizer types, the response by plant productivity indicators to the application of NIs ranged between 35 and 43%. Overall, the finding of this meta-analysis strongly suggests the use of DCD and DMPP while considering the crop, fertilizer, and soil types.

Nanobiotechnology in crop stress management: an overview of novel applications.

Agricultural crops are subject to a variety of biotic and abiotic stresses that adversely affect growth and reduce the yield of crop plantss. Traditional crop stress management approaches are not capable of fulfilling the food demand of the human population which is projected to reach 10 billion by 2050. Nanobiotechnology is the application of nanotechnology in biological fields and has emerged as a sustainable approach to enhancing agricultural productivity by alleviating various plant stresses. This article reviews innovations in nanobiotechnology and its role in promoting plant growth and enhancing plant resistance/tolerance against biotic and abiotic stresses and the underlying mechanisms. Nanoparticles, synthesized through various approaches (physical, chemical and biological), induce plant resistance against these stresses by strengthening the physical barriers, improving plant photosynthesis and activating plant defense mechanisms. The nanoparticles can also upregulate the expression of stress-related genes by increasing anti-stress compounds and activating the expression of defense-related genes. The unique physico-chemical characteristics of nanoparticles enhance biochemical activity and effectiveness to cause diverse impacts on plants. Molecular mechanisms of nanobiotechnology-induced tolerance to abiotic and biotic stresses have also been highlighted. Further research is needed on efficient synthesis methods, optimization of nanoparticle dosages, application techniques and integration with other technologies, and a better understanding of their fate in agricultural systems.

Recent trends in the use of fly ash for the adsorption of pollutants in contaminated wastewater and soils: Effects on soil quality and plant growth.

Fly ash is one of the largest types of industrial wastes produced during the combustion of coal for energy generation. Finding efficient and sustainable solutions for its reuse has been the subject of substantial research worldwide. Here, we review the recent research data related to (i) the use of fly ash as a low-cost adsorbent for pollutants in wastewater and soils and (ii) its implications in soil-plant system. Fly ash showed prominent adsorption capacity for pollutants in water especially when it was activated or applied in composites. In addition to direct pollutant binding in soils, fly ash can enhance the soil pH indirectly increasing metals' immobilization reducing their plant uptake. Its non-selective adsorptive nature may lead to the co-adsorption of nutrients with pollutants which merits to be considered. Owing to its considerable nutrient contents, fly ash can also improve soil fertility and plant growth. The effects of fly ash on soil physico-chemical properties, microbial population and plant growth are critically evaluated. Fly ash can also contain potentially toxic contaminants (toxic metals, hydrocarbons, etc.) which could have harmful impacts on soil health and plant growth. Identifying the levels of inherent pollutants in fly ash is crucial to evaluate its suitability as a soil amendment. Negative effects of fly ash can also be addressed by using co-amendments, biological agents, and most importantly by an adequate calibration (dose and type) of fly ash based on site-specific conditions. Research directions are identified to promote the research regarding its use in wastewater treatment and agriculture.

Mineral biofortification of vegetables through soil-applied poultry mortality compost.

Intensive agricultural practices lower soil fertility, particularly micronutrients which are rarely applied to soils as chemical fertilizers. Micronutrient deficiency in soils results in inferior product quality and micronutrient malnutrition in humans. Application of compost to soil may improve crop yields and quality by enhancing macro- and micronutrients availability, enhancing soil microbial population, and improving soil physicochemical properties. Poultry mortality compost (PMC) was prepared by decomposing dead poultry birds with poultry litter in an aerated bin through indigenous microbial populations. The prepared PMC was used as an amendment in three field experiments during 2017-18 and 2018-19 to investigate the effect on yield and nutritional quality of potato, carrot, and radish. In these field trials, two compost levels, i.e., 1250 kg ha-1 (PMC1) and 1850 kg ha-1 (PMC2) were compared with the control (no compost application). The results revealed a 10-25% increase in root or tuber yield at PMC2 compared to that in the control. A substantial increase in Zn, Fe, and Mn concentrations in vegetable root/tubers was also observed. Organic matter content and microbial biomass were improved in the soil with PMC application leading to better soil health and better nutrient availability. These studies led us to conclude that the application of PMC not only enhances the vegetable yield but also biofortifies vegetables with micronutrients such as Zn, Fe, and Mn extending agricultural sustainability and eliminating micronutrient malnutrition in humans.

Enriching Urea with Nitrogen Inhibitors Improves Growth, N Uptake and Seed Yield in Quinoa (Chenopodium quinoa Willd) Affecting Photochemical Efficiency and Nitrate Reductase Activity.

Quinoa is a climate resilience potential crop for food security due to high nutritive value. However, crop variable response to nitrogen (N) use efficiency may lead to affect grain quality and yield. This study compared the performance of contrasting quinoa genotypes (UAF Q-7, EMS-line and JQH1) to fertilizer urea enriched with urease and nitrification inhibitors (NIs; 1% (w/w) thiourea + boric acid + sodium thiosulphate), ordinary urea and with no N as control. Application of NIs-enriched urea improved plant growth, N uptake and chlorophyll values in quinoa genotype UAF-Q7 and JHQ1, however, highest nitrate reductase (NR) activity was observed in EMS-line. Quinoa plants supplied with NIs-enriched urea also completed true and multiple leaf stage, bud formation, flowering, and maturity stages earlier than ordinary urea and control, nevertheless, all quinoa genotypes reached true and multiple leaf stage, flowering and maturity stages at same time. Among photosynthetic efficiency traits, application of NIs-enriched urea expressed highest photosynthetic active radiations (PAR), electron transport rate (ETR), current fluorescence (Ft) and reduced quantum yield (Y) in EMS line. Nitrogen treatments had no significant difference for panicle length, however, among genotypes, UAF-Q7 showed highest length of panicle followed by others. Among yield attributes, NIs-enriched urea expressed maximum 1000-seed weight and seed yield per plant in JQH-1 hybrid and EMS-line. Likely, an increase in quinoa grain protein contents was observed in JQH-1 hybrid for NIs-enriched urea. In conclusion, NIs-enriched urea with urease and nitrification inhibitors simultaneously can be used to improve the N uptake, seed yield and grain protein contents in quinoa, however, better crop response was attributed to enhanced plant growth and photosynthetic efficiency.

Tyrosine-phosphorylated Ehrlichia chaffeensis and Ehrlichia canis tandem repeat orthologs contain a major continuous cross-reactive antibody epitope in lysine-rich repeats.

A small subset of major immunoreactive proteins have been identified in Ehrlichia chaffeensis and Ehrlichia canis, including three molecularly and immunologically characterized pairs of immunoreactive tandem repeat protein (TRP) orthologs with major continuous species-specific epitopes within acidic tandem repeats (TR) that stimulate strong antibody responses during infection. In this study, we identified a fourth major immunoreactive TR-containing ortholog pair and defined a major cross-reactive epitope in homologous nonidentical 24-amino-acid lysine-rich TRs. Antibodies from patients and dogs with ehrlichiosis reacted strongly with recombinant TR regions, and epitopes were mapped to the N-terminal TR region (18 amino acids) in E. chaffeensis and the complete TR (24 amino acids) in E. canis. Two less-dominant epitopes were mapped to adjacent glutamate/aspartate-rich and aspartate/tyrosine-rich regions in the acidic C terminus of E. canis TRP95 but not in E. chaffeensis TRP75. Major immunoreactive proteins in E. chaffeensis (75-kDa) and E. canis (95-kD) whole-cell lysates and supernatants were identified with TR-specific antibodies. Consistent with other ehrlichial TRPs, the TRPs identified in ehrlichial whole-cell lysates and the recombinant proteins migrated abnormally slow electrophoretically a characteristic that was demonstrated with the positively charged TR and negatively charged C-terminal domains. E. chaffeensis TRP75 and E. canis TRP95 were immunoprecipitated with anti-pTyr antibody, demonstrating that they are tyrosine phosphorylated during infection of the host cell.