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Chemists offer more evidence of RNA as the origin of life

first_img Citation: Chemists offer more evidence of RNA as the origin of life (2016, May 13) retrieved 18 August 2019 from https://phys.org/news/2016-05-chemists-evidence-rna-life.html (Phys.org)—A team of chemists at Ludwig Maximilian University of Munich has shown how the purines adenine and guanine can be synthesized easily and in reasonable yields, offering more evidence that RNA could have served as the origin of life on Earth. In their paper published in the journal Science, the team describes the process they took in looking for evidence that RNA could have been the first self-replicating molecule that eventually led to all life on our planet and what they found. Journal information: Science 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. For several years many scientists have supported the idea that life got its start on our planet due to a series of events that led to the creation of RNA molecules—it seems like a strong candidate because it is able to both store information and act as a catalyst. To bolster the theory, scientists have been trying to show under what conditions RNA might have come about based on the conditions that existed on early Earth. In the early going, researchers found it relatively easy to show how two of the four main building blocks in RNA, uracil and cytosine, could have come about, but showing how the other two, adenine and guanine, might have come about has been problematic. In this new effort the research team describes a scenario under with both might have come about given conditions at the time that life is believed to have got its start.The team started by extending prior research that had shown that a molecule called formamidopyrimidine can react under certain conditions to form purines—they discovered that adding acid to an amine (which the team showed could have come about very easily from plentiful carbon, nitrogen and hydrogen) allowed for a reaction that led to the formation of a purine and that it would easily bond with formic acid, which recent research has shown is plentiful on comets—that means it could have met with existing purines if a comet crashed into the planet at the right place. Once that happened, the resultant reactions would have led to forging bonds with sugars which would have resulted in the creation of large amounts of purines, including adenine and guanine—thus all of the necessary ingredients would have been in place for the creation of RNA molecules, setting the stage for the development of living organisms. This is a computer graphic of an RNA molecule. Credit: Richard Feldmann/Wikipediacenter_img © 2016 Phys.org Missing links brewed in primordial puddles? Explore further More information: S. Becker et al. A high-yielding, strictly regioselective prebiotic purine nucleoside formation pathway, Science (2016). DOI: 10.1126/science.aad2808AbstractThe origin of life is believed to have started with prebiotic molecules reacting along unidentified pathways to produce key molecules such as nucleosides. To date, a single prebiotic pathway to purine nucleosides had been proposed. It is considered to be inefficient due to missing regioselectivity and low yields. We report that the condensation of formamidopyrimidines (FaPys) with sugars provides the natural N-9 nucleosides with extreme regioselectivity and in good yields (60%). The FaPys are available from formic acid and aminopyrimidines, which are in turn available from prebiotic molecules that were also detected during the Rosetta comet mission. This nucleoside formation pathway can be fused to sugar-forming reactions to produce pentosides, providing a plausible scenario of how purine nucleosides may have formed under prebiotic conditions.last_img read more

CRYing need to get them to school

first_imgChild Rights and You, India’s leading Child 30th rights NGO and its alliance, APR – Alliance for People’s Rights, organised a day long theatre festival in the capital.This was an open forum for children to speak out on issues that affect them the most in school. Shiksha Hamara Haq theme of the festival amplified the voices of more than 50 children between ages 6-14 from different parts of city. Corporal punishment and discrimination, barriers in education due to lack of infrastructure, positive impact of RTE Act are the issues which the festival addressed. Also Read – ‘Playing Jojo was emotionally exhausting’Padhna isi ka naam hai, Dhoondte reh jaoge, Thoda hai thode kee zarurat hai, were three plays where children showcased what they have observed as issues of basic infrastructure in their school, hygiene and access to playgrounds. The theatre festival was followed up by a panel discussion on the status of education in Delhi. Themes of the discussion were, ensuring enrolment of all children between 6-14 years in school, as per the current provisions of RTE Act, 2009, ensuring that no child is subjected to any kind of corporal punishment of any nature- physical or mental, To ensure ‘compulsory education’ for all children through availability of a neighbourhood school with proper infrastructure.last_img read more

Bookworms are usually friendlier

first_imgIn some good news for bookworms, scientists have found that people who regularly read fiction novels are more likely to be friendly, well-behaved and sympathetic towards others.Those who prefer watching television over reading are less sociable, according to the study. Those who like reading of drama and romance novels were best able to understand other people, while those who preferred experimental books showed more positive social behaviour and ability to see things from different perspectives. Also Read – Add new books to your shelf”The findings support previous evidence that exposure to fiction relates to a range of empathetic abilities,” said Rose Turner, from Kingston University in the UK.Researchers at Kingston University questioned 123 people on their preferences for books, TV and plays.The volunteers were then tested on their interpersonal skills and prosocial behaviour – such as whether they considered other’s feelings, whether they could see things from different points of view and whether they acted to help others. Also Read – Over 2 hours screen time daily will make your kids impulsiveResearchers found people who preferred reading novels were more likely to show positive social behaviour and be able to empathise with others.However, those who preferred watching TV did not have the same ability to empathise and were more likely to show antisocial behaviour.Comedy fans scored the highest for being able to relate to others, The Sun reported.Researchers suggest that this could be because reading books allow people to see things from other’s points of view, which makes them better able to understand others.”All forms of fiction are not equal. Associations between empathetic skills, media and genre diverge,” said Turner.”Engaging with fictional prose and comedy in particular could be key to enhancing people’s empathetic abilities,” she said.last_img read more