Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: chemistry – Page 8

How one RNA nucleotide switch activates fluorescent dyes

RhoBAST is a tiny RNA molecule that activates fluorescent dyes, enabling researchers to track RNA molecules in living cells with super-resolution. An international collaboration, which includes Ronald Micura and his team from the Institute of Organic Chemistry, has now shown that a small, local “nucleotide flip” within the RNA controls this fluorescence activation.

Fluorescent light-up aptamers (FLAPs) are short RNA sequences that bind and activate small dye molecules that otherwise exhibit only weak fluorescence. This enables genetic tagging of RNAs for live-cell imaging without the need for protein fusion markers. Because the dye is only “switched on” upon binding to the RNA, background fluorescence remains low.

Systems such as Spinach, Broccoli, Mango and Pepper have continuously advanced this principle over the past years. RhoBAST additionally enables high-resolution imaging of individual RNA molecules in living cells.

Brain aging may be detected decades before symptoms appear, with links to gut health

A new UCLA study has found a connection between how quickly the brain ages and the bacteria and chemical byproducts found in the gut, offering a clue to what drives brain aging long before symptoms appear.

Researchers have long used brain scans to estimate a person’s “brain age,” a measure that can differ from someone’s actual age in years. When a brain looks older than expected on a scan, prior research has linked it to poorer memory, thinking skills and mood. However, most of these studies involved older adults or people with existing brain diseases. Whether this gap between brain age and chronological age means anything in younger, generally healthy people has been unclear.

In a new study published in the journal eBioMedicine, UCLA Health researchers analyzed brain scans from nearly 1,500 adults across three separate groups using a method that measures how different regions of the brain communicate with one another while at rest.

Unusual bonds reorganize structure and magnetism in vanadium material

While chemical bonds usually determine the structure and properties of a material, bonds between neighboring metal atoms can also change as temperature or other conditions change. These changes can lead to unusual electronic and magnetic behaviors.

A new study on Li₀.₅VS₂ shows that bonding between vanadium atoms can reorganize as the material passes through successive structural changes. The study was led by assistant professor Keita Kojima from the Graduate School of Environment, Life, Natural Science and Technology at Okayama University in Japan, along with professor Naoyuki Katayama from Okayama University.

The study is published in the journal Chemistry of Materials.

Unveiling how nanoparticles create iridescence in ancient ceramics

Scientists led by the Universitat Politècnica de Barcelona and the ESRF, the European Synchrotron, have revealed the chemical reactions in nanoparticles that created a unique, shimmering effect in the painting on ninth-century Islamic ceramics. The results are published in Science Advances.

Many centuries before the rise of nanotechnology, ninth-century Abbasid potters were producing ceramics with striking colors (golden, red, brown or yellow) and a metallic appearance resulting from nanoparticles. This technology, which created the iridescent effect, emerged in the Near East during the Abbasid period and subsequently spread across the Islamic world.

“Today we still find it very difficult to reproduce the effects they did in the ninth century, so we wanted to find out what chemical transformation the paint applied to the ceramics went through to create such effects,” explains Trinitat Pradell, professor at the Universitat Politècnica de Barcelona and co-corresponding author of the publication.

First PLP-dependent enzyme that influences bacterial protein production discovered

Researchers from the Singapore-MIT Alliance for Research & Technology’s (SMART) Antimicrobial Resistance (AMR) interdisciplinary research group, alongside collaborators from Massachusetts Institute of Technology (MIT), Nanyang Technological University (NTU Singapore), and institutions in the United States, Poland and France, have discovered aminovaleramididine synthetase (AvaS), the first identified pyridoxal phosphate (PLP)-dependent enzyme responsible for producing a chemical modification linked to how bacteria respond to metabolic stress.

This fundamental discovery sheds new light on how bacteria use RNA modification to control protein production, opening new avenues to study bacterial adaptation and identify future targets for antimicrobial therapeutics.

Antimicrobial resistance is one of the most pressing global health and development challenges of our time. Bacteria and other pathogens are rapidly developing resistance to existing treatments, making infections harder to treat. Without new approaches, minor inconveniences today, such as routine surgeries or even a paper cut, could become life-threatening tomorrow.

Scientists May Have Cracked the Mystery of the Moon’s Unequal Hemispheres

Chang’e-6 samples suggest the Moon’s two very different sides may have formed when uneven heating drove magma from one hemisphere to the other.

The Moon presents two dramatically different faces. Its Earth-facing hemisphere is rich in dark volcanic plains, while the farside is dominated by older highlands and a much thicker crust. New analyses of material returned by Chang’e-6 (CE6) suggest that this contrast may trace back to enormous flows within the Moon’s early magma ocean after it became tidally locked to Earth.

Led by Professor Hejiu Hui of Nanjing University, the research team carried out detailed geochemical analyses of anorthosites, Mg-suite rocks, and mare basalts collected from the lunar farside. They then compared those samples with material from the nearside returned by the Apollo and Chang’e-5 missions.

Tiny molecular rings open new ways for designing better medicines

Cyclopropanes are organic chemistry’s smallest rings. Three carbon atoms are joined in a triangle, creating a compact and unusually strained structure. Despite—or partly because of—this unusual geometry, cyclopropanes are found in many biologically active natural products and have important applications in medicines and drug discovery, from antidepressants to antibiotics and antiviral research.

Connect these carbon triangles to an amine, a functional group with a nitrogen at its center, and you get aminocyclopropanes. They are of particular interest in pharmaceutical research because they can be used to replace another substructure commonly found in drug molecules: α,α-gem-dimethylamines (compounds in which the aminocyclopropane’s triangle is “opened” by disconnecting one edge).

Such molecular substitutes that resemble an existing part of a drug but can alter important properties, such as biological activity and metabolic stability, are referred to as bioisosteres and have shown beneficial effects in countless cases.

Untangling the meta-biomaterial puzzle one property at a time

From repairing damaged tissues to developing better implants, many medical developments depend on materials that can mimic the complex properties of human tissue. Meta-biomaterials are among the most promising candidates. By tailoring their geometry, researchers can create materials with properties similar to those of natural tissues. But there is a catch: Changing one property often changes several others at the same time. TU Delft scientists have now developed a method to decouple these properties.

Their work, published in Nature Communications, helps researchers understand how individual material properties influence cell behavior and could accelerate the development of next-generation biomaterials.

Meta-biomaterials are engineered materials whose properties are determined not by their chemical composition but by their internal architecture. This allows researchers to design structures with carefully tuned mechanical, morphological and mass-transport properties. Such control is particularly valuable in biomedical engineering, where materials need to do more than simply replace damaged tissue. They must also interact with cells and actively support tissue regeneration.

Super-resolution imaging reveals details inside living cells

A new fluorescence microscopy technique that generates super-resolution images from a single camera exposure could help researchers study rapid movements within cells that are difficult to capture with existing methods.

Super-resolution microscopy has transformed cell biology by allowing scientists to see cellular structures and details that are too small to be imaged clearly with conventional light microscopes. Some methods achieve super-resolution by combining information from hundreds or thousands of image frames taken over time.

However, this works best when biological samples like cells or tissues have been fixed, or preserved with chemicals. Otherwise, structures like mitochondria, microtubules and DNA—which are constantly moving, changing and interacting—appear blurry using existing super-resolution techniques.

Stripped-down LSD reveals structural features linked to hallucinogenic and therapeutic effects

University of California, Davis, researchers have stripped down LSD to the base features responsible for its hallucinogenic and therapeutic effects.

In a study published in Proceedings of the National Academy of Sciences, the researchers whittled away at LSD’s core multiring structure and synthesized new, simplified versions to probe its functionality. The researchers developed several compounds with reduced hallucinogenic and cardiotoxic effects while identifying one compound that produced antipsychotic-like effects.

“By systematically deconstructing LSD, we have identified simplified cores that are better starting points for medicinal chemistry efforts,” said study corresponding author David E. Olson, director of the Institute for Psychedelics and Neurotherapeutics and a professor of chemistry and biochemistry and molecular medicine at UC Davis.

/* */