MIT scientists discover a new antiviral defense system in bacteria | MIT News


The next press release was launched right now by the Broad Institute of MIT and Harvard.

Microorganisms use a wide range of protective methods to combat viral infection, and a few of these methods have led to groundbreaking applied science corresponding to CRISPR-based gene enhancement. Scientists believe there are many other antiviral weapons to be discovered in the microbial world.

A team led by researchers from the MIT Broad Institute and Harvard, and MIT’s McGovern Mind Analysis Institute, has discovered and qualified one of these undiscovered methods of microbial protection. They found that certain proteins in microorganisms and archaea (collectively known as prokaryotes) sense viruses in surprisingly straightforward ways, recognizing key parts of the virus and causing single-celled organisms to commit suicide to suppress a virus infection. within a microbial group. The study marks the first time this mechanism has been observed in prokaryotes, and organisms from all three domains of life – microorganisms, archaea and eukaryotes (including vegetation and animals) – use sample recognition of conserved viral proteins to defend against pathogens.

The job seems to be like this: Science.

“This study demonstrates exceptional unity in how sample recognition occurs in very different organisms,” said lead writer Feng Zhang, a senior fellow of the institute at Broad, and James and Patricia Poitras Professor of Neuroscience. at MIT. He is a cognitive science and organic engineering researcher at MIT and the McGovern Institute of MIT and the Howard Hughes Medical Institute. “It was very exciting to combine approaches from genetics, bioinformatics, biochemistry and structural biology in a single study to learn about this fascinating molecular system.”

Microbial arsenal

In an earlier study, researchers combed through DNA sequence information from hundreds of microorganisms and archaea, revealing several thousand genes harboring signatures of microbial protection. In the new study, they were on a handful of these enzyme-coding genes, which are part of the STAND ATPase family of proteins involved in the innate immune response in eukaryotes.

In humans and vegetation, STAND ATPase proteins fight infection by recognizing patterns in a pathogen itself or in the cell’s response to infection. In the new study, the researchers wanted to know if the proteins work the same way in prokaryotes to defend against an infection. The team chose a number of STAND ATPase genes from previous work, delivered them to bacterial cells, and challenged those cells with bacteriophage viruses. The cells took a dramatic defensive response and survived.

The scientists then wondered which part of the bacteriophage triggered this response, so they delivered the viral genes to the microorganism one after another. Two viral proteins triggered an immune response: the portal, which is part of the virus’s capsid envelope containing viral DNA; and terminase, the molecular motor that helps the virus assemble by pushing viral DNA into the capsid. Each of these viral proteins activated a distinct STAND ATPase to protect the cell.


About Author

Comments are closed.