Lightsources.org virtual symposium recording

Lightsources.org was delighted to welcome over 500 attendees to our live virtual symposium to mark the 75th Anniversary of the first direct observation of synchrotron light in a laboratory. The event, which was chaired by Sandra Ribeiro, Chair of lightsources.org and Communications Advisor for the Canadian Light Source, was held on the 28th April 2022 and you can watch the recording via the YouTube link below.

We received some lovely feedback after the live event, including this comment from Jeffrey T Collins at the Advanced Photon Source, Argonne National Laboratory in Illinois.

 “I have worked at the Advanced Photon Source for over 32 years and I learned many things during this event that I never knew before.  It was quite informative.  I look forward to re-watching the entire event.”

Jeffrey T Collins, Mechanical Engineering & Design Group Leader at Argonne National Laboratory

The symposium began with a historical introduction from Roland Pease, freelance science broadcaster who has been an enthusiastic support of light sources for many years.

Roland’s talk was followed by experts from the field giving talks on their perspectives of synchrotron light related achievements that have been made since the 1st laboratory observation on the 24th April 1947.

Speakers were:

• Nobel Laureate Prof. Ada Yonath (Weizmann Institute of Science)

• Prof. Sir Richard Catlow (University College London)

• Prof. Henry Chapman (DESY)

• Dr Paul Tafforeau (ESRF)

• Dr Gihan Kamel (SESAME and member of the AfLS Executive Committee).

There followed a panel discussion with special guests who all made huge contributions to the development of the field. Our special guests were:

Herman Winick – Prof. of Applied Physics (Research) Emeritus at SLAC)

Ian Munro – Initiator of synchrotron radiation research at Daresbury Laboratory ,Warrington UK in 1970

Giorgio Margaritondo – one of the pioneers in the use of synchrotron radiation and free electron lasers

Gerd Materlik – former CEO of Diamond Light Source, the UK’s synchrotron science facility

Lightsources.org is hugely grateful to all the speakers, special guests and attendees who contributed to this event and made it such a special anniversary celebration for the light source community.

If you have any feedback or memories to share, please do contact Silvana Westbury, Project Manager, at webmaster@lightsources.org

For news, jobs, events and proposal deadlines, please visit the homepage

Synchrotron light proves effectiveness of several drugs in virus infections like SARS-CoV2

Microtubules are intracellular structures that function as true cellular highways for the transport of substances, vesicles, organelles and even viruses, in the case that a cell gets infected. In most viral infections, they are the transport routes to generate the viral factories, regions close to the nucleus where virus production is concentrated.

The idea is to design drugs that, by binding to microtubules, prevent viruses from using them during the infection process. In general, drugs that target microtubules are called MTAs (microtubule targeting agents). There are two types: stabilizers (MSA) and destabilizers (MDA). Both are widely available and most of these drugs are in the WHO Essential Medicines List, and hence, they are therapeutic alternatives that are affordable and available worldwide.

Researchers from CIB Margarita Salas selected 16 commercially available MTA (including 15 in clinical use) to analyse their capacity to inhibit the viral replication against 5 different virus: the human common cold coronavirus (HCoV), the pandemic SARS-CoV-2 coronavirus, the vesicular stomatitis virus, the poxvirus vaccinia and African swine fever virus.

Scientist confirmed that the MTA tested had an effect on virus replication and spreading and that this effect varies according to the virus dependency on the microtubular network. “The inhibitory effect obtained varied depending on the specific functions that viruses have developed throughout evolution to exploit cellular transport machinery”, explains Dra. Marian Oliva, researcher at CIB Margarita Salas-CSIC.

In particular, the most complex use of microtubules filaments might correspond to coronavirus (CoVs), such as the one responsible for the Covid-19 pandemic. Microtubules are necessary both for virus internalization and later at several levels of the formation of the viral replication site. In fact, S and M coronavirus proteins (located on the virus surface) interact with tubulin (protein that forms microtubules) during the infection, although their specific function is currently unknown. Various projects involving the use of the ALBA Synchrotron are under way to study deeper these aspects.

Read more on the ALBA website

Image: Image obtained at the XALOC beamline of ALBA. Drug mebendazole (MBZ) bounds to the protein that forms the microtubules: tubulin (T2RT and T1D).

How a soil microbe could rev up artificial photosynthesis

Researchers discover that a spot of molecular glue and a timely twist help a bacterial enzyme convert carbon dioxide into carbon compounds 20 times faster than plant enzymes do during photosynthesis. The results stand to accelerate progress toward converting carbon dioxide into a variety of products.

Plants rely on a process called carbon fixation – turning carbon dioxide from the air into carbon-rich biomolecules ­– for their very existence. That’s the whole point of photosynthesis, and a cornerstone of the vast interlocking system that cycles carbon through plants, animals, microbes and the atmosphere to sustain life on Earth. 

But the carbon fixing champs are not plants, but soil bacteria. Some bacterial enzymes carry out a key step in carbon fixation 20 times faster than plant enzymes do, and figuring out how they do this could help scientists develop forms of artificial photosynthesis to convert the greenhouse gas into fuels, fertilizers, antibiotics and other products.

Now a team of researchers from the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University, Max Planck Institute for Terrestrial Microbiology in Germany, DOE’s Joint Genome Institute (JGI) and the University of Concepción in Chile has discovered how a bacterial enzyme – a molecular machine that facilitates chemical reactions – revs up to perform this feat.

Rather than grabbing carbon dioxide molecules and attaching them to biomolecules one at a time, they found, this enzyme consists of pairs of molecules that work in sync, like the hands of a juggler who simultaneously tosses and catches balls, to get the job done faster. One member of each enzyme pair opens wide to catch a set of reaction ingredients while the other closes over its captured ingredients and carries out the carbon-fixing reaction; then, they switch roles in a continual cycle.  

Read more on the SLAC website

What drives rechargeable battery decay?

How quickly a battery electrode decays depends on properties of individual particles in the battery – at first. Later on, the network of particles matters more.

Rechargeable lithium-ion batteries don’t last forever – after enough cycles of charging and recharging, they’ll eventually go kaput, so researchers are constantly looking for ways to squeeze a little more life out of their battery designs.

Now, researchers at the Department of Energy’s SLAC National Accelerator Laboratory and colleagues from Purdue University, Virginia Tech, and the European Synchrotron Radiation Facility have discovered that the factors behind battery decay actually change over time. Early on, decay seems to be driven by the properties of individual electrode particles, but after several dozen charging cycles, it’s how those particles are put together that matters more.

“The fundamental building blocks are these particles that make up the battery electrode, but when you zoom out, these particles interact with each other,” said SLAC scientist Yijin Liu, a researcher at the lab’s Stanford Synchrotron Radiation Lightsource and a senior author on the new paper. Therefore, “if you want to build a better battery, you need to look at how to put the particles together.”

Read more on the SLAC website

Image: A piece of battery cathode after 10 charging cycles. A machine-learning feature detection and quantification algorithm allowed researchers to automatically single out the most severely damaged particles of interest, which are highlighted in the image.

Credit: Courtesy Yijin Liu/SLAC National Accelerator Laboratory

Giorgio Margaritondo’s #My1stLight

Synchrotron Radiation from a Synchrotron

We must face reality: almost all synchrotron radiation users of today have never seen a synchrotron! As we know, what they call “synchrotrons” are really “storage rings”. Only a tiny minority of elderly, retired scientists worked at real synchrotrons – and were lucky to survive the experience. I am one of them. Indeed, the first time I used synchrotron radiation was in the 1970s at the 1.1 GeV “elettrosincrotrone” of the Frascati National Laboratory. Which in the 1970s was the source for our synchrotron radiation project “PULS”.

How was my experience? Miserable! Contrary to a storage ring, a synchrotron is a pulsed source in which electron bunches are continuously injected, accelerated and dumped. The bunches cause very dangerous radiation, so we could not work close to our experimental chamber when they travelled in the ring. This transformed simple operations into a nightmare. For example, a sample alignment that takes a few minutes at a storage ring required days or weeks — subsequent small adjustments being separated by hours of accelerator operation.

At Frascati, we were dreaming of using the excellent storage ring Adone instead of the synchrotron — but this happened only later. Personally, after months of misery I found a way out when I was hired by Bell Labs in New Jersey. Which, to my relief, was as far as possible from the synchrotron facilities of that time. But I could not escape my destiny: shortly after my arrival, Bell Labs asked me to start experiments at the Wisconsin Synchrotron Radiation Center! Fortunately, the source there was not a synchrotron but the storage ring Tantalus. I could thus appreciate the huge advantage over real synchrotrons. I am indeed convinced from experience that, without the arrival of storage rings, synchrotron radiation research would have died at birth.

Giorgio Margaritondo
Faculté des Sciences de Base, Ecole Polytechnique Fédérale de Lausanne
(EPFL), CH-1020 Lausanne, Switzerland

Image: The Frascati electron synchrotron, where my career in synchrotron radiation started and almost
ended

Rich electronic features of a kagome superconductor

The recently discovered layered kagome metals AV3Sb5 (A=K, Rb, Cs) exhibit diverse correlated phenomena, thought to be linked to so-called Van Hove singularities (VHSs) and flat bands in the material. Using a combination of polarization-dependent angle-resolved photoemission spectroscopy (ARPES) and density-functional theory, researchers led by Professor Ming Shi at the Paul Scherrer Institute directly revealed the sublattice properties of 3d-orbital VHSs and flat bands, as well as topologically non-trivial surface states in CsV3Sb5. The research reveals important insights into the material’s electronic structure and provides a basis for understanding correlation phenomena in the metals.

So-called kagome metals, named after the Japanese woven bamboo pattern their structure resembles, feature symmetrical patterns of interlaced, corner-sharing triangles. This unusual lattice geometry and its inherent features lead, in turn, to curious quantum phenomena such as unconventional, or high-temperature, superconductivity.

The potential for devices that might transport electricity without dissipation at room temperature—as well as a thirst for fundamental theoretical understanding—have led researchers to investigate this new class of quantum materials and try to figure out how electrons interact with the kagome lattice to generate such remarkable features.

A recently discovered class of AV3Sb5 kagome metals, where A can be =K, Rb or Cs, was shown, for instance, to feature bulk superconductivity in single crystals at a maximum Tc of 2.5 at ambient pressure. Researchers suspect that this is a case of unconventional superconductivity, driven by some mechanism other than the phonon exchange that characterizes bonding in the electron-phonon coupled superconducting electron-pairs of conventional superconductivity.

This, as well as other exotic properties observed in the metal, are thought to be connected to its multiple “Van Hove singularities” (VHSs) near the Fermi level. VHSs, associated with the density of states (DOS), or set of different states that electrons may occupy at a particular energy level, can enhance correlation effects when a material is close to or reaches this energy level. If the Fermi level lies in the vicinity of a Van Hove point, the singular DOS determines the physical behavior due to the large number of available low-energy states. In particular, interaction effects get amplified not only in the particle-particle, but also in the particle-hole channels, leading to the notion of competing orders.

Read more on the PSI website

Image: Yong Hu, first author, and Nicholas Clark Plumb, who made the experimental station, at the Surface/Interface Spectroscopy (SIS) beamline of the Swiss Light Source (SLS) (L to R)

Credit: Paul Scherrer Institut / Mahir Dzambegovic

The first direct visual observation of synchrotron light in a laboratory

Lightsources.org has created this short video to mark the 75th Anniversary of the first direct visual observation of synchrotron light in a laboratory. It’s release marks the start of our celebrations, which have been made possible thanks to contributions from our member facilities, guest speakers and members from our around the light source community.

Marking the 75th Anniversary of the 1st direct visible observation of synchrotron light in a laboratory

We are hugely grateful to all those who have taken the time to support our activities. On behalf of all the Lightsources.org members, we hope you enjoy our celebrations, which will include:

The creation of a timeline and a collection of achievements from across our 31 member facilities to be shared on the website and social media Our #My1stLight campaign, which invites light source staff and external researchers to send in their memories of first encounters with synchrotron light. Visit our campaign page to find out more

A special online symposium to mark 75 Years of Science with Synchrotron Light on Thursday 28th April – Registration is open here

Seeing more deeply into nanomaterials

New 3D imaging tool reveals engineered and self-assembled nanoparticle lattices with highest resolution yet—7nm—about 1/100,000 of the width of a human hair

From designing new biomaterials to novel photonic devices, new materials built through a process called bottom-up nanofabrication, or self-assembly, are opening up pathways to new technologies with properties tuned at the nanoscale. However, to fully unlock the potential of these new materials, researchers need to “see” into their tiny creations so that they can control the design and fabrication in order to enable the material’s desired properties.

This has been a complex challenge that researchers from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Columbia University have overcome for the first time, imaging the inside of a novel material self-assembled from nanoparticles with seven nanometer resolution, about 1/100,000 of the width of a human hair. In a new paper published on April 7, 2022 in Science, the researchers showcase the power of their new high-resolution x-ray imaging technique to reveal the inner structure of the nanomaterial. 

The team designed the new nanomaterial using DNA as a programmable construction material, which enables them to create novel engineered materials for catalysis, optics, and extreme environments. During the creation process of these materials, the different building blocks made of DNA and nanoparticles shift into place on their own based on a defined “blueprint”—called a template—designed by the researchers. However, to image and exploit these tiny structures with x-rays, they needed to convert them into inorganic materials that could withstand x-rays while providing useful functionality. For the first time, the researchers could see the details, including the imperfections within their newly arranged nanomaterials.

Read more on the BNL website

Image: An artist’s impression of how the researchers used x-ray tomography as a magnifying lens to see into the inner structure of nanomaterials

Record time resolution

RESEARCH TEAM DEMONSTRATES BEST PUMP–PROBE TIME RESOLUTION REPORTED SO FAR AT X-RAY FREE-ELECTRON LASER FACILITIES

After being illuminated with light, the atoms in materials react within femtoseconds, i.e. quadrillionths of a second. To observe these reactions in real time, the experiment setup used to capture them must operate with femtosecond time resolution too, otherwise the resulting images will be “blurred”. In a proof-of-principle experiment at the European XFEL, a research team has demonstrated a record time resolution of around 15 femtoseconds—the best resolution reported so far in a pump–probe experiment at an X-ray free-electron laser (FEL) facility, while keeping a high spectral resolution. “These results open up the possibility of doing time-resolved experiments with unprecedented time resolution, enabling the observation of ultrafast processes in materials that were not accessible before,” explains Daniel Rivas from European XFEL, principal investigator of the experiment and first author of the publication in the scientific journal Optica, in which the team from European XFEL and the DESY research centre in Hamburg report their results.

One of the goals of experiments at the European XFEL is to record “molecular movies”, i.e. series of snapshots of dynamic processes taken in extremely rapid succession, which reveal the details of chemical reactions or physical changes in materials at high time resolution. Understanding the molecular rearrangement during such reactions is an essential step towards controlling processes in our natural environment, such as radiation damage in biological systems or photochemical and catalytic reactions. One technique to create such movies is pump–probe spectroscopy, where an optical laser pulse (the “pump” pulse) excites a certain process in a sample and the X-ray laser pulses (the “probe” pulses) are used to take a series of snapshots in order to observe how the process evolves in time.

Read more on the European XFEL website

Image: An ultrashort X-ray pulse and an optical laser pulse interact simultaneously with a neon atom. The X-ray pulse removes an electron from the inner electronic shell and, due to the electromagnetic field of the optical laser that is present at the moment of ionization, the outcoming electron is modulated in energy.

Credit: illustratoren.de/TobiasWuestefeld in cooperation with European XFEL

X-rays capture ageing process in EV batteries

CLS researcher Toby Bond uses x-rays to help engineer powerful electric vehicle batteries with longer lifetimes. His research, published in The Journal of the Electrochemical Society, shows how the charge/discharge cycles of batteries cause physical damage eventually leading to reduced energy storage. This new work points to a link between cracks that form in the battery material and depletion of vital liquids that carry charge.

Bond uses the BMIT facility at the Canadian Light Source at the University of Saskatchewan to produce detailed CT scans of the inside of batteries. Working with Dr. Jeff Dahn at Dalhousie University, he specializes in batteries for electric vehicles, where the research imperative is to pack in as much energy as possible into a lightweight device.

“A big drawback to packing in more energy is that generally, the more energy you pack in, the faster the battery will degrade,” says Bond.

In lithium-ion batteries, this is because charging physically forces lithium ions between other atoms in the electrode material, pushing them apart. Adding more charge causes more growth in the materials, which shrink back down when the lithium ions leave. Over many cycles of this growing and shrinking, micro-cracks begin to form in the material, slowly reducing its ability to hold a charge.

Read more on the CLS website

Image: Toby Bond adjusts a battery sample on the BMIT beamline

Yonghua Du recognized as a highly cited researcher 2021

Du was cited by Web of Science in its Cross-Field category, which identifies researchers who have contributed to highly cited papers across several different fields

Brookhaven Lab scientist Yonghua Du has been named a highly cited researcher in Web of Science’s 2021 report. Each year, the Web of Science publishes a list of researchers who have demonstrated significant and broad influence in a chosen field or fields over the past decade through highly cited papers. The list includes the top 1 percent of researchers by citation for a chosen field or fields. Du was recognized in the cross-field category.

“I have spent my career at synchrotron facilities, collaborating with as many researchers all over the world to uncover the secrets of their samples using our unique tools. Many excellent papers were published,” said Du. “So, I am proud of this achievement.”

In his position as a beamline scientist at the National Synchrotron Light Source II (NSLS-II), Du balances his time between developing more research capabilities for his beamline and building strong collaborations with researchers from across the globe. These researchers—called users—work together with NSLS-II experts to solve the biggest scientific challenges of today using the facility’s unique research tools.

Read more on the Brookhaven National Lab website

Image: Brookhaven Lab scientist Yonghua Du standing in front of the Tender Energy X-ray Absorption Spectroscopy (TES) beamline at the National Synchrotron Light Source II

Hybrid Ring – Conceptual design of light source that allows simultaneous use of two beams

A new idea for epochal synchrotron radiation facility is proposed at the Photon Factory jointly operated by the Institute of Materials Structure Science and the Accelerator Laboratory of the High Energy Accelerator Research Organization (KEK). The new facility called the Hybrid Ring is the advanced storage ring light source combined with a long pulsed superconducting linear accelerator.

The Photon Factory (PF) was the first dedicated synchrotron radiation facility in Japan with a wide range of photon energy from VSX to X-rays. From its first beam in 1982, PF widely supports both basic science and its application of the researchers from universities, national organizations, and private companies. Now, KEK aims to construct a successor facility to the Photon Factory by the early 2030s that is the 50th anniversary of the first beam. New design for the light source facility suitable for a world-class accelerator research institute is underway.

A research group led by Associate Professor Kentaro Harada and Professor Yukinori Kobayashi at the Accelerator Division 6 of the Accelerator Laboratory and Professor Nobumasa Funamori at the Photon Factory of the Institute of Materials Structure Science have developed a new concept of a synchrotron radiation facility called the Hybrid Ring. The Hybrid Ring can not only promote conventional synchrotron radiation user experiments but also develop a new type of user experiment by simultaneous use of two synchrotron radiation beams. These features are expected to make further contributions to a wider range of scientific and technological fields.

Read more on the KEK website

Image:  Conceptual diagram of the Hybrid Ring

Clearest crystalline form revealed

To capture extraordinary nanoscale details in crystallography takes the powerful coherent flux of a 4th generation light source. Recent work in Light: Science & Applications by an international research team has revealed 3D images of a complex crystalline star structure using Bragg ptychography and new advanced analysis tools at MAX IV’s NanoMAX beamline. The results demonstrate the possibility of unprecedented data quality beyond experimental limitations from new synchrotron sources.

It is the high brilliance of 4th generation synchrotrons which now makes high resolution 3D Bragg ptychography especially valuable for investigation of crystal samples, from biominerals found in teeth, bones, shells and more, to a diversity of technologically relevant materials exhibiting magnetic, ferro-electric, topological properties to cite a few.

“New microscopy tools can provide not only sharper images but allow completely new ways of studying extremely complex materials, improving our understanding of the world around,” said Dina Carbone, MAX IV Scientist and study author. “This is the first step to produce technologies that truly responds to our needs in an efficient and sustainable way.”

The current study succeeded in producing a 3D image of the silicon crystalline sample with internal atomic deformations. The star is a well-known structure, chosen to assess the capabilities of the new diffraction end-station of NanoMAX previously designed by Carbone. The research team involved pioneered the 3D Bragg ptychography technique in 2011, and continues with its development.

Read more on the MAX IV website

Image: (left) 3D volume rendering (iso-surface) of crystalline Si-star with Bragg-ptychography, (center), atomic displacement along the z direction. The color map shows strain (dimensionless) (right) SEM image of the same Si-star sample, for comparison. 

Credit: Dina Carbone

Synchrotron light for faster and more effective tooth whitening treatments

A recent work of the Universitat Autònoma de Barcelona (UAB) in collaboration with the ALBA Synchrotron, has studied the side effects of typical tooth whitening treatments, based on oxidation, compared to a new treatment developed by the authors through reduction. Results showed the whitening effect of the novel treatment to be highly improved in terms of application time needed, efficiency and safety, which makes it a promising candidate to develop novel whitening treatments. Experiments at the MIRAS beamline of ALBA helped to determine the chemical mineral modifications in the dental enamel.

Tooth whitening is a common aesthetic treatment around the world. To obtain better results, higher concentrations of oxidizing agents and longer application times are needed, but this may increase side effects like hypersensitivity and pulp damage, tooth demineralization and gingival irritation. Besides, the need to apply these products for hours is not very comfortable for the user.

Typical tooth whitening treatments are based on the oxidizing power of hydrogen peroxide, which breaks the double bonds of the staining molecules on the teeth’s surface making them unable to absorb light. This way the molecule becomes transparent, thus obtaining a bright, clean and white smile.

In a recent work of the Research Group of Separation Techniques in Chemistry (GTS) from the Universitat Autònoma de Barcelona (UAB) in collaboration with the ALBA Synchrotron, researchers have used bovine incisors as in vitro model to study the side effects of whitening treatments. They compared typical whitening treatments (based on oxidation with carbamide peroxide) to new treatment developed and patented by the authors through reduction via metabisulfite, which also makes the staining molecules colorless. However, metabisulfite presents a faster whitening effect, which permits the use of lower concentrations and shorter application times. Results showed how the whitening effect of the novel treatment is highly improved in terms of application time needed, with the consequent reduction of side effects. This makes it a promising candidate to develop novel whitening treatments.

Read more on the ALBA website

Image: Dental smile

Credit: jannoon028 – www.freepik.es

Discovered: An easier way to create “Flexible Diamonds”

As hard as diamond and as flexible as plastic, highly sought-after diamond nanothreads would be poised to revolutionize our world—if they weren’t so difficult to make. A team of scientists led by Samuel Dunning and Timothy Strobel of the Carnegie Institution for Science using high-brightness x-rays from the U.S. Department of Energy’s (DOE’s) Advanced Photon Source developed an original technique that predicts and guides the ordered creation of strong, yet flexible, diamond nanothreads, surmounting several existing challenges.  The innovation will make it easier for scientists to synthesize the nanothreads—an important step toward applying the material to practical problems in the future. The work was published in the Journal of the American Chemical Society.

Diamond nanothreads are ultra-thin, one-dimensional carbon chains, tens of thousands of times thinner than a human hair. They are often created by compressing smaller carbon-based rings together to form the same type of bond that makes diamonds the hardest mineral on our planet. However, instead of the three-dimensional carbon lattice found in a normal diamond, the edges of these threads are “capped” with carbon-hydrogen bonds, which make the whole structure flexible.

Dunning explains: “Because the nanothreads only have these bonds in one direction, they can bend and flex in ways that normal diamonds can’t.”

Scientists predict that the unique properties of carbon nanothreads will have a range of useful applications from providing sci-fi-like scaffolding on space elevators to creating ultra-strong fabrics. However, scientists have had a hard time creating enough nanothread material to actually test their proposed superpowers.

Read more on the APS website

Image: The starting sample of pyridazine—a six atom ring made up of four carbons and two nitrogens—changes under pressure as diamond nanothread formation progresses. The first and last images show that there has been a permanent color change between the samples after thread formation. The images don’t show individual threads, but “bulk” samples of pyridazine during compression, each around 40 microns thick with a 180-micron diameter.

Credit: Samuel Dunning

Structural studies of SARS-CoV-2 nucleocapsid protein

Perspectives in relation to diagnosis and drug design

 A novel zoonotic coronavirus SARS-CoV-2 was originally explored in Wuhan, China in December 2019 and further regarded to the serious pandemic known as COVID-19. In early March 2022, the global COVID-19 pandemic has caused over 453 million confirmed cases and over 6 million deaths (John Hopkins Coronavirus Resource Center, https://coronavirus.jhu.edu).

 The COVID-19 virus and the emergence of new virus variants seriously threat to global public health. It is a strong requirement to develop the effective diagnostic tools which are able to quickly and reliably detect active SARS-CoV-2 infections.

 Structural proteins of the COVID-19 virus are very important to understand its pathogenic mechanism, thus leading to the development of antibodies, vaccines and drugs for targeting these proteins and viruses.

 SARS-CoV-2 comprised the four structural proteins; the spike (S), nucleocapsid (N), envelope (E) proteins and membrane glycoprotein (M). A complete virus particle (virion) is represented in Figure 1. Cryo-electron microscopy is one of the powerful tools to determine the overall structure of the S protein, thus presenting a unique crown or ‘corona’-like shape.

 Three viral proteins; the spike (S), envelope (E) and membrane (M) are embedded in the outer layer of the corona viral particle. The corona viruses protect themselves from the surrounding environment, then the ribonucleic acid (RNA) forms a stable packed in the lipid membrane. The nucleocapsid protein (nucleoprotein) is responsible for tightly wrap the RNA of viruses. However, the fatty membrane of SARS-CoV-2 is sensible to be destroyed by soap, detergent or surfactant.

 The nucleocapsid protein significantly involves in viral genomic RNA binding, thus protecting the coiled RNA as its genetic material inside the virus particle. Moreover, the N protein also plays an important role in the early stages of viral infection when the RNA genome is first released into the target host cell.

 X-ray crystal structures of the N-terminal (PDB entry 7CDZ) and C-terminal domains have been illustrated here (PDB entry 6WZO). Holo structure of N-terminal domain in complex with double strand RNA (PDB entry 7ACS) has been determined by Nuclear Magnetic Resonance Spectroscopy technique.

Read more on the Thai Synchrotron website

Image:  Three dimensional models of the SARS-CoV-2 virion and a schematic diagram of its four structural proteins. 

Credit: Figures were modified from coronavirusexplained