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Seeds of the desert shrub, jojoba ( Simmondsia chinensis ), are an abundant, renewable source of liquid wax esters, which are valued additives in cosmetic products and industrial lubricants. Jojoba is relegated to its own taxonomic family, and there is little genetic information available to elucidate its phylogeny. Here, we report the high-quality, 887-Mb genome of jojoba assembled into 26 chromosomes with 23,490 protein-coding genes. The jojoba genome has only the whole-genome triplication (γ) shared among eudicots and no recent duplications. These genomic resources coupled with extensive transcriptome, proteome, and lipidome data helped to define heterogeneous pathways and machinery for lipid synthesis and storage, provided missing evolutionary history information for this taxonomically segregated dioecious plant species, and will support efforts to improve the agronomic properties of jojoba., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

This study focuses on the chemical route sourcing of illicitly produced Δ9-Tetrahydrocannabinol (Δ9-THC) via the acid-catalyzed cannabidiol isomerization reaction. Each of the acid-catalyzed reactions used acids that are readily available for the general population such as battery acid, muriatic acid, and vinegar. After the acid-catalyzed isomerization was complete, an analysis using Liquid Chromatography-coupled-Mass Spectrometry (LC-MS)-coupled-ion mobility to confirm all synthetic impurities in the sample was conducted. The conducted chemical route sourcing allows law enforcement to be able to determine how CBD was converted to psychoactive cannabinoids. Specifically, 10-methoxy-THC, 11-hydroxy-THC, 11,5″-dihydroxy-Δ9-THC, and 5″-hydroxy-CBD were able to be used as indicators in the determination of the chemical route sourcing. Additionally, the ion mobility allowed for a rapid secondary separation of the psychoactive cannabinoids without the need for the long LC/MS analysis time., (Copyright © 2020. Published by Elsevier B.V.)

Zebrafish thrombocytes are similar to mammalian platelets. Mammals have young platelets (also called reticulated platelets) and mature platelets. Likewise, zebrafish have 2 populations of thrombocytes; one is DiI-C 18 (DiI) + (DP), and the other is DiI - (DN). However, the mechanism of selective thrombocyte labeling by DiI is unknown. Furthermore, there is no transgenic zebrafish line where DP and DN thrombocytes are differentially labeled with fluorescent proteins. In this study, we found that Glo fish, in which the myosin light chain 2 promoter drives the rfp gene, have a population of thrombocytes that are red fluorescent protein (RFP) labeled. We also generated transgenic GloFli fish in which DP and DN thrombocytes are labeled with RFP and green fluorescent protein (GFP), respectively. Single-cell lipid analysis showed a twofold increase in phosphatidylethanolamine (PE) and a twofold decrease in phosphatidylcholine (PC) in RFP + thrombocytes compared with GFP + thrombocytes, suggesting that lipid composition may be important for DiI differential labeling. Therefore, we tested liposomes prepared with different ratios of PC and PE and observed that liposomes prepared with higher amounts of PE favor DiI labeling, whereas the PC concentration had a modest effect. In liposomes prepared using only PE or PC, increased concentrations of PE resulted in increased DiI binding. These results suggest that because RFP + thrombocytes have higher PE concentrations, DiI may bind to them efficiently, thus explaining the selective labeling of thrombocytes by DiI. This work also provides GloFli fish that should be useful in understanding the mechanism of thrombocyte maturation., (© 2019 by The American Society of Hematology.)

Impurity profiling has been used as a useful tool for analyzing nearly every drug class currently known on the illicit market. Impurities present within seized samples have the potential to determine source of origin, route of synthesis used, as well as provide a useful clue into the potential reaction mechanisms that are present for each synthetic procedure. Perhaps the most well studied of these impurity profiles exists for methamphetamine, including information to more than one route of synthesis. Within the present study, a complete synthesis of methamphetamine was performed, including a reductive amination of phenylpropanone (P2P) using methylamine hydrochloride and sodium triacetoxyborohydride (STAB) rather than the conventional aluminum mercury amalgam commonly found in the literature. During the analysis of the final product from this reaction, a major impurity within the reaction, bis(1-phenylpropan-2-yl)amine (m/z 253), was detected by GC-MS as well as direct-infusion ESI-MS. This impurity has been previously reported as a Leuckart route-specific impurity. Its detection within the reductive amination of P2P points towards the use of impure methylamine hydrochloride containing some traces of acid, and provides further insight into the reductive amination of P2P. In both the Leuckart reaction and this reductive amination via STAB, the presence of acid and ammonia leads to this impurity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Abiotic stresses such as drought, heat or salinity are a major cause of yield loss worldwide. Recent studies revealed that the acclimation of plants to a combination of different environmental stresses is unique and cannot be directly deduced from studying the response of plants to each of the different stresses applied individually. Here we report on the response of Arabidopsis thaliana to a combination of salt and heat stress using transcriptome analysis, physiological measurements and mutants deficient in abscisic acid, salicylic acid, jasmonic acid or ethylene signaling. Arabidopsis plants were found to be more susceptible to a combination of salt and heat stress compared to each of the different stresses applied individually. The stress combination resulted in a higher ratio of Na+/K+ in leaves and caused the enhanced expression of 699 transcripts unique to the stress combination. Interestingly, many of the transcripts that specifically accumulated in plants in response to the salt and heat stress combination were associated with the plant hormone abscisic acid. In accordance with this finding, mutants deficient in abscisic acid metabolism and signaling were found to be more susceptible to a combination of salt and heat stress than wild type plants. Our study highlights the important role abscisic acid plays in the acclimation of plants to a combination of two different abiotic stresses.

Titanium dioxide nanoparticles (TiO2 NP) are one of the most abundantly utilized nanoparticles in the world. Studies have demonstrated the ability of the anatase crystal of TiO2 NP to produce reactive oxygen species (ROS) in the presence of ultraviolet radiation (UVR), a co-exposure likely to occur in aquatic ecosystems. The goal of this study was to examine the photo-induced toxicity of anatase TiO2 NP under natural sunlight to Daphnia magna. D. magna were exposed to a range of UVR intensities and anatase TiO2 concentrations in an outdoor exposure system using the sun as the source of UVR. Different UVR intensities were achieved using UVR opaque and transparent plastics. AnataseTiO2-NP demonstrated the reciprocal relationship seen in other phototoxic compounds such as polycyclic aromatic hydrocarbons (PAHs) at higher UVR treatments. The calculated 8h LC50 of anatase TiO2 NP was 139 ppb under full intensity ambient natural sunlight, 778 ppb under 50% natural sunlight, and >500 ppm under 10% natural sunlight. Mortality was also compared between animals allowed to accumulate a body burden of anatase TiO2 for 1h and organisms whose first exposure to anatase TiO2 aqueous suspensions occurred under UVR. A significantly greater toxic effect was observed in aqueous, low body burden suspensions than that of TiO2 1h body burdens, which is dissimilar from the model presented in PAHs. Anatase TiO2 presents a unique photo-induced toxic model that is different than that of established phototoxic compounds., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A method for the extraction and analysis of ink samples was developed using microscopy with direct analyte probe nanoextraction coupled to nanospray ionization mass spectrometry (DAPNe-NSI-MS) for localized chemical analysis of document inks. Nanomanipulation can be effectively coupled to nanospray ionization mass spectrometry providing picomolar sensitivity, and the capability to analyze ultra-trace amounts of material and reduce the required sample volume to as low as 300 nL. This new and innovative technique does not leave destructive footprints on the surface of a document. To demonstrate the breadth of this technique, analysis of inks from various eras were tested, iron gall ink and modern inks, as well as the capability to detect the oxidative products of polyethylene glycol (PEG), a common binding agent. The experimental results showed that DAPNe-NSI-MS was able to chelate iron(II) and manganese(II) ions of iron gall ink and organic components of modern and carbon-based inks. Regardless of whether the ink composition is modern or ancient, organic or inorganic, this new instrumental approach is able to identify and characterize the ingredients by modifying the extraction solvent, illustrating the potential diversity of the DAPNe technique., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Direct analysis in real time mass spectrometry (DART-MS) has proven to be a useful forensic tool for the trace analysis of energetic materials. While other techniques for detecting trace amounts of explosives involve extraction, derivatization, solvent exchange, or sample clean-up, DART-MS requires none of these. Typical DART-MS analyses directly from a solid sample or from a swab have been quite successful; however, these methods may not always be an optimal sampling technique in a forensic setting. For example, if the sample were only located in an area which included a latent fingerprint of interest, direct DART-MS analysis or the use of a swab would almost certainly destroy the print. To avoid ruining such potentially invaluable evidence, another method has been developed which will leave the fingerprint virtually untouched. Direct analyte-probed nanoextraction coupled to nanospray ionization-mass spectrometry (DAPNe-NSI-MS) has demonstrated excellent sensitivity and repeatability in forensic analyses of trace amounts of illicit drugs from various types of surfaces. This technique employs a nanomanipulator in conjunction with bright-field microscopy to extract single particles from a surface of interest and has provided a limit of detection of 300 attograms for caffeine. Combining DAPNe with DART-MS provides another level of flexibility in forensic analysis, and has proven to be a sufficient detection method for trinitrotoluene (TNT), RDX, and 1-methylaminoanthraquinone (MAAQ)., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

The method of residue extraction through electrostatic lifting provides a distinctive mode of performing ultra-trace analysis. These lifts provide a medium for analyte extraction via nanomanipulation-coupled to nanospray ionization-mass spectrometry (NSI-MS). This method of extraction can be coupled to Raman spectroscopy for supplemental verification of analytes using surface enhanced Raman scattering (SERS). The gold surface used for SERS provides an enhanced effect on peak signal intensity allowing ultra-trace amounts to be detected more effectively. The aim of this research is to utilize gold-coated films with electrostatic lifting in order to collect latent materials and analyze chemicals of interest contained in them via SERS., (Published by Elsevier Ireland Ltd.)

An expanding appreciation for the varied functions of neutral lipids in cellular organisms relies on a more detailed understanding of the mechanisms of lipid production and packaging into cytosolic lipid droplets (LDs). Conventional lipid profiling procedures involve the analysis of tissue extracts and consequently lack cellular or subcellular resolution. Here, we report an approach that combines the visualization of individual LDs, microphase extraction of lipid components from droplets, and the direct identification of lipid composition by nanospray mass spectrometry, even to the level of a single LD. The triacylglycerol (TAG) composition of LDs from several plant sources (mature cotton (Gossypium hirsutum) embryos, roots of cotton seedlings, and Arabidopsis thaliana seeds and leaves) were examined by direct organelle mass spectrometry and revealed the heterogeneity of LDs derived from different plant tissue sources. The analysis of individual LDs makes possible organellar resolution of molecular compositions and will facilitate new studies of LD biogenesis and functions, especially in combination with analysis of morphological and metabolic mutants. Furthermore, direct organelle mass spectrometry could be applied to the molecular analysis of other subcellular compartments and macromolecules.

An extension of current mobility resolution equations as they apply to high-field ion mobility spectrometry is presented. The new resolution expression is applied to arrival time distributions for ions having a large range of ion mobilities and mass-to-charge ratios (m/z). The results indicate that the new equation can be utilized to predict the mobility resolution over a broader range of applied electric fields than previous ion mobility resolution expressions.

Chemists are constantly striving for techniques that add dimensions of orthogonality with increased throughput and sample complexity. Ion mobility spectrometry (IM) is a gas-phase separation method that adds new dimensions to mass spectrometry (MS). IM separates gas-phase ions based on their collision cross-section and can be coupled with time-of-flight (TOF) mass spectrometry to yield a powerful tool used in the identification and characterization of proteins and peptides. A fundamental introduction to IM is presented with a focus on resolution, sensitivity, and orthogonality coupled with TOF-MS.