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Comment by Dr. Krishna Kumari Challa on February 22, 2022 at 11:50am

Bacteria upcycle carbon waste into valuable chemicals

Bacteria are known for breaking down lactose to make yogurt and sugar to make beer. Now researchers have harnessed bacteria to break down waste carbon dioxide (CO₂) to make valuable industrial chemicals.

In a new pilot study, the researchers selected, engineered and optimized a bacteria strain and then successfully demonstrated its ability to convert CO₂ into acetone and isopropanol (IPA).

Not only does this new gas fermentation process remove greenhouse gases from the atmosphere, it also avoids using fossil fuels, which are typically needed to generate acetone and IPA. After performing life-cycle analysis, the team found the carbon-negative platform could reduce greenhouse gas emissions  by 160% as compared to conventional processes, if widely adopted.

 Michael Jewett, Carbon-negative production of acetone and isopropanol by gas fermentation at industrial pilot scale, Nature Biotechnology (2022). DOI: 10.1038/s41587-021-01195-w. www.nature.com/articles/s41587-021-01195-w

https://phys.org/news/2022-02-bacteria-upcycle-carbon-valuable-chem...

Comment by Dr. Krishna Kumari Challa on February 22, 2022 at 11:47am

Tough and stretchable ionogels

Silent speech device developed

Comment by Dr. Krishna Kumari Challa on February 21, 2022 at 10:01am

Researchers conducted experiments using human cells and a mouse model mimicking the cytokine storm seen in some patients with severe COVID-19 infection. They applied CRISPR genome-wide screening to analyze how cell function, in particular cell death, changes when one gene is knocked out (inactivated).

Receptor-interacting protein kinase (RIPK1) plays a critical role in regulating inflammation and cell death. Many sites on this protein are modified when a phosphate is added (a process known as phosphorylation) to suppress RIPK1's cell death-promoting enzyme activity. How the phosphate is removed from RIPK1 sites (dephosphorylation) to restore cell death is poorly understood. This new work discovered that PPP1R3G recruits phosphatase 1 gamma (PP1γ) to directly remove the inhibitory RIPK1 phosphorylations blocking RIPK1's enzyme activity and cell death, thereby promoting apoptosis and necroptosis.

An  analogy of a car brake help explain what's happening with the balance of cell survival and death in this study: RIPK1 is the engine that drives the cell death machine (the car). Phosphorylation applies the brake (stops the car) to prevent cells from dying. The car (cell death machinery) can only move forward if RIPK1 dephosphorylation is turned on by the PPP1R3G protein complex, which releases the brake.

In this case, phosphorylation inhibits the cell death function of protein RIPK1, so more cells survive. Dephosphorylation takes away the inhibition, allowing RIPK1 to activate its cell death function.

The researchers showed that a specific protein-protein interaction—that is, PPP1R3G binding to PP1γ—activates RIPK1 and cell death. Furthermore, using a mouse model for "cytokine storm" in humans, they discovered knockout mice deficient in Ppp1r3g were protected against tumor necrosis factor-induced systemic inflammatory response syndrome. These knockout mice had significantly less tissue damage and a much better survival rate than wildtype mice with the same TNF-induced inflammatory syndrome and all their genes intact.

Overall, the study suggests that inhibitors blocking the PPP1R3G/PP1γ pathway can help prevent or reduce deaths and severe damage from inflammation-associated diseases, including heart disease, autoimmune disorders and COVID-19. They are working to screen and identify peptide compounds that most efficiently inhibit the PPP1R3G protein complex. They hope to pinpoint promising drug candidates that may stop the massive destruction of cardiac muscle cells caused by heart attacks.

Jingchun Du, Yougui Xiang, Hua Liu, Shuzhen Liu, Ashwani Kumar, Chao Xing, Zhigao Wang. RIPK1 dephosphorylation and kinase activation by PPP1R3G/PP1γ promote apoptosis and necroptosis. Nature Communications, 2021; 12 (1) DOI: 10.1038/s41467-021-27367-5

https://researchnews.cc/news/11713/Researchers-identify-protein-com...

Part 2

Comment by Dr. Krishna Kumari Challa on February 21, 2022 at 10:00am

Researchers identify protein complex critical in helping control cell death

 Cell death plays an important role in normal human development and health but requires tightly orchestrated balance to avert disease. Too much can trigger a massive inflammatory immune response that damages tissues and organs. Not enough can interfere with the body's ability to fight infection or lead to cancer.

Researchers are studying the complex molecular processes underlying necroptosis, which combines characteristics of apoptosis (regulated or programmed cell death) and necrosis (unregulated cell death).

During necroptosis dying cells rupture and release their contents. This sends out alarm signals to the immune system, triggering immune cells to fight infection or limit injury. Excessive necroptosis can be a problem in some diseases like stroke or heart attack, when cells die from inadequate blood supply, or in severe COVID-19, when an extreme response to infection causes organ damage or even death.

A new preclinical study  identifies a protein complex critical for regulating apoptosis and necroptosis—known as protein phosphatase 1 regulatory subunit 3G/protein phosphatase 1 gamma (PPP1R3G/PP1γ, or PPP1R3G complex). The researchers' findings suggest that an inhibitor targeting this protein complex may help reduce or prevent excessive necroptosis.

Cell death is very complicated process, which requires layers upon layers of brakes to prevent too many cells from dying. If you want to protect cells from excessive death, then the protein complex  identified in this study is one of many steps you must control.

Part 1

Comment by Dr. Krishna Kumari Challa on February 20, 2022 at 12:18pm

Comment by Dr. Krishna Kumari Challa on February 20, 2022 at 11:41am

In the computer simulations, PE particles were found to prefer the center of the lipid membrane as their location. In the PAMPA experiments, PE plastic partially permeated the membrane, but membrane permeability slowed down significantly over time, probably due to the accumulation of plastic in the membrane. In the simulations, the preferred location of PET particles was, to a certain degree, the surface part of the membrane, and in the experiments, they permeated the membrane fairly well. According to this study, the properties of the membrane structures were not significantly affected by individual plastics.

Joni Järvenpää et al, PE and PET oligomers' interplay with membrane bilayers, Scientific Reports (2022). DOI: 10.1038/s41598-022-06217-4

https://phys.org/news/2022-02-nano-sized-plastics-permeate-cell-mem...

Part 2

Comment by Dr. Krishna Kumari Challa on February 20, 2022 at 11:39am

Nano-sized plastics may enter and permeate cell membranes

The occurrence of microplastics in nature has been studied extensively. However, little is known about the health effects of microplastics, and understanding of their transport into the human body is also lacking. Any adverse health effects possibly associated with plastics may be caused by the plastic compound itself, or by the environmental toxins it carries. Many known fat-soluble environmental toxins and heavy metals are known to be able to attach to the surface of small plastic particles. This is why it is important to investigate the transport mechanisms of microplastics into the human body.

With the help of molecular modeling, researchers at the University of Eastern Finland's School of Pharmacy analyzed the behavior and transport of nano-sized microplastics in bilayer membranes which mimic cell membranes. The researchers performed simple molecular dynamics simulations using well-known and widely used polyethylene (PE) and polyethylene terephthalate (PET) particles.

The cell membrane permeability of pulverized PE and PET plastics was also examined using the Parallel Artificial Membrane Permeability Assay method, PAMPA. The method is usually used to investigate passive absorption of medicines, but it hasn't been used to study microplastics before. The PAMPA method was used to investigate the amount of matter permeating the membrane. The amount of plastic permeating the artificial membrane was measured by NMR spectroscopy at certain intervals.

In both experiments, the movement of molecules was controlled only by concentration differences on different sides of the membrane, and by occasional movement induced by heat. In other words, the methods provided information on the passive permeation of molecules through the membranes.

Part 1

Comment by Dr. Krishna Kumari Challa on February 19, 2022 at 12:58pm

Scientists Convert Donor Lungs to Universal Blood Type in a Medical First

Patients can wait a long time for potentially life-saving lung transplants, since the need to find close matches complicates the process. One of the characteristics that need to be matched is patient and donor blood type.

Now new research shows that the blood type of some donated lungs could be altered before transplant, which means there is a bigger pool of universal donor lungs and less time on the waiting list for those in need.

The process works via a pair of enzymes – specifically, FpGalNAc deacetylase and FpGalactosaminidase – that in combination remove the antigens that distinguish red blood cells, converting blood type A lungs into universal type O.

Under lab conditions, scientists treated eight blood type A lungs with the enzyme combination, reporting that 97 percent of blood type A antigens were removed within four hours. What's more, the conversion was achieved without any observable toxicity.

Three of the newly 'neutral' lungs were then placed in plasma to simulate an actual transplant. Observed antibody damage was minimal, meaning the converted lungs were accepted rather than rejected, at least in the crucial, early stages.

The team estimates that the procedure could eventually increase the number of blood group O donor lungs from the current 55 percent to more than 80 percent in the future.

https://www.science.org/doi/10.1126/scitranslmed.abm7190?adobe_mc=M...

https://www.sciencealert.com/lungs-converted-to-a-universal-blood-t...

Comment by Dr. Krishna Kumari Challa on February 19, 2022 at 12:22pm

Mosquitos learn to avoid pesticides after single non-lethal exposure

Female mosquitoes learn to avoid pesticides after a single exposure, according to a study published in Scientific Reports. The authors suggest that this could make pesticides less effective against mosquitoes.

Pesticides are used to limit the spread of mosquito-transmitted diseases. Pesticide resistance has increased among mosquitoes in recent decades, however the extent to which this is due to mosquito behavior has been unclear.

Researchers exposed female Aedes aegypti and Culex quinquefasciastus mosquitoes—which transmit dengue, Zika and West Nile fever—to non-lethal doses of the common anti-mosquito pesticides malathion, propoxur, deltamethrin, permethrin and lambda-cyhalothrin. They then tested whether subsequent exposure to the same pesticide deterred mosquitoes from feeding and resting, and assessed whether this affected mosquito survival.

The researchers found that mosquitoes that had been pre-exposed to a pesticide avoided passing through a pesticide-treated net in order to reach a food source at a higher rate than those who had not been pre-exposed. Only 15.4% of A. aegypti and 12.1% of C. quinquefasciastus that had been pre-exposed passed through the net in order to feed, compared to 57.7% of A. aegypti and 54.4% of C. quinquefasciastus that had not been pre-exposed. Subsequently, the survival rate of pre-exposed mosquitoes was more than double that of mosquitoes that had not been pre-exposed. 38.3% of A. aegypti and 32.1% of C. quinquefasciastus that had been pre-exposed and 11.5% of A. aegypti and 12.9% C. quinquefasciastus that had not been pre-exposed survived exposure to the pesticide-treated net.

The researchers also found that pre-exposed mosquitoes were more likely than mosquitoes that had not been pre-exposed to a pesticide to rest in a container that smelt of a control substance, rather than in a container that smelt of a pesticide. 75.7% of A. aegypti and 83.1% of C. quinquefasciastus that had been pre-exposed to a pesticide rested in the pesticide-free container, compared to 50.2% of A. aegypti and 50.4% of C. quinquefasciastus that had not been pre-exposed.

The findings suggest that mosquitoes that have been exposed to non-lethal doses of pesticides learn to avoid these pesticides and, as a result, may seek out safer food sources and resting sites, allowing them to survive to reproduce.

https://www.nature.com/articles/s41598-022-05754-2

https://researchnews.cc/news/11682/Mosquitos-learn-to-avoid-pestici...

Comment by Dr. Krishna Kumari Challa on February 19, 2022 at 12:19pm

Research discovery could enable broad coronavirus vaccine

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