GS-3 Science and Technology
GS-2 Issues relating to health
GS-4 Medical Ethics
IISER has determined the atomic structure of McrBC- a complex bacterial protein that helps prevent viral infections in bacterial cells as molecular scissors.
Working with molecular scissors. A high- resolution structure of McrBC was possible by using electron cryomicroscopy, commonly known as cryo-EM.
- The determination of the McrBC’s structure has long-term implications in ‘phage therapy’ and could help combat drug-resistant infections in the future.
- The practice of phage therapy uses bacterial viruses (phages) to treat bacterial infections.
- Phages are groups of viruses that infect and kill bacterial cells and phage therapy is the therapeutic use of bacteriophages to treat bacterial infections.
- Understanding of the molecular scissors would aid in combating multidrug-resistant microbes.
How the molecular scissors in bacteria work?
- Like humans, bacteria to have an elaborate defense system to combat phages or the viruses which infect bacterial cells.
- These phages inject their DNA into the bacterial cell, wherein they multiply and duplicate the virus that eventually bursts out of that cell to infect many more.
- So to prevent infection, bacteria have specialized ‘molecular scissors’ which specifically cut the foreign DNA, thereby preventing their multiplication in bacterial cells.
- The molecular scissors of bacteria also regulate the entry of other foreign DNA that might host an antibiotic resistance gene.
Features of McrBC
- To cut the foreign DNA, McrBC is powered by an inbuilt motor that uses GTP (guanosine triphosphate) is the energy currency of the bacterial cell.
- The atomic structure of McrBC (by using cryo-EM) reveals the details of its working parts. McrBC is used as a laboratory tool to study the readability of human and other genomes.