Pinus pinaster early hormonal defence responses to pinewood nematode (Bursaphelenchus xylophilus) infection

The pinewood nematode (PWN) is the causal agent of pine wilt disease, a pathology that affects conifer forests, mainly Pinus spp. PWN infection can induce the expression of phytohormone-related genes; however, changes at the early phytohormone level have not yet been explored. Phyto-hormones are low-abundance metabolites, and thus, difficult to quantify. Moreover, most method-ologies focus mainly on Arabidopsis or crop species. This work aimed to validate a fast (run time 6.6 min) liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS/MS) analytical method to quantify 14 phytohormones in Pinus pinaster stem tissues. This method was further applied to evaluate, for the first time, early phytohormone changes in susceptible and resistant phenotypes of P. pinaster 24, 48 and 72 h after inoculation (HAI) with PWN. A significant increase in salicylic acid (SA, 48 and 72 HAI) and jasmonic acid methyl ester (JA-ME, 72 HAI) was observed in susceptible phenotypes. Results indicate that the higher susceptibility of P. pinaster to PWN infection might result from an inefficient trigger of hypersensitive responses, with the involvement of JA and SA pathways. This work provides an important update in forest research, and adds to the current knowledge of Pinus spp. defence responses to PWN infection

The genomic and enzymatic basis for iridoid biosynthesis in cat thyme (Teucrium marum)

Iridoids are non-canonical monoterpenoids produced by both insects and plants. An example is the cat-attracting and insect-repelling volatile iridoid nepetalactone, produced by Nepeta sp. (catmint) and aphids. Recently, both nepetalactone biosynthetic pathways were elucidated, showing a remarkable convergent evolution. The iridoid, dolichodial, produced by Teucrium marum (cat thyme) and multiple insect species, has highly similar properties to nepetalactone but its biosynthetic origin remains unknown. We set out to determine the genomic, enzymatic, and evolutionary basis of iridoid biosynthesis in T. marum. First, we generated a de novo chromosome-scale genome assembly for T. marum using Oxford Nanopore Technologies long reads and proximity-by-ligation Hi-C reads. The 610.3 Mb assembly spans 15 pseudomolecules with a 32.9 Mb N50 scaffold size. This enabled identification of iridoid biosynthetic genes, whose roles were verified via activity assays. Phylogenomic analysis revealed that the evolutionary history of T. marum iridoid synthase, the iridoid scaffold-forming enzyme, is not orthologous to typical iridoid synthases but is derived from its conserved paralog. We discovered an enzymatic route from nepetalactol to diverse iridoids through the coupled activity of an iridoid oxidase cytochrome P450 and acetyltransferases, via an inferred acylated intermediate. This work provides a genomic resource for specialized metabolite research in mints and demonstration of the role of acetylation in T. marum iridoid diversity. This work will enable future biocatalytic or biosynthetic production of potent insect repellents, as well as comparative studies into iridoid biosynthesis in insects

Pelagic Sargassum events in Jamaica : Provenance, morphotype abundance, and influence of sample processing on biochemical composition of the biomass

Pelagic Sargassum species have been known for centuries in the Sargasso Sea of the North Atlantic Ocean. In 2011, a new area concentrating high biomass of these brown algae started developing in the Tropical Atlantic Ocean. Since then, massive and recurrent Sargassum influxes have been reported in the Caribbean and off the coast of Western Africa. These Sargassum events have a major negative impact on coastal ecosystems and nearshore marine life, and affect socio-economic sectors, including public health, coastal living, tourism, fisheries, andmaritime transport. Despite recent advances in the forecasting of Sargassum events, and elucidation of the seaweed composition, many knowledge gaps remain, including morphotype abundance during Sargassum events, drift of the seaweeds in the months prior to stranding, and influence of sample processing methods on biomass biochemical composition. Using seaweeds harvested on the coasts of Jamaica in summer of 2020,we observed that S. fluitans III was themost abundantmorphotype at different times and sampling locations. No clear difference in the geographical origin, or provenance, of the Sargassummats was observed. Themajority of Sargassumbacktracked fromboth north and south of Jamaica experienced ambient temperatures of around 27 °C and salinity in the range of 34–36 psu before stranding.We also showed that cheap (sun) compared to expensive (freeze) drying techniques influence the biochemical composition of biomass. Sun-drying increased the proportion of phenolic compounds, but had a deleterious impact on fucoxanthin content and on the quantities of monosaccharides, except for mannitol. Effects on the content of fucose containing sulfated polysaccharides depended on the method used for their extraction, and limited variation was observed in ash, protein, and fatty acid content within most of the sample locations investigated. These observations are important for the storage and transport of the biomass in the context of its valorisation

Genetic architecture of glucosinolate variation in Brassica napus

The diverse biological activities of glucosinolate (GSL) hydrolysis products play significant biological and economical roles in the defense system and nutritional qualities of Brassica napus (oilseed rape). Yet, genomic-based study of the B. napus GSL regulatory mechanisms are scarce due to the complexity of working with polyploid species. To address these challenges, we used transcriptome-based GWAS approach, Associative Transcriptomics (AT), across a diversity panel of 288 B. napus genotypes to uncover the underlying genetic basis controlling quantitative variation of GSLs in B. napus vegetative tissues. Single nucleotide polymorphism (SNP) markers and gene expression markers (GEMs) associations identify orthologues of MYB28/HAG1 (AT5G61420), specifically the copies on chromosome A9 and C2, to be the key regulators of aliphatic GSL variation in leaves. We show that the positive correlation observed between aliphatic GSLs in seed and leaf is due to the amount synthesized, as controlled by Bna.HAG1.A9 and Bna.HAG1.C2, rather than by variation in the transport processes. In addition, AT and differential expression analysis in root tissues implicate an orthologue of MYB29/HAG3 (AT5G07690), Bna.HAG3.A3, as controlling root aromatic GSL variation. Based on the root expression data we also propose Bna.MAM3.A3 to have a role in controlling phenylalanine chain elongation for aromatic GSL biosynthesis. This work uncovers a regulator of homophenylalanine-derived aromatic GSLs and implicates the shared biosynthetic pathways between aliphatic and aromatic GSLs

German S3 guideline "actinic keratosis and cutaneous squamous cell carcinoma" – long version of the update 2023

Actinic keratosis (AK) are common lesions in light-skinned individuals that can potentially progress to cutaneous squamous cell carcinoma (cSCC). Both conditions may be associated with significant morbidity and constitute a major disease burden, especially among the elderly. To establish an evidence-based framework for clinical decision making, the guideline “actinic keratosis and cutaneous squamous cell carcinoma” was updated and expanded by the topics cutanepus squamous cell carcinoma in situ (Bowen’s disease) and actinic cheilitis. This guideline was developed at the highest evidence level (S3) and is aimed at dermatologists, general practitioners, ear nose and throat specialists, surgeons, oncologists, radiologists and radiation oncologists in hospitals and office-based settings, as well as other medical specialties, policy makers and insurance funds involved in the diagnosis and treatment of patients with AK and cSCC

Cocoa and tea flavanols and cardiovascular health

Flavanol-rich dark chocolate (DC) and green tea extract capsules (GT) were assessed for effects on markers of vascular health. Commercially available dark chocolate was analysed for flavanol and methylxanthine levels using HPLC. There was considerable variation between brands of high cocoa solid content, and epicatechin (EC) levels did not correlate with calculated % non-fat cocoa solids. EC-rich DC also had considerably high methylxanthine levels. EC-rich DC was used to assess acute endothelial fitness. EndoPAT index (PAT) was determined in fingertips (3 subjects). PAT was not affected by dark chocolate ingestion, but systolic blood pressure (SBP) increased significantly by 5.2±4.9 mmHg (p<O.04). In a further intervention study (3 subjects), no correlation was observed between flow-mediated dilation (FMD) and PAT before or after DC ingestion. Neither FMD nor PAT were affected by acute DC intake while SBP increased (+10.2±8.6 mmHg, p=O.058). Augmentation index (Alx) and• pulse wave velocity (PWV) remained constant. Acute FMD improved significantly by 2.8±2.0% (p<O.02) after intake of GT in another intervention study (6 subjects). DC, or DC and GT co-ingested, had no effect on FMD. SBP (+3.9±4.1 mmHg, p<O.05) and diastolic BP (DBP) (+4.1 ±2.9 mmHg, p<O.02) increased significantly after DC intake but not after GT, or DC and GT combined. Alx, PWV and area-under-the-shear-rate- curve remained unaffected by either dietary intervention. 5-hour urine specimen displayed higher concentrations of EC, 3'-O-methyl- EC and 4'-O-methyl-EC following intake of DC than GT, or DC and GT combined. No correlation was present between urinary flavanol metabolites and endothelial fitness markers. The presence of flavanols in the test foods may have been the underlying cause for FMD improvement following GT ingestion. After DC consumption, the beneficial effects of EC may have been counteracted by the pressor effects of the methylxanthines, which consistently led to BP increases in all 3 studies after DC ingestion.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The influence of juicing on the appearance of blueberry metabolites 2 h following consumption: a metabolite profiling approach

The consumption of berries has been linked to decreased risk of degenerative disease. Berries are regularly processed into juices. It is largely unknown how the juicing process affects the bioavailability of metabolites. As metabolomics has shown to be a valuable nutritional tool to study global metabolite differences, the aim of the present study was to investigate the effect of juicing on the relative appearance of blueberry metabolites in humans using metabolomics. Nine healthy subjects consumed 250g of fresh blueberries either as the whole fruit or following juicing, and provided blood and urine samples before and 2h following intake in a crossover design. Samples underwent metabolite profiling using LCMS, and data was mined with multivariate analysis. Overall, less than 12% of all ions detected were significantly influenced by blueberry treatment (P<0.05). PLS-DA models of post treatment samples revealed good discrimination. In urinary samples, whole blueberry treatment resulted in 108 ions that were significantly higher compared to juiced treatment (positive and negative mode combined) while only 8 were significantly higher following juiced treatment. Examples of putative annotations included metabolites of ferulic and caffeic acids, several phenolic metabolites conjugated to sulfate, glycoside or glucuronide and fatty acyl derivatives, which were higher intensity following whole blueberry treatment. In conclusion, consumption of whole blueberries resulted in a higher range of phenolic and other metabolites in plasma and urine samples 2h following consumption. Both whole and juiced blueberries resulted in very similar metabolite profiles at 2h although this was the only time point measured

Improved furfural tolerance in Escherichia coli mediated by heterologous NADH-dependent benzyl alcohol dehydrogenases

While lignocellulose is a promising source of renewable sugars for microbial fermentations, the presence of inhibitory compounds in typical lignocellulosic feedstocks, such as furfural, has hindered their utilisation. In Escherichia coli, a major route of furfural toxicity is the depletion of NADPH pools due to its use as a substrate by the YqhD enzyme that reduces furfural to its less toxic alcohol form. Here, we examine the potential of exploiting benzyl alcohol dehydrogenases as an alternative means to provide this same catalytic function but using the more abundant reductant NADH, as a strategy to increase the capacity for furfural removal. We determine the biochemical properties of three of these enzymes, from Pseudomonas putida, Acinetobacter calcoaceticus, and Burkholderia ambifaria, which all demonstrate furfural reductase activity. Furthermore, we show that the P. putida and B. ambifaria enzymes are able to provide substantial increases in furfural tolerance in vivo, by allowing more rapid conversion to furfuryl alcohol and resumption of growth. The study demonstrates that methods to seek alternative cofactor dependent enzymes can improve the intrinsic robustness of microbial chassis to feedstock inhibitors