MAY 04, 2021 12:05 AM PDT

A Potential Weakness in SARS-CoV-2 is Caught on Video

WRITTEN BY: Carmen Leitch

Viruses like SARS-CoV-2 have to get into host cells in order to cause an infection, and they do so by using their spike protein to bind to proteins on host cell surfaces. The spike protein of SARS-CoV-2 has been a target of much research, and we know that it can bind to several receptors including one called ACE2. Other molecules can bind to the viral spike protein too, like neutralizing antibodies that prevent the virus from causing infection. New work has demonstrated that proteins called lectins can also bind to the SARS-CoV-2 spike protein. This research, which has not yet been peer-reviewed but is available on bioRxiv, also captured that binding on video.

"Lectins are proteins that can bind the sugar molecule structure on lipids or proteins such as the spike protein," explained Dr. Josef Penninger, director of the Life Sciences Institute in Vancouver. "Our idea is to harness this property to develop a drug to combat COVID-19 disease."

Researchers have been searching for molecules that can bind to the SARS-CoV-2 spike protein. Penninger's team created a lectin library, and used it to find two lectins that are good at binding to sugars called glycans on the SARS-CoV-2 spike protein. Glycans can help disguise spike proteins, helping them to prevent detection by the immune system. Another approach is taken by the drug candidate APN01, which mimics ACE2 receptors; they are meant to compete with the receptors to bind to the virus, so the virus, in theory, would bind to APN01 instead of host cells.  

"We are working with lectins on the same principle," said Penninger. "But the lectins would occupy neuralgic sites directly on the spike protein and thus disrupt the pathogen's binding to the cells. The door is blocked because the key is gummed up with lectins."

"We have now tools at hand that can bind the virus's protective layer and thereby block the virus from entering cells," said a co-first study author Dr. Stefan Mereiter. "Moreover, these glycan sites are highly conserved among all circulating SARS-CoV-2 variants, so this could be its Achilles' heel."

Transmission electron micrograph of SARS-CoV-2 virus particles (UK B.1.1.7 variant), isolated from a patient sample and cultivated in cell culture. Image captured at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. Credit: NIAID

Study collaborator Dr. Peter Hinterdorfer and colleagues at the University of Linz measured the number of bonds and binding forces between the lectins and spike protein.

"We also filmed this bond," noted Dr. Hinterdorfer. "What is spectacular about the video is that you can see the dynamics of the spike protein."

The researchers were surprised by all the mobility in the spike protein.

"We saw that it actually opens up on the surfaces, and that the three arms are dynamic," said Hinterdorfer. "The lectins, on the other hand, were able to attach themselves to the structure for a long time on a biological scale."

Sources: Phys.org via University of British Columbia, bioRxiv

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAR 31, 2021
Microbiology
Deep-Sea Microbes Are 'Invisible' to the Human Immune System
MAR 31, 2021
Deep-Sea Microbes Are 'Invisible' to the Human Immune System
Scientists took an exploratory journey to a place in the central Pacific Ocean in Kirbati called the Phoenix Islands Pro ...
APR 07, 2021
Plants & Animals
Scientists Discover a Crab-Dissolving Parasite
APR 07, 2021
Scientists Discover a Crab-Dissolving Parasite
Parasites abound throughout the natural world. While not all of them cause the host's death, this newly discovered p ...
APR 19, 2021
Genetics & Genomics
Announcing ISHI 32: Attend In Person or Virtually!
APR 19, 2021
Announcing ISHI 32: Attend In Person or Virtually!
The 32nd International Symposium on Human Identification (ISHI 32) will be held this September at Disney’s Coronad ...
APR 25, 2021
Cell & Molecular Biology
Natural Molecules Can Stop Antibodies From Neutralizing SARS-CoV-2
APR 25, 2021
Natural Molecules Can Stop Antibodies From Neutralizing SARS-CoV-2
When we're exposed to a pathogen, our immune system normally mounts a robust response against it. Antibodies are generat ...
APR 28, 2021
Cell & Molecular Biology
Learning More About the Sugars That Mediate Immune Interactions
APR 28, 2021
Learning More About the Sugars That Mediate Immune Interactions
Sugar is something sweet to add to your food, but just like fat, different types of sugars play important roles in biolo ...
MAY 09, 2021
Genetics & Genomics
Another Neurodevelopmental Disorder is Discovered
MAY 09, 2021
Another Neurodevelopmental Disorder is Discovered
Researchers are identifying more rare disorders because of advances in genetic sequencing technologies, which have made ...
Loading Comments...