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Comment by Dr. Krishna Kumari Challa on March 22, 2022 at 11:41am

In their study, published in Nature Microbiology today, the scientists analyzed data from 12,000 microbial communities from all over the world, provided by the Earth Microbiome Project.

Within these groups of different microorganisms, which live together producing and absorbing materials they all need to survive and grow, the researchers found one type in particular was highly prevalent. Auxotrophs, which are unable to create essential metabolites, like amino acids, vitamins or fatty acids, were present in 99.95% of the 12,538 communities they studied.

The widespread nature of auxotrophs has been considered a paradox, a fundamental problem in our understanding of microbiology. This is because they must absorb metabolites from the environment and so they have been thought of as weaker than other cells which can create these chemical compounds themselves. They have been seen as scrounger cells, a drain on communal resources.

By analyzing drug exposure data from the project, the scientists found that communities with auxotrophs are more likely to have tolerance against hundreds of drugs, than communities without these cells. Moreover, the research showed that they are not scrounger cells, but rather cooperative partners as, in exchange for taking up metabolites that are essential for them, they return other metabolites to the community.

Further experiments using a yeast model showed that this increased tolerance is because cells that cooperate in metabolism, have increased levels of metabolic export, the movement of metabolites out of cells. As a side-effect, this also causes drugs to be moved out of cells at a higher rate.

Part 2

Comment by Dr. Krishna Kumari Challa on March 22, 2022 at 11:39am

Microbial communities where cells cooperate have increased drug tolerance

New research  has revealed a key mechanism which increases tolerance to drugs amongst microbial communities. The findings could help the development of more effective antifungal treatments.

Antimicrobial drug resistance and tolerance occurs when bacteria, viruses, fungi or parasites no longer respond, or have less sensitivity, to treatments. It is a major issue within medicine, for example, invasive fungal infections are responsible for 1.6 million deaths annually.

Around the world, more people die each year from invasive fungal species than from malaria. There are currently only three classes of antifungal drugs in clinical use and in an increasing number of cases, these antifungals fail. Understanding the mechanisms which increase or decrease the chance of a drug working is crucial to aid the developments of new treatments.
Part 1

Comment by Dr. Krishna Kumari Challa on March 22, 2022 at 11:36am

Scientists discover how molecule becomes anticancer weapon

Years of toil in the laboratory have revealed how a marine bacterium makes a potent anti-cancer molecule.

The anti-cancer molecule salinosporamide A, also called Marizomb, is in Phase III clinical trials  to treat glioblastoma, a brain cancer. Scientists now for the first time understand the enzyme-driven process that activates the molecule.

Researchers found that an enzyme called SalC assembles what the they call the salinosporamide anti-cancer "warhead." 

The work solves a nearly 20-year riddle about how the marine bacterium makes the warhead that is unique to the salinosporamide molecule and opens the door to future biotechnology to manufacture new anti-cancer agents.

Now that scientists understand how this enzyme makes the salinosporamide A warhead, that discovery could be used in the future to use enzymes to produce other types of salinosporamides that could attack not only cancer but diseases of the immune system and infections caused by parasites.

 Bradley Moore, Enzymatic assembly of the salinosporamide γ-lactam-β-lactone anticancer warhead, Nature Chemical Biology (2022). DOI: 10.1038/s41589-022-00993-w. www.nature.com/articles/s41589-022-00993-w

https://phys.org/news/2022-03-scientists-molecule-anticancer-weapon...

Comment by Dr. Krishna Kumari Challa on March 21, 2022 at 8:32am

How to clean solar panels without water

Comment by Dr. Krishna Kumari Challa on March 21, 2022 at 8:26am

Smoke from major wildfires destroys the ozone layer, study shows

 A new study shows that smoke from wildfires destroys the ozone layer. Researchers caution that if major fires become more frequent with a changing climate, more damaging ultraviolet radiation from the sun will reach the ground.

Atmospheric chemists found that smoke from the Australian wildfires of 2019 and 2020 destroyed atmospheric ozone in the Southern Hemisphere for months. The ozone shield is a part of the stratosphere layer of the Earth's atmosphere that absorbs UV rays from the sun.

The researchers used data from the Canadian Space Agency's Atmospheric Chemistry Experiment (ACE) satellite to measure the effects of smoke particles in the stratosphere. The results appear in the journal Science.

The Australian fires injected acidic smoke particles into the stratosphere, disrupting the chlorine, hydrogen and nitrogen chemistry that regulate ozone. This is the first large measurement of the smoke, which shows it converting these ozone-regulating compounds into more reactive compounds that destroy ozone.

Similar to the holes over polar regions, this damage is a temporary effect, and the ozone levels returned to pre-wildfire levels once the smoke disappeared from the stratosphere. But an increase in the prevalence of wildfires would mean the destruction happens more often.

https://www.science.org/doi/10.1126/science.abm5611

Comment by Dr. Krishna Kumari Challa on March 21, 2022 at 8:08am

The lead author on the paper is Dr. Paula Byrne from the HRB Centre for Primary Care Research based in RCSI's Department of General Practice. Commenting on the findings, Dr. Byrne says that "the message has long been that lowering your cholesterol will reduce your risk of heart disease, and that statins help to achieve this. However, our research indicates that, in reality, the benefits of taking statins are varied and can be quite modest."

The researchers go on to suggest that this updated information should be communicated to patients through informed clinical decision-making and updated clinical guidelines and policy.

This important discovery was a collaboration with Professor Susan M Smith, also of RCSI and with researchers from the University of New Mexico, USA, (Dr. Robert DuBroff), the Institute for Scientific Freedom in Denmark (Dr. Maryanne Demasi), Bond University in Australia (Dr. Mark Jones) and independent researcher Dr. Kirsty O'Brien.

Evaluating the Association Between Low-Density Lipoprotein Cholesterol Reduction and Relative and Absolute Effects of Statin Treatment, JAMA Internal Medicine (2022). DOI: 10.1001/jamainternmed.2022.0134

https://medicalxpress.com/news/2022-03-link-high-cholesterol-heart-...

Part 2

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Comment by Dr. Krishna Kumari Challa on March 21, 2022 at 8:07am

Link between high cholesterol and heart disease 'inconsistent', new study finds

New research from RCSI University of Medicine and Health Sciences has revealed that the link between 'bad' cholesterol (LDL-C) and poor health outcomes, such as heart attack and stroke, may not be as strong as previously thought.

Published in JAMA Internal Medicine, the research questions the efficacy of statins when prescribed with the aim of lowering LDL-C and therefore reducing the risk of cardiovascular disease (CVD).

Previous research has suggested that using statins to lower LDL-C positively affects health outcomes, and this is reflected in the various iterations of expert guidelines for the prevention of CVD. Statins are now commonly prescribed by doctors, with one third of Irish adults over the age of 50 taking statins, according to previous research.

The new findings contradict this theory, finding that this relationship was not as strong as previously thought. Instead, the research demonstrates that lowering LDL-C using statins had an inconsistent and inconclusive impact on CVD outcomes such as myocardial infarction (MI), stoke, and all-cause mortality. 

In addition, it indicates that the overall benefit of taking statins may be small and will vary depending on an individual's personal risk factors.

Part 1

Comment by Dr. Krishna Kumari Challa on March 21, 2022 at 8:00am

Sponges, not just their microbes, make biologically potent compounds

Marine sponges are incredible sources of structurally diverse and biologically active natural products. The development of secondary metabolites isolated from sponges into FDA approved drugs is well precedented, with representative examples such as the antiviral nucleoside, vidarabine, and the potent anticancer drug, eribulin mesylate, used in treatment of late-stage, metastatic breast cancer. Despite these success stories, the pharmaceutical industry has largely abandoned efforts to identify bioactive compounds from sponges due to challenges associated with the sustainable sourcing of raw material for extraction, chemical modification of intricate architectures, and overall lack of precedent regarding how sponges assemble these secondary metabolites. The San Diego intertidal and subtidal zones are home to an incredibly rich taxonomic diversity of sponges, presenting a unique opportunity to apply modern genomic and metabolomic approaches to identify new, bioactive scaffolds and decrypt their biosynthetic origin. We profiled over 20 species of sponges local to San Diego using classical and feature-based molecular networking, as well as examined the variation of microbial symbionts across phyla using culture-dependent and independent methods. Our access to fresh, local samples enabled our identification of a variety of novel, bioactive compounds and glean new insights into their genetic origin and environmental role in host-microbe interactions.

https://www.eurekalert.org/news-releases/945819

Comment by Dr. Krishna Kumari Challa on March 19, 2022 at 11:57am

Scientists discover a new kind of cell death linked to copper

Copper is an essential element of life from bacteria and fungi to plants and animals. In humans, it binds to enzymes to help blood clot, hormones mature, and cells process energy. But too much copper kills cells—and now scientists have figured out how.

Copper is a double-edged sword: too little and cells can't survive. But too much, and cells die.

Researchers have uncovered a new form of cell death that is induced by copper.

found that copper binds to specialized proteins, causing them to form harmful clumps, and also interferes with the function of other essential proteins. Cells go into a state of toxic stress and ultimately die.

By shedding light on key components of this process, the research also identified which cells are particularly vulnerable to copper-induced death. The findings could help researchers better understand diseases in which copper is dysregulated, and could even inform the development of new cancer treatments. 

 Peter Tsvetkov et al, Copper induces cell death by targeting lipoylated TCA cycle proteins, Science (2022). DOI: 10.1126/science.abf0529

https://phys.org/news/2022-03-scientists-kind-cell-death-linked.htm...

Comment by Dr. Krishna Kumari Challa on March 19, 2022 at 11:51am

Researchers discover new form of ice

 Researchers have discovered a new form of ice, redefining the properties of water at high pressures.

Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

A team of scientists  pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds—freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals.

By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X.

the transition to Ice-X, when water stiffens aggressively, occurs at much lower pressures than previously thought.

While it's unlikely we'll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system.

Zachary M. Grande et al, Pressure-driven symmetry transitions in dense H2O ice, Physical Review B (2022). DOI: 10.1103/PhysRevB.105.104109

https://phys.org/news/2022-03-ice.html?utm_source=nwletter&utm_...

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