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The Pseudomonas syringae type III secretion system (TTSS) translocates effector proteins into plant cells. Several P. syringae effectors require accessory proteins called type III chaperones (TTCs) to be secreted via the TTSS. We characterized the hopO1-1, hopS1, and hopS2 operons in P. syringae pv. tomato DC3000; these operons encode three homologous TTCs, ShcO1, ShcS1, and ShcS2. ShcO1, ShcS1, and ShcS2 facilitated the type III secretion and/or translocation of their cognate effectors HopO1-1, HopS1, and HopS2, respectively. ShcO1 and HopO1-1 interacted with each other in yeast two-hybrid and coimmunoprecipitation assays. Interestingly, ShcS1 and ShcS2 were capable of substituting for ShcO1 in facilitating HopO1-1 secretion and translocation and each TTC was able to bind the other's cognate effectors in yeast two-hybrid assays. Moreover, ShcO1, ShcS1, and ShcS2 all bound to the middle-third region of HopO1-1. The HopS2 effector possessed atypical P. syringae TTSS N-terminal characteristics and was translocated in low amounts. A site-directed HopS2 mutation that introduced a common N-terminal characteristic from other P. syringae type III secreted substrates increased HopS2 translocation, supporting the idea that this characteristic functions as a secretion signal. Additionally, hopO1-2 and hopT1-2 were shown to encode effectors secreted via the DC3000 TTSS. Finally, a DC3000 hopO1-1 operon deletion mutant produced disease symptoms similar to those seen with wild-type DC3000 but was reduced in its ability to multiply in Arabidopsis thaliana. The existence of TTCs that can bind to dissimilar effectors and that can substitute for each other in effector secretion provides insights into the nature of how TTCs function.

Summary: Triterpenes are thirty‐carbon compounds derived from the universal five‐carbon prenyl precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Normally, triterpenes are synthesized via the mevalonate (MVA) pathway operating in the cytoplasm of eukaryotes where DMAPP is condensed with two IPPs to yield farnesyl diphosphate (FPP), catalyzed by FPP synthase (FPS). Squalene synthase (SQS) condenses two molecules of FPP to generate the symmetrical product squalene, the first committed precursor to sterols and most other triterpenes. In the green algae Botryococcus braunii, two FPP molecules can also be condensed in an asymmetric manner yielding the more highly branched triterpene, botryococcene. Botryococcene is an attractive molecule because of its potential as a biofuel and petrochemical feedstock. Because B. braunii, the only native host for botryococcene biosynthesis, is difficult to grow, there have been efforts to move botryococcene biosynthesis into organisms more amenable to large‐scale production. Here, we report the genetic engineering of the model monocot, Brachypodium distachyon, for botryococcene biosynthesis and accumulation. A subcellular targeting strategy was used, directing the enzymes (botryococcene synthase [BS] and FPS) to either the cytosol or the plastid. High titres of botryococcene (>1 mg/g FW in T0 mature plants) were obtained using the cytosolic‐targeting strategy. Plastid‐targeted BS + FPS lines accumulated botryococcene (albeit in lesser amounts than the cytosolic BS + FPS lines), but they showed a detrimental phenotype dependent on plastid‐targeted FPS, and could not proliferate and survive to set seed under phototrophic conditions. These results highlight intriguing differences in isoprenoid metabolism between dicots and monocots. [ABSTRACT FROM AUTHOR]

By using solar energy as the power source, aligned and clean reclaimed carbon fibers (RCFs) were successfully recovered from carbon fiber-reinforced polymer (CFRP). Furthermore, α-MnO 2 nanowires were grown on the RCF surface through a one-step hydrothermal process, and thus MnO 2 /RCF composite was successfully prepared. Both the RCF and MnO 2 /RCF can be directly utilized as supercapacitor electrode, and the electrochemical performance of the electrode materials were evaluated by utilizing cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a three-electrode cell. RCF electrode exhibited a favorable performance with a prolonged potential window (−1.6–0 V) in a 2 mol L −1 of aqueous KOH solution, while the MnO 2 /RCF electrode prepared at 150 °C showed a superior electrochemical performance in a 1 mol L −1 of aqueous Na 2 SO 4 solution: a specific capacitance of 228.8 F g −1 at 1 A g −1 and high cycling stability (about 91.2% capacitance retention after 3000 cycles). A MnO 2 /RCF-based asymmetric supercapacitor was assembled, which exhibited excellent performances with a voltage window of 2.0 V, a high energy density of 22.9 Wh kg −1 and a remarkable cycling stability (89% capacitance retained after 1000 cycles at 2.25 A g −1 ). [ABSTRACT FROM AUTHOR]

Of central importance in adapting plants of tropical origin to temperate cultivation has been selection of daylengthneutral genotypes that flower early in the temperate summer and take full advantage of its long days. A cross between tropical and temperate sorghums [Sorghum propinquum (Kunth) Hitchc. xS. bicolor (L.) Moench], revealed a quantitative trait locus (QTL), FlrAvgD1, accounting for 85.7% of variation in flowering time under long days. Fine-scale genetic mapping placed FlrAvgD1 on chromosome 6 within the physically largest centiMorgan in the genome. Forward genetic data from “converted" sorghums validated the QTL. Association genetic evidence from a diversity panel delineated the QTL to a 10-kb interval containing only one annotated gene, Sb06g012260, that was shown by reverse genetics to complement a recessive allele. Sb06g012260 (SbFT12) contains a phosphatidylethanolamine-binding (PEBP) protein domain characteristic of members of the “FT" family of flowering genes acting as a floral suppressor. Sb06g012260 appears to have evolved ~40Ma in a panicoid ancestor after divergence from oryzoid and pooid lineages. A speciesspecific Sb06g012260 mutation may have contributed to spread to temperate regions by S. halepense (“Johnsongrass"), one of the world's most widespread invasives. Alternative alleles for another family member, Sb02g029725 (SbFT6), mapping near another flowering QTL, also showed highly significant association with photoperiod response index (P¼1.53x10 6). The evolution of Sb06g012260 adds to evidence that single gene duplicates play large roles in important environmental adaptations. Increased knowledge of Sb06g012260 opens new doors to improvement of sorghum and other grain and cellulosic biomass crops. [ABSTRACT FROM AUTHOR]

Clean, undamaged carbon fibers were easily separated from thermoset epoxy-based carbon fiber reinforced polymers through a two-step solvothermal method by using propanol or benzyl alcohol as solvents. The recovered carbon fibers were characterized by thermal gravity analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical tensile strength tests together with the digital photos. Results show that solvothermal temperature and duration, as well as pretreatment in dichloromethane play important roles in recovering carbon fiber. In addition, the tensile strength of the recovered carbon fibers remains approximately 94.5–98% of virgin carbon fibers. [ABSTRACT FROM AUTHOR]

Sorghum prolamins, termed kafirins, are categorized into subgroups α, β, and γ. The kafirins are co-translationally translocated to the endoplasmic reticulum (ER) where they are assembled into discrete protein bodies that tend to be poorly digestible with low functionality in food and feed applications. As a means to address the issues surrounding functionality and digestibility in sorghum, we employed a biotechnology approach that is designed to alter protein body structure, with the concomitant synthesis of a co-protein in the endosperm fraction of the grain. Wherein perturbation of protein body architecture may provide a route to impact digestibility by reducing disulphide bonds about the periphery of the body, while synthesis of a co-protein, with known functionality attributes, theoretically could impact structure of the protein body through direct association and/or augment end-use applications of sorghum flour by stabilizing ß-sheet formation of the kafirins in sorghum dough preparations. This in turn may improve viscoelasticity of sorghum dough. To this end, we report here on the molecular and phenotypic characterizations of transgenic sorghum events that are down-regulated in γ- and the 29-kDa α-kafirins and the expression of a wheat Dy10/Dx 5 hybrid high-molecular weight glutenin protein. The results demonstrate that down-regulation of γ-kafirin alone does not alter protein body formation or impacts protein digestibility of cooked flour samples. However, reduction in accumulation of a predicted 29-kDa α-kafirin alters the morphology of protein body and enhances protein digestibility in both raw and cooked samples. [ABSTRACT FROM AUTHOR]

Aligned reclaimed carbon fiber (RCF) was reused as a conductive support to load hierarchical molybdenum disulfide (MoS 2 ) spheres and thus MoS 2 /RCF composite was constructed. The synthesis of MoS 2 and its loading were simultaneously completed during a facile hydrothermal process. This MoS 2 /RCF was directly utilized as the negative electrode for supercapacitor without any further process, which exhibited superior electrochemical performance: A specific capacitance of 225 F g −1 at 0.5 A g −1 . Furthermore, an asymmetric supercapacitor (ASC) was assembled by coupling this MoS 2 /RCF electrode (−) with MnO 2 /RCF electrode (+), which delivered an energy density of 22.5 W h kg −1 at a power density of 703 W kg −1 over a wide potential range of 1.7 V. This RCF may be a promising conductive support candidate for those electrodes in the energy storage devices. [ABSTRACT FROM AUTHOR]

Enhancing crop water use efficiency (WUE) is a key target trait for climatic resilience and expanding cultivation on marginal lands. Engineering lower stomatal density to reduce stomatal conductance (gs) has improved WUE in multiple C3 crop species. However, reducing gs in C3 species often reduces photosynthetic carbon gain. A different response is expected in C4 plants because they possess specialized anatomy and biochemistry which concentrates CO2 at the site of fixation. This modifies the photosynthesis (AN) relationship with intracellular CO2 concentration (ci) so that photosynthesis is CO2-saturated and reductions in gs are unlikely to limit AN. To test this hypothesis, genetic strategies were investigated to reduce stomatal density in the C4 crop sorghum. Constitutive expression of a synthetic epidermal patterning factor (EPF) transgenic allele in sorghum, led to reduced stomatal densities, reduced gs, reduced plant water use and avoidance of stress during a period of water deprivation. In addition, moderate reduction in stomatal density did not increase stomatal limitation to AN. However, these positive outcomes were associated with negative pleiotropic effects on reproductive development and photosynthetic capacity. Avoiding pleiotropy by targeting expression of the transgene to specific tissues could provide a pathway to improved agronomic outcomes., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

The drought-resilient crop sorghum ( Sorghum bicolor [L.] Moench) is grown worldwide for multiple uses, including forage or potential lignocellulosic bioenergy feedstock. A major impediment to biomass yield and quality are the pathogens Fusarium thapsinum and Macrophomina phaseolina , which cause Fusarium stalk rot and charcoal rot, respectively. These fungi are more virulent with abiotic stresses such as drought. Monolignol biosynthesis plays a critical role in plant defense. The genes Brown midrib ( Bmr ) 6 , Bmr12 , and Bmr2 encode the monolignol biosynthesis enzymes cinnamyl alcohol dehydrogenase, caffeic acid O -methyltransferase, and 4-coumarate:CoA ligase, respectively. Plant stalks from lines overexpressing these genes and containing bmr mutations were screened for pathogen responses with controlled adequate or deficit watering. Additionally, near-isogenic bmr12 and wild-type lines in five backgrounds were screened for response to F. thapsinum with adequate and deficit watering. All mutant and overexpression lines were no more susceptible than corresponding wild-type under both watering conditions. The bmr2 and bmr12 lines, near-isogenic to wild-type, had significantly shorter mean lesion lengths (were more resistant) than RTx430 wild-type when inoculated with F. thapsinum under water deficit. Additionally, bmr2 plants grown under water deficit had significantly smaller mean lesions when inoculated with M. phaseolina than under adequate-water conditions. When well-watered, bmr12 in cultivar Wheatland and one of two Bmr2 overexpression lines in RTx430 had shorter mean lesion lengths than corresponding wild-type lines. This research demonstrates that modifying monolignol biosynthesis for increased usability may not impair plant defenses but can even enhance resistance to stalk pathogens under drought conditions., Competing Interests: The author(s) declare no conflict of interest.

Nitrogen is essential for plant growth and development. Improving the ability of plants to acquire and assimilate nitrogen more efficiently is a key agronomic parameter that will augment sustainability in agriculture. A transcription factor approach was pursued to address improvement of nitrogen use efficiency in two major commodity crops. To this end, the Zea mays Dof1 ( ZmDof1 ) transcription factor was expressed in both wheat ( Triticum aestivum ) and sorghum ( Sorghum bicolor ) either constitutively, UBI4 promoter from sugarcane, or in a tissue specific fashion via the maize rbcS1 promoter. The primary transcription activation target of ZmDof1 , phospho enol pyruvate carboxylase (PEPC), is observed in transgenic wheat events. Expression ZmDof1 under control of the rbcs1 promoter translates to increase in biomass and yield components in wheat. However, constitutive expression of ZmDof1 led to the down-regulation of genes involved in photosynthesis and the functional apparatus of chloroplasts, and an outcome that negatively impacts photosynthesis, height, and biomass in wheat. Similar patterns were also observed in sorghum transgenic events harboring the constitutive expression cassette of ZmDof1 . These results indicate that transcription factor strategies to boost agronomic phenotypic outcomes in crops need to consider expression patterns of the genetic elements to be introduced.

Agrobacterium-mediated transformation of sorghum (Sorghum bicolor L. Moench) targeting immature embryo explants is a route to introduce transgenic alleles into the crop. The protocol requires maintenance of quality stock plants under greenhouse conditions for a constant supply of immature embryo explants. This is typically carried out by a regular sowing of seeds, minimal use of pesticides, and monitoring of plants to document pollen dispersal and bagging of heads. The time frame from explant inoculation to establishment of a primary transgenic event in the greenhouse typically ranges from 4 to 6 months. Seed set in the primary transformants is comparable to greenhouse-grown stock plants, with the majority of the transgenic alleles being inherited as a single functional locus.

A sensitive and selective liquid chromatographic-mass spectrometric (LC-MS) method for the determination of amlodipine (CAS 88150-42-9) in human plasma has been developed. Sample preparation was based on liquid-liquid extraction using NaOH and cyclohexane. Analytical determination was carried out on a C18 column interfaced with a single quadrupole mass spectrometer. Positive electrospray ionization was employed as the ionization source. The mobile phase was 10 mmol/L ammonium acetate solution-methanol (30:70, v/v) at the flow rate of 0.2 mL/min. The method was linear in the concentration range of 0.2-20 ng/mL. The lower limit of quantification was 0.2 ng/mL. Amlodipine was sensitive to UV light. The method was validated in terms of accuracy, precision, absolute recovery, and stability. The intra- and interday relative standard deviation across three validation runs over the entire concentration range was less than 8.17%. The accuracy determined at three concentrations (0.4, 2.0 and 10 ng/mL for amlodipine maleate) was within +/- 3.17% in terms of relative error. The method herein described was successfully applied for the evaluation of pharmacokinetic profiles of amlodipine maleate tablets in 20 healthy volunteers. The results showed that AUC, Tmax, Cmax and T 1/2 between the test and reference formulation have no significant difference (P > 0.05). The relative bioavailability was 103.7 +/- 12.3%.