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Sugars, ‘gum,’ stardust found in NASA’s asteroid Bennu samples

The asteroid Bennu continues to provide new clues to scientists’ biggest questions about the formation of the early solar system and the origins of life. As part of the ongoing study of pristine samples delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft, three new papers published Tuesday by the journals Nature Geosciences and Nature Astronomy present remarkable discoveries: sugars essential for biology, a gum-like substance not seen before in astromaterials, and an unexpectedly high abundance of dust produced by supernova explosions.

Scientists led by Yoshihiro Furukawa of Tohoku University in Japan found sugars essential for biology on Earth in the Bennu samples, detailing their findings in the journal Nature Geoscience. The five-carbon sugar ribose and, for the first time in an extraterrestrial sample, six-carbon glucose were found. Although these sugars are not evidence of life, their detection, along with previous detections of amino acids, nucleobases, and carboxylic acids in Bennu samples, show building blocks of biological molecules were widespread throughout the solar system.

For life on Earth, the sugars deoxyribose and ribose are key building blocks of DNA and RNA, respectively. DNA is the primary carrier of genetic information in cells. RNA performs numerous functions, and life as we know it could not exist without it. Ribose in RNA is used in the molecule’s sugar-phosphate “backbone” that connects a string of information-carrying nucleobases.

Sunlight, water and air power a cleaner method for making hydrogen peroxide

Cornell scientists have discovered a potentially transformative approach to manufacturing one of the world’s most widely used chemicals—hydrogen peroxide—using nothing more than sunlight, water and air. The research is published in the journal Nature Communications.

“Currently, hydrogen peroxide is made through the anthraquinone process, which relies on fossil fuels, produces chemical waste and requires transport of concentrated peroxide—all of which have safety and environmental concerns,” said Alireza Abbaspourrad, associate professor of Food Chemistry and Ingredient Technology in the Department of Food Science in the College of Agriculture and Life Sciences, and corresponding author of the research.

Hydrogen peroxide is ubiquitous in both industrial and consumer settings: It bleaches paper, treats wastewater, disinfects wounds and household surfaces, and plays a key role in electronics manufacturing. Global production runs into the millions of tons each year. Yet today’s process depends almost entirely on a complex method involving hazardous intermediates and large-scale central chemical plants.

Zapping stem cells could boost growth of new tissues and organs

Scientists in Melbourne have discovered how tiny electrical pulses can steer stem cells as they grow, opening the door to new improved ways of creating new tissues, organs, nerves and bones.

Dr. Amy Gelmi, a senior lecturer at RMIT University’s School of Science, led the work using advanced atomic force microscopy to track how stem cells change their structure when exposed to electrical stimulation.

The study reveals, for the first time, how living stem cells physically respond to external signals in real time—reshaping themselves within minutes and setting off changes that influence what type of cell they eventually become. The paper is published in the journal Advanced Materials Interfaces.

X-ray laser offers new look at protein movement inside cells

At European XFEL, researchers have observed in detail how the vital iron protein ferritin makes its way in highly dense environments—with implications for medicine and nanotechnology.

Inside biological cells, there is a dense crowd where millions of proteins move side by side, bump into each other or temporarily accumulate. At the same time, these proteins often have to fulfill important tasks at short notice. How exactly the proteins move in this confined space has been difficult to track until now.

An international research team led by Anita Girelli and Fivos Perakis, both from Stockholm University, has now used the European XFEL X-ray laser in Schenefeld near Hamburg to take a closer look at these movements—and discovered a surprising pattern. The results are published in Nature Communications.

Impaired touch perception in Alzheimer’s associated with Tau pathology and lower cognitive scores

Alzheimer’s disease (AD) is a neurodegenerative condition characterized by the progressive deterioration of brain cells, which prompts memory loss, a decline in mental functions and behavioral changes. Estimates suggest that this disease affects approximately 1 in 14 people who are more than 65 years old and over 35% of people who are over 85 years old.

Due to its prevalence and debilitating nature, AD has become the focus of numerous neuroscience and medical studies. Most of these studies examined brain regions and neurogenetic processes that appear to be different in people diagnosed with AD.

Recently, some neuroscientists gathered evidence suggesting that parts of the brain that support somatosensory processing (i.e., the interpretation of tactile stimuli, pressure and the body’s position in space), are also affected in individuals with AD. Yet the extent to which these tactile sensation-related deficits play a role in the cognitive decline typical of AD has not yet been determined.

Glassed-in DNA makes the ultimate time capsule

Year 2015 face_with_colon_three


IF YOU must preserve messages for people in the far future to read, Blu-ray discs and USB sticks are no good. For real long-term storage, you want a DNA time capsule.

Just 1 gram of DNA is theoretically capable of holding 455 exabytes – enough for all the data held by Google, Facebook and every other major tech company, with room to spare. It’s also incredibly durable: DNA has been extracted and sequenced from 700,000-year-old horse bones. But conditions have to be right for it to last.

A rhythmically pulsing leaf-spring DNA-origami nanoengine that drives a passive follower

DNA nano machine year 2023.


An autonomous DNA-origami nanomachine powered by the chemical energy of DNA-templated RNA-transcription-consuming nucleoside triphosphates as fuel performs rhythmic pulsations is demonstrated. In combination with a passive follower, the nanomachine acts as a mechanical driver with molecular precision.

P-Rex1 limits the agonist-induced internalization of GPCRs independently of its Rac-GEF activity

P-Rex1 activates Rac downstream of GPCRs to regulate processes ranging from innate immunity to neuronal plasticity, its deregulation contributing to cancer. Here, Baker et al. show that P-Rex1 also controls GPCR trafficking, limiting agonist-induced GPCR internalization through an adapter function. Thus, P-Rex1 promotes GPCR responses in a dual manner.

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