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Archive for the ‘chemistry’ category: Page 212

Sep 8, 2020

New structural unit simplifies the process of custom-designing proteins

Posted by in categories: biotech/medical, chemistry

The new structure works by mapping the backbones of amino acids to locations of chemicals in the Protein Data Bank involved in interactions with them. The researchers note that only recently has the data bank come to hold enough information to allow for its use in such an application. And they also note that the technique and structure can also be used to produce delivery vehicles based on proteins and also small molecule applications…


A pair of researchers at the University of California, San Francisco, has developed a new protein structure that allows for simplifying the process of custom-designing proteins. In their paper published in the journal Science, Nicholas Polizzi and William DeGrado discuss their structural unit and how they used it. Anna Peacock, with the University of Birmingham, has published a Perspective piece outlining the work by the team in California in the same journal issue.

One of the things that chemists are asked to do is custom design proteins for use in certain special applications. As the researchers note, doing so is considered to be very challenging. It usually involves a considerable amount of trial and error which generally translates to high development costs. In this new effort, the researchers have devised a new unit of to help with such projects. They call it a van der Mer and describe how it can be used to directly map ligand chemical group functionality to peptide residue backbone coordinates.

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Sep 8, 2020

Physicists nudge atoms within less than a trillionth of a second

Posted by in categories: biological, chemistry, particle physics, quantum physics, solar power, sustainability

Scientists from Regensburg and Zurich have found a fascinating way to push an atom with controlled forces so quickly that they can choreograph the motion of a single molecule within less than a trillionth of a second. The extremely sharp needle of their unique ultrafast microscope serves as the technical basis: It carefully scans molecules, similar to a record player. Physicists at the University of Regensburg now showed that shining light pulses onto this needle can transform it into an ultrafast “atomic hand.” This allows molecules to be steered—and new technologies can be inspired.

Atoms and are the constituents of virtually all matter that surrounds us. Interacting with each other according to the rules of quantum mechanics, they form complex systems with an infinite variety of functions. To examine , in a cell, or new ways of solar energy harvesting, scientists would love to not only observe individual molecules, but even control them.

Most intuitively, people learn by haptic exploration, such as pushing, pulling, or tapping. Naturally, we are used to macroscopic objects that we can directly touch, squeeze or nudge by exerting forces. Similarly, atoms and molecules interact via forces, but these forces are extreme in multiple respects. First, the forces acting between atoms and molecules occur at extremely small lengths. In fact, these objects are so small that a special length scale has been introduced to measure them: 1 Ångström (1Å = 0.000,000,000,1 m). Second, at the same time, atoms and molecules move and wiggle around extremely fast. In fact, their motion takes place faster than picoseconds (1 ps = 0.000,000,000,001 s). Hence, to directly steer a molecule during its motion, a tool is required to generate ultrafast forces at the atomic scale.

Sep 8, 2020

Plant protein discovery could reduce need for fertilizer

Posted by in categories: chemistry, climatology, nanotechnology, sustainability

Researchers have discovered how a protein in plant roots controls the uptake of minerals and water, a finding which could improve the tolerance of agricultural crops to climate change and reduce the need for chemical fertilizers.

The research, published in Current Biology, shows that members of the blue copper proteins family, the Uclacyanins are vital in the formation of Casparian strips. These strips are essential structures that control mineral nutrient and water use efficiencies by forming tight seals between cells in plants, blocking nutrients and water leaking between.

This is the first evidence showing the implications of this family in the biosynthesis of lignin, one of the most abundant organic polymers on earth. This study reveals that the required for Casparian strip lignin deposition is highly ordered by forming nano-domains which can have a huge impact on plant nutrition, a finding that could help in the development of crops that are efficient in taking in the nutrients they need.

Sep 8, 2020

Electronically integrated, mass-manufactured, microscopic robots

Posted by in categories: chemistry, robotics/AI

Fifty years of Moore’s law scaling in microelectronics have brought remarkable opportunities for the rapidly evolving field of microscopic robotics1,2,3,4,5. Electronic, magnetic and optical systems now offer an unprecedented combination of complexity, small size and low cost6,7, and could be readily appropriated for robots that are smaller than the resolution limit of human vision (less than a hundred micrometres)8,9,10,11. However, a major roadblock exists: there is no micrometre-scale actuator system that seamlessly integrates with semiconductor processing and responds to standard electronic control signals. Here we overcome this barrier by developing a new class of voltage-controllable electrochemical actuators that operate at low voltages (200 microvolts), low power (10 nanowatts) and are completely compatible with silicon processing. To demonstrate their potential, we develop lithographic fabrication-and-release protocols to prototype sub-hundred-micrometre walking robots. Every step in this process is performed in parallel, allowing us to produce over one million robots per four-inch wafer. These results are an important advance towards mass-manufactured, silicon-based, functional robots that are too small to be resolved by the naked eye.

Sep 6, 2020

Engineers Genetically Reprogram Yeast Cells to Become Microscopic Drug Factories

Posted by in categories: biotech/medical, chemistry, food, genetics

Since antiquity, cultures on nearly every continent have discovered that certain plant leaves, when chewed or brewed or rubbed on the body, could relieve diverse ailments, inspire hallucinations or, in higher dosages, even cause death. Today, pharmaceutical companies import these once-rare plants from specialized farms and extract their active chemical compounds to make drugs like scopolamine for relieving motion sickness and postoperative nausea, and atropine, to curb the drooling associated with Parkinson’s disease or help maintain cardiac function when intubating COVID-19 patients and placing them on ventilators.

Now, Stanford engineers are recreating these ancient remedies in a thoroughly modern way by genetically reprogramming the cellular machinery of a special strain of yeast, effectively transforming them into microscopic factories that convert sugars and amino acids into these folkloric drugs, in much the same way that brewers’ yeast can naturally convert sugars into alcohol.

Sep 5, 2020

Molecule’s electronic structure is simulated on a quantum computer

Posted by in categories: chemistry, computing, quantum physics

Simulating chemical processes is one of the most promising applications of quantum computers, but problems with noise have prevented nascent quantum systems from outperforming conventional computers on such tasks. Now, researchers at Google have taken a major step towards this goal by using the most powerful quantum computer yet built to successfully implement a protocol for calculating the electronic structure of a molecule. The results may form a blueprint for complex, useful calculations on quantum computers affected by noise.

In October 2019, Google announced to great fanfare that its 53-qubit Sycamore computer had achieved quantum advantage. This means that a quantum computer can solve at least one problem much faster than any conventional supercomputer. However, Google researchers openly acknowledged that the problem Sycamore solved (sampling the outcome of a random quantum circuit) is easy for a quantum computer but difficult for a conventional supercomputer — and had little practical use.

What researchers would really like to do is use quantum computers to solve useful problems more effectively than possible with conventional computers: “Sycamore is extremely programmable and, in principle, you really can run any algorithm on it…In this sense, it’s a universal quantum computer,” explains team member Ryan Babbush of Google Research, “However, there’s a heavy caveat: there’s still noise affecting the device and as a result we’re still limited in the size of circuit we can implement.” Such noise, which results from classical sources such as thermal interference, can destroy the fragile superpositions crucial to quantum computation: “We can implement a completely universal circuit before the noise catches up and eventually destroys the computation,” says Babbush.

Sep 4, 2020

Correcting anode-free cell failure to enable higher-energy-density batteries

Posted by in categories: chemistry, energy, sustainability, transportation

Batteries with high energy densities could enable the creation of a wider range of electric vehicles, including flying vehicles that can transport humans in urban environments. Past studies predict that to support the operation of vehicles capable of take-off and landing, batteries require energy densities of approximately 400 Wh kg-1 at the cell level, which is approximately 30% higher than the energy density of most existing lithium-ion (Li-ion) cells.

In addition to powering flying vehicles, high-energy (i.e., single units within a battery that convert chemical into ) could increase the distance that electric cars can travel before they need to be charged again. They may also reduce overall fabrication costs for electric vehicles, as similar results could be achieved using fewer but better-performing cells.

Anode-free lithium metal cells are particularly promising for creating batteries with higher energy densities. While they use the same cathode as Li-ion cells, these cells store energy via an electroplated lithium metal instead of a graphite host, and they can have energy densities that are 60% greater than those of Li-ion cells.

Sep 4, 2020

Decades-old mystery of lithium-ion battery storage solved

Posted by in categories: chemistry, mobile phones, sustainability, transportation

For years, researchers have aimed to learn more about a group of metal oxides that show promise as key materials for the next generation of lithium-ion batteries because of their mysterious ability to store significantly more energy than should be possible. An international research team, co-led by The University of Texas at Austin, has cracked the code of this scientific anomaly, knocking down a barrier to building ultra-fast battery energy storage systems.

The team found that these possess unique ways to store energy beyond classic electrochemical mechanisms. The research, published in Nature Materials, found several types of compounds with up to three times the energy storage capability compared with materials common in today’s commercially available lithium-ion batteries.

By decoding this mystery, the researchers are helping unlock batteries with greater energy capacity. That could mean smaller, more powerful batteries able to rapidly deliver charges for everything from smartphones to electric vehicles.

Sep 4, 2020

Google’s Quantum Computer Achieves Chemistry Milestone

Posted by in categories: chemistry, computing, quantum physics

A downsized version of the company’s Sycamore chip performed a record-breaking simulation of a chemical reaction.

Sep 4, 2020

The moon is rusty, and it’s likely Earth’s fault

Posted by in categories: chemistry, space

The moon is turning ever so slightly red, and it’s likely Earth’s fault. Our planet’s atmosphere may be causing the moon to rust, new research finds.

Rust, also known as an iron oxide, is a reddish compound that forms when iron is exposed to water and oxygen. Rust is the result of a common chemical reaction for nails, gates, the Grand Canyon’s red rocks — and even Mars. The Red Planet is nicknamed after its reddish hue that comes from the rust it acquired long ago when iron on its surface combined with oxygen and water, according to a statement from NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.