Genetic modification of tomato with the tobacco lycopene β-cyclase gene produces high β-carotene and lycopene fruit

Transgenic Solanum lycopersicum plants expressing an additional copy of the lycopene beta-cyclase gene (LCYB) from Nicotiana tabacum, under the control of the Arabidopsis polyubiquitin promoter (UBQ3), have been generated. Expression of LCYB was increased some 10-fold in ripening fruit compared to vegetative tissues. The ripe fruit showed an orange pigmentation, due to increased levels (up to 5-fold) of beta-carotene, with negligible changes to other carotenoids, including lycopene. Phenotypic changes in carotenoids were found in vegetative tissues, but levels of biosynthetically related isoprenoids such as tocopherols, ubiquinone and plastoquinone were barely altered. Transformants showed tolerance to the bleaching herbicide beta-cyclase inhibitor, 2-(4-chlorophenylthio) triethylamine. The phenotype was inherited for at least three generations

Antioxidant compounds and their bioaccessibility in tomato fruit and puree obtained from a DETIOLATED-1 (DET-1) down-regulated genetically modified genotype

[EN] The economic value, the ease of cultivation and processing, and the well-known health-promoting properties of tomato fruit, make the tomato an important target for genetic manipulation to increase its nutritional content. A transgenic variety, down-regulated in the DETIOLATED-1 (DET-1) gene, has been studied in comparison with the parental line, for antioxidant levels in fresh and hot break fruit, as well as the bioaccessibility of antioxidants from puree. Differences in the concentrations of antioxidants between the wild-type and the genetically modified raw tomatoes were confirmed, but antioxidant levels were maintained to a greater extent in the GM puree than in the parent. The bioaccessibility of the compounds, tested using an in vitro digestion model, showed an increase in the genetically modified samplesL. Mora and P. D. Fraser are grateful to the EU-FP7 Marie Curie Intra-European Fellowship scheme (FOOSAF project) for financial resources. P. Talens acknowledges the Universidad Politecnica de Valencia for the financial support of a fellowship at the Centre for Systems and Synthetic Biology, School of Biological Sciences of Royal Holloway, University of London. Addition funds were received from FP6-EU-SOL and FP7 METAPRO projects (to PDF and PMB)Talens Oliag, P.; Mora, L.; Bramley, PM.; Fraser, PD. (2016). Antioxidant compounds and their bioaccessibility in tomato fruit and puree obtained from a DETIOLATED-1 (DET-1) down-regulated genetically modified genotype. Food Chemistry. 213:735-741. https://doi.org/10.1016/j.foodchem.2016.06.079S73574121

Deep-ocean mineral deposits: metal resources and windows into earth processes

Deep-ocean mineral deposits could make a significant contribution to future raw material supply. Growing metal demand and geopolitics are focussing increasing attention on their resource potential and economic importance. However, accurate assessment of the total amounts of metal and its recoverability are very difficult. Deep-ocean mineral deposits also provide valuable windows through which to study the Earth, including the evolution of seawater and insights into the exchange of heat and chemicals between the crust and the oceans. Exploration for, and potential extraction of, deep-ocean mineral deposits poses many geological, technical, environmental and economic challenges, as well as regulatory and philosophical questions. Great uncertainty exists, and the development and stewardship of these deposits requires an incremental approach, encouraging transparency and scientific and civil societal input to balance the interests of all

Geochemical evidence of Milankovitch cycles in Atlantic Ocean ferromanganese crusts

Hydrogenetic ferromanganese crusts are considered a faithful record of the isotopic composition of seawater influenced by weathering processes of continental masses. Given their ubiquitous presence in all oceans of the planet at depths of 400–7000 meters, they form one of the most well-distributed and accessible records of water-mass mixing and climate. However, their slow accumulation rate and poor age constraints have to date limited their use to explore 100 ka paleoclimatic phenomena. Here it is shown how the Pb isotope signature and major element content of a Fe-Mn crust from the north-east Atlantic responded to changes in the intensity and geographic extent of monsoonal rainfall over West Africa, as controlled by climatic precession during the Paleocene. The studied high-spatial resolution (4 μm) laser-ablation multi-collector inductively coupled plasma mass spectrometer (LA-MC-ICP-MS) Pb isotope data is a nearly 2 order of magnitude improvement in spatial and temporal resolution compared to micro-drill subsamples. The record demonstrates cyclicity of the 206Pb/204Pb and 208, 207Pb/206Pb ratios at the scale of single Fe-Mn oxide laminae, in conjunction with variations in the Fe/Mn ratio, Al, Si and Ti content. Time-frequency analysis and astronomical tuning of the Pb isotope data demonstrates the imprint of climatic precession (∼20 ka) modulated by eccentricity (∼100 and 405 ka), yielding growth rates of 1.5–3.5 mm/Ma consistent with previous chemostratigraphic age models. In this context, boreal summer at the perihelion causes stronger insolation over West Africa, resulting in more intense and geographically extended monsoonal rainfalls compared to aphelion boreal summer conditions. This, in turn, influences the balance between the weathering endmembers feeding the north-east Atlantic basin. These results provide a new approach for calibrating Fe-Mn crust records to astronomical solutions, and allow their isotopic and chemical archive to be exploited with an improved temporal resolution of 1000–5000 years

La Proteómica como vía para determinar el origen animal de los productos cárnicos

Comunicaciones a congreso

Controls on metal enrichment in ferromanganese crusts: temporal changes in oceanic metal flux or phosphatisation?

Oceanic hydrogenetic ferromanganese (Fe-Mn) crusts are a major repository for many metals, such as Co, Ni, Cu, Pt, Te and REE, which are essential for decarbonisation of transport and energy systems. Secondary mineralisation processes, occurring during phosphatisation episodes, commonly impregnate the shallower deposits with carbonate fluorapatite (CFA). The suboxic oceanic conditions during such events are frequently invoked to explain the lower Co content and unusually high Ni, Cu, Zn and Pt content of older phosphatised crusts. Here, the hypothesis of suboxic diagenetic recrystallization induced by phosphatisation episodes as a driving mechanism for Ni, Cu, Zn and Pt enrichment and Co depletion is evaluated. Accurately dated geochemical profiles, spanning 75 Ma of depositional history, for a shallow (1100 mbsl) phosphatised sample and a deeper (3100 mbsl) unphosphatised sample from Tropic Seamount in the north-east Atlantic, are compared. An isocon analysis, which allows to quantitively evaluate chemical gains and losses in mass transfer and therefore permits compensation for the dilution effect induced by the addition of CFA in the Fe-Mn crusts, demonstrates that no loss of Co has occurred in the phosphatised crust, whilst Pt, Te, Cu, Ni and Zn are enriched relative to younger, unphosphatised Fe-Mn crust. Both geochemical profiles show sympathetic trends and similar amplitudes of variation in concentration. This excludes phosphatisation as the driving mechanism for the metal enrichment and depletion. Systematic differences in metal content between the two samples, such as higher Cu and lower Co content in the deeper sample, are consistent with the depth profile of dissolved metal concentrations in the water column. The variability observed in the geochemical profiles is consistent with temporal changes in metal fluxes to the ocean, as a result of the evolving climate and oceanographic configuration of the north-east Atlantic Ocean through the Cenozoic. It is concluded that changing metal fluxes, rather than secondary mineralisation process associated with phosphatisation, is the dominant control on the primary metal content in Fe-Mn crust deposits at Tropic Seamount

Late Cretaceous and Cenozoic paleoceanography from north-east Atlantic ferromanganese crust microstratigraphy

Oceanic hydrogenetic ferromanganese (Fe-Mn) crusts precipitate directly from ambient seawater over millions of years. Their very slow growth rates and physio-chemical properties mean that they adsorb numerous elements from seawater. As such, they provide condensed records of seawater evolution through time that can be used for paleoceanographic reconstruction. Here, we present the results of a high-resolution, stratigraphic, textural and geochemical investigation of a core sample, obtained from a Fe-Mn crust pavement, located on the summit of Tropic Seamount in the tropical north-east Atlantic Ocean. A number of observations and interpretations are proposed, within the context of a well-constrained age model, spanning the last 75 ± 2 Myr. This core has textural stratigraphic coherence with Pacific Fe-Mn crusts formed since the Late Cretaceous, highlighting that global oceanic and climatic phenomena exert first-order controls on Fe-Mn crust development. All major hiatuses observed in the Fe-Mn crusts are contemporaneous with erosion events occurring throughout the Atlantic Ocean. High-resolution geochemical data indicate that there is variability in the composition of Fe-Mn crusts at the cm to μm scale. The dominant factors controlling this include major oceanographic events, mineral textures and micro-topography