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Assessing the onset of calcium phosphate nucleation by hyperpolarized real-time NMR - Phys.org

"Nature unveiling herself before science," is a sculpture by Louis-Ernest Barrias on display at the Musée d'Orsay in Paris. A research collaboration of the University of Vienna and the Sorbonne in Paris now took this credo to heart. "In order to create effici…

"Nature unveiling herself before science," is a sculpture by Louis-Ernest Barrias on display at the Musée d'Orsay in Paris. A research collaboration of the University of Vienna and the Sorbonne in Paris now took this credo to heart. "In order to create efficient functional materials, nature offers the best recipes by providing evolutionarily successful concepts," says Dennis Kurzbach from the Institute of Biological Chemistry. Kurzbach and his colleagues applied a jointly developed technology, based on NMR spectroscopy, to reveal the secrets of biomineralisation. Closing gaps of precision NMR (nuclear magnetic resonance) is an important method to determine the structures of molecules in solution, albeit with limited resolution. In order to facilitate real-time monitoring of rapid chemical processes, Dennis Kurzbach and his team developed a new prototype that, based on hyperpolarisation (more specifically Dissolution Dynamic Nuclear Polarisation, D-DNP), provides the scientists with up to 10,000-fold amplified signals in NMR experiments. With this D-DNP prototype, the scientists can monitor processes taking place on the milliseconds timescale, while at the same time single atoms can be resolved. The prototype encompasses an already patented system to mix various interaction partners within milliseconds and to initiate real-time detection. Precipitation of ionic solids from solution Dennis Kurzbach, an expert in methods development, started the proof-of-concept with his Parisian colleague Thierry Azaïs, who was interested in a better understanding of the initial steps of biomineralisation. Using D-DNP monitoring, the scientists probed fast interaction kinetics such as those underlying the formation of pre-nucleation species that develop within milliseconds when calcium and phosphate ions meet in solution and that precede non-classical solid-liquid phase separation. "For the first time, we were able to analytically characterise these pre-nucleation species at high resolution," Kurzbach explains, who has established the cutting-edge technology in the NMR Core Facility of the Faculty of Chemistry within the framework of his ERC Starting Grant. With their new insights and technology, the researchers are also contributing material to a long-lasting dispute about the theory behind the biomineralisation of calcium phosphate. "Some researchers doubt that the pre-nucleation species can be integrated into the classical theoretical framework developed over decades," says Dennis Kurzbach. The researcher's study also provides a kick-off for a recently granted project funded by the Austrian Science Fund FWF, in which Kurzbach intends to use his technology to advance the characterisation of biominerals as well as of the initial chemical processes before nucleation. For example, he aims at clarifying whether the size of the newly discovered species is controllable and if so, whether it is possible to engineer future hardness or brittleness of the macroscopic material. "Moreover, it will be interesting to see whether we can help to solve the current theoretical shortcomings," Kurzbach says, who graduated not only in chemistry, but also in philosophy. "For me, our research goals are also strongly reflected by Aristoteles' ideas: All human beings strive by nature after knowledge." The D-DNP technology now makes it possible to deepen our knowledge of the nature of the materials, which provides important properties to people and society. More information: Emmanuelle Weber et al, Assessing the onset of calcium phosphate nucleation by hyperpolarized real-time NMR, Analytical Chemistry (2020). DOI: 10.1021/acs.analchem.0c00516 Citation: Assessing the onset of calcium phosphate nucleation by hyperpolarized real-time NMR (2020, May 19) retrieved 19 May 2020 from https://phys.org/news/2020-05-onset-calcium-phosphate-nucleation-hyperpolarized.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Scientists successfully develop 'heat resistant' coral to fight bleaching - Phys.org

The team included researchers from CSIRO, Australia's national science agency, the Australian Institute of Marine Science (AIMS) and the University of Melbourne.

The team included researchers from CSIRO, Australia's national science agency, the Australian Institute of Marine Science (AIMS) and the University of Melbourne. Corals with increased heat tolerance have the potential to reduce the impact of reef bleaching from marine heat waves, which are becoming more common under climate change. "Coral reefs are in decline worldwide," CSIRO Synthetic Biology Future Science Platform (SynBio FSP) science lead Dr. Patrick Buerger said. "Climate change has reduced coral cover, and surviving corals are under increasing pressure as water temperatures rise and the frequency and severity of coral bleaching events increase." The team made the coral more tolerant to temperature-induced bleaching by bolstering the heat tolerance of its microalgal symbiontstiny cells of algae that live inside the coral tissue. "Our novel approach strengthens the heat resistance of coral by manipulating its microalgae, which is a key factor in the coral's heat tolerance," Dr. Buerger said. The team isolated the microalgae from coral and cultured them in the specialist symbiont lab at AIMS. Using a technique called "directed evolution", they then exposed the cultured microalgae to increasingly warmer temperatures over a period of four years. This assisted them to adapt and survive hotter conditions. "Once the microalgae were reintroduced into coral larvae, the newly established coral-algal symbiosis was more heat tolerant compared to the original one," Dr. Buerger said. The microalgae were exposed to temperatures that are comparable to the ocean temperatures during current summer marine heat waves causing coral bleaching on the Great Barrier Reef. The researchers then unveiled some of the mechanisms responsible for the enhanced coral bleaching tolerance. "We found that the heat tolerant microalgae are better at photosynthesis and improve the heat response of the coral animal," Professor Madeleine van Oppen, of AIMS and the University of Melbourne, said "These exciting findings show that the microalgae and the coral are in direct communication with each other." Footage of a healthy coral reef with vibrant colors (min 00:03 00:10). Bleached corals with white skeletons that suffered from heat stress (00:10 00:20). Coral spawning releasing eggs and sperm bundles, wide shot (00:21 00:29). Coral spawning releasing eggs and sperm bundles, close up shot (00:29 00:38). Coral spawning laboratory work (00:38 00:44). Coral spawning in laboratory (00:44 00:55). Laboratory work (00:55 01:31). Coral larvae settling into a polyp (01:31 01:41). Coral poly (01:41 01:50). Credit: The Australian Institute of Marine Science (AIMS) and The Commonwealth Scientific and Industrial Research Organization (CSIRO) The next step is to further test the algal strains in adult colonies across a range of coral species. "This breakthrough provides a promising and novel tool to increase the heat tolerance of corals and is a great win for Australian science," SynBio FSP Director Associate Professor Claudia Vickers said. More information: P. Buerger el al., "Heat-evolved microalgal symbionts increase coral bleaching tolerance," Science Advances (2020). advances.sciencemag.org/content/6/20/eaba2498 Citation: Scientists successfully develop 'heat resistant' coral to fight bleaching (2020, May 13) retrieved 13 May 2020 from https://phys.org/news/2020-05-scientists-successfully-resistant-coral.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.