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Comment by Dr. Krishna Kumari Challa on November 7, 2020 at 6:52am

**SARS-CoV-2 uses 'genome origami' to infect and replicate inside host cells

Scientists at the University of Cambridge, in collaboration with Justus-Liebig University, Germany, have uncovered how the genome of SARS-CoV-2—the coronavirus that causes COVID-19—uses genome origami to infect and replicate successfully inside host cells. This could inform the development of effective drugs that target specific parts of the virus genome, in the fight against COVID-19.

Most current work to find drugs and vaccines for COVID-19 is focused on targeting the proteins of the virus. Because the shape of the RNA molecule is critical to its function, targeting the RNA directly with drugs to disrupt its structure would block the lifecycle and stop the virus replicating.

the team uncovered the entire structure of the SARS-CoV-2 genome inside the host cell, revealing a network of RNA-RNA interactions spanning very long sections of the genome. Different functional parts along the genome need to work together despite the great distance between them, and the new structural data shows how this is accomplished to enable the coronavirus life cycle and cause disease.

"The RNA genome of coronaviruses is about three times bigger than an average viral RNA genome—it's huge

In all cells the genome holds the code for the production of specific proteins, which are made when a molecular machine called a ribosome runs along the RNA reading the code until a 'stop sign' tells it to terminate. In coronaviruses, there is a special spot where the ribosome only stops 50% of the times in front of the stop sign. In the other 50% of cases, a unique RNA shape makes the ribosome jump over the stop sign and produce additional viral proteins. By mapping this RNA structure and the long-range interactions involved, the new research uncovers the strategies by which coronaviruses produce their proteins to manipulate our cells.

The genome of most human viruses is made of RNA rather than DNA. Ziv developed methods to investigate such long-range interactions across viral RNA genomes inside the host cells, in work to understand the Zika virus genome. This has proved a valuable methodological basis for understanding SARS-CoV-2.

 Omer Ziv et al, The short- and long-range RNA-RNA Interactome of SARS-CoV-2, Molecular Cell (2020). DOI: 10.1016/j.molcel.2020.11.004

https://phys.org/news/2020-11-sars-cov-genome-origami-infect-replic...

Comment by Dr. Krishna Kumari Challa on November 7, 2020 at 6:32am

**Has the hidden matter of the universe been discovered?

Astrophysicists consider that around 40% of the ordinary matter that makes up stars, planets and galaxies remains undetected, concealed in the form of a hot gas in the complex cosmic web. Today, scientists at the Institut d'Astrophysique Spatiale (CNRS/Université Paris-Saclay) may have detected, for the first time, this hidden matter through an innovative statistical analysis of 20-year-old data.

 H. T Tanimura et al. First detection of stacked X-ray emission from cosmic web filaments, Astronomy & Astrophysics (2020). DOI: 10.1051/0004-6361/202038521

https://phys.org/news/2020-11-hidden-universe.html?utm_source=nwlet...

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**Coronavirus testing finally gathers speed

The imminent large-scale rollout of rapid coronavirus tests promises to aid public health responses to COVID-19 — but a rapid home test remains elusive.

https://www.nature.com/articles/d41587-020-00021-z?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on November 7, 2020 at 6:21am

Gold-catalyzed reaction releases an active drug to kill cancer cells

Drugs that are activated inside the body with catalytic quantities of gold could offer a new option for treating cancer and other diseases.

Using metals to convert masked "prodrugs" into their active forms inside the body is an emerging area of biomedical research. These drug-release reactions are designed to be triggered by metals that are not naturally present in the body, providing a new way to trigger drug release that promises to increase the efficacy and reduce the side effects of a therapy.

Kenward Vong et al. Bioorthogonal release of anticancer drugs via gold-triggered 2-alkynylbenzamide cyclization, Chemical Science (2020). DOI: 10.1039/d0sc04329j

https://phys.org/news/2020-11-gold-catalyzed-reaction-drug-cancer-c...

Comment by Dr. Krishna Kumari Challa on November 7, 2020 at 6:18am

Seeing dark matter in a new light

A small team of astronomers have found a new way to 'see' the elusive dark matter haloes that surround galaxies, with a new technique 10 times more precise than the previous-best method.

Scientists currently estimate that up to 85% of the mass in the universe is effectively invisible. This "dark matter" cannot be observed directly, because it does not interact with light in the same way as the ordinary matter that makes up stars, planets, and life on Earth.

So how do we measure what cannot be seen? The key is to measure the effect of gravity that the dark matter produces. It's like looking at a flag to try to know how much wind there is. You cannot see the wind, but the flag's motion tells you how strongly the wind is blowing.

The new research focuses on an effect called weak gravitational lensing, which is a feature of Einstein's general theory of relativity. The dark matter will very slightly distort the image of anything behind it.

Weak gravitational lensing is already one of the most successful ways to map the dark matter content of the Universe. Now, the team has used the ANU 2.3m Telescope in Australia to map how gravitationally lensed galaxies are rotating. Because we know how stars and gas are supposed to move inside galaxies, we know roughly what that galaxy should look like. By measuring how distorted the real galaxy images are, then we can figure out how much dark matter it would take to explain what we see. The new research shows how this velocity information enables a much more precise measurement of the lensing effect than is possible using shape alone.

Pol Gurri et al. The first shear measurements from precision weak lensing, Monthly Notices of the Royal Astronomical Society (2020). DOI: 10.1093/mnras/staa2893

https://phys.org/news/2020-11-dark.html?utm_source=nwletter&utm...

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 8:18am

The Science Communication Crisis

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 8:13am

 2020 Heroes of Chemistry

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 8:05am

Startling Case Study Finds Asymptomatic COVID-19 Carrier Who Shed Virus For 70 Days

A team of researchers and doctors has now reported the case of one woman with leukemia who had no symptoms of COVID-19 but 70 days after her first positive test, she was still shedding infectious SARS-CoV-2 particles.

This result is much longer than previous reports of hospitalised adults found shedding infectious SARS-CoV-2 virus up to 20 days after their COVID-19 diagnosis, plus other accounts of people shedding genetic material from the virus up to 63 days after their symptoms first appeared.

The new report should alert doctors and public health experts alike to the fact that people without symptoms and with weakened immune systems, such as cancer patients, can seemingly shed the SARS-CoV-2 virus for a really long time. In this case, even months.

"Although it is difficult to extrapolate from a single patient, our data suggest that long-term shedding of infectious virus may be a concern in certain immunocompromised patients," the research team wrote in their paper describing the case.

https://www.cell.com/cell/fulltext/S0092-8674(20)31456-2

https://www.sciencealert.com/case-study-reveals-rare-patient-who-sh...

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 7:54am

How Some Vaccines Protect Against More than Their Targets

As researchers test existing vaccines for nonspecific protection against COVID-19, immunologists are working to understand how some inoculations protect against pathogens they weren’t designed to fend off.

https://www.the-scientist.com/features/how-some-vaccines-protect-ag...

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 6:47am

New research traces the origins of trench fever

First observed among British Expeditionary Forces in 1915, trench fever sickened an estimated 500,000 soldiers during World War I. Since then, the disease has become synonymous with the battlefield. But now, new research from an international team of scientists has uncovered evidence challenging this long-held belief.

The research, published this week in PLOS ONE, outlines the discovery of DNA evidence of the disease in civilian remains predating WWI by thousands of years. In total, the team analyzed bone fragments and teeth of 145 individuals alive between the 1st and 19th centuries. Approximately 20% of those remains contained traces of Bartonella quintana, the bacteria responsible for trench fever. 

Epidemiologists and researchers used real-time polymerase chain reaction testing to detect B. quintana DNA within the remains.

Once contracted, there are diseases, like trench fever, that can leave traces within your DNA and can integrate your DNA with further information. This means that once a person dies, even as far back as 2,000 years ago, it is still possible to find traces of the bacterium that infected them.

 The discovery sheds light on the complex history of trench fever and begins answering historical questions about the lives of people in this region during the 3rd and 4th centuries.

While most associate this disease with WWI and WWII, occurrences of trench fever are still reported today, most prominently within homeless populations. The bacteria are spread to humans through contact with body lice (Pediculus humanus corporis), making poor personal hygiene a primary factor in its spread and infection rate. Researchers hope that by tracing the progression of B. quintana through history, they're able to identify ways to better manage the spread of the disease today.

Ba-Hoang-Anh Mai et al, Five millennia of Bartonella quintana bacteraemia, PLOS ONE (2020). DOI: 10.1371/journal.pone.0239526

https://phys.org/news/2020-11-trench-fever.html?utm_source=nwletter...

Comment by Dr. Krishna Kumari Challa on November 6, 2020 at 6:40am

The biggest trees capture the most carbon: Large trees dominate carbon storage in forests

Older, large-diameter trees have been shown to store disproportionally massive amounts of carbon compared to smaller trees, highlighting their importance in mitigating climate change, according to a new study in Frontiers in Forests and Global Change.

 They found that despite only accounting for 3% of the total number of trees on the studied plots, large trees stored 42% of the total above-ground carbon within these forest ecosystems. This study is among the first of its kind to report how a proposed policy could affect carbon storage in forest ecosystems, potentially weakening protections for large-diameter trees and contributing to huge releases of carbon dioxide to the atmosphere in the face of a changing climate.

Frontiers in Forests and Global Change, DOI: 10.3389/ffgc.2020.594274 , www.frontiersin.org/articles/1 … fgc.2020.594274/full

https://phys.org/news/2020-11-biggest-trees-capture-carbon-large.ht...

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