A molecule to help virus in antibodies evasion
- Posted By
Science & Technology
24th Apr, 2021
A new study found that a natural molecule can block the binding of a subset of human antibodies to SARS-CoV-2.
About the key finding
- Instruments: The cryo-Em and X-ray crystallography is used to study.
- Key molecules: It is found that biliverdin and bilirubin can suppress the binding of antibodies to the coronavirusspike protein.
- The researchers discovered that biliverdin binds with the spike protein of SARS-COV-2.
- It gives it an unusual green colouration.
- The same natural molecule reduced antibody binding to the spike.
- Functioning: When SARS-CoV-2 infects a patient’s lungs it damages blood vessels and causes a rise in the number immune cells.
- This increases the levels of biliverdin and bilirubin in the surrounding tissues.
- The presence of these molecules gives virus more opportunity to hide from certain antibodies.
- The biliverdin attaches to the spike N-terminal domain and stabilises it. This causes the spike to not to open up and to expose parts of its structure.
- As a result some antibodies are not able to access their target sites and cannot bind to and neutralise the virus.
- Significance of study: The discovery could help in explaining that why some Covid-19patients can become severely ill despite having high levels of antibodies against the virus.
- Bilirubin is a yellowish substance in blood.
- It forms after red blood cells break down.
- It then travels through the liver, gallbladder, and digestive tract before being excreted.
- Bilirubin level is found in between 0.3 and 1.2 milligrams per deciliter (mg/dL).
- Biliverdin is a green tetrapyrrolic bile pigment.
- It is a product of heme catabolism.
- It is the pigment responsible for a greenish color which is sometimes seen in bruises.
- Biliverdin has been found in excess in the blood of humans suffering from hepatic diseases.