Bacteriophages

Why in news?

• Scientists are exploring the potential of bacteriophages to treat bacterial infections that are resistant to antibiotics.

About Bacteriophages:

• A bacteriophage or phage is a virus that infects bacteria.
• They were discovered independently by Frederick W. Twort in Great Britain (1915) and Félix d’Hérelle in France (1917).
• D’Hérelle coined the term bacteriophage, meaning “bacteria eater,” to describe the agent’s bactericidal ability.

How do Bacteriophages kill bacteria?

• Bacteriophages are harmless to human cells as they do not recognize them as their bacterial prey.
• They work by hunting down bacteria and attaching themselves to the surface of a bacterial cell, before injecting viral DNA material into the cell.
• The viral DNA then replicates inside the bacteria, sometimes by borrowing the DNA replication hardware of the bacteria.
• Once all the bacteria are lysed (dead), they’ll stop multiplying. Like other viruses, phages can lay dormant (in hibernation) until more bacteria show up.

About Phage Therapy:

• Phage therapy is the therapeutic use of bacteriophages for the treatment of bacterial infections.
  • It has reduced side effects and reduced risk of the bacteria developing resistance, since bacteriophages are much more specific than antibiotics.
  • They are typically harmless not only to the host organism but also to other beneficial bacteria such as the gut microbiota, reducing the chances of opportunistic infections.
• Disadvantages of Phage Therapy: 
  • Difficulty of finding an effective phage for a particular infection; a phage will kill a bacterium only if it matches the specific strain.

PRACTICE QUESTION:

Bacteriophage, recently seen in news, are:

(a) Viruses that infect and kill specific bacteria

(b) Bacterium that eats and digests plastic

(c) Viruses that help prevent intestinal inflammation and enhance gut health

(d) Bacterium with ability to biodegrade oil

Answer