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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]