Researchers have reported the discovery of a mechanism that involves bacteria using the CRISPR-Cas adaptive immunity system to fight viruses and foreign invaders of the DNA.
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeat) facilitates specific changes in the DNA of humans, animals and plants and modifies DNA in a faster and easier manner compared with earlier DNA-modifying techniques.
CRISPR is a critical component of the immune systems of bacteria and microorganism with the immune system being responsible for the protection of the health and well-being of the organism.
Bacterial cell can also get invaded by viruses, which are small infectious agents. If a viral infection proses threats to a bacterial cell, the CRISPR immune system is able to thwart the attack by destroying the invading virus' genome, which includes genetic material critical for the continued replication of the virus. The CRISPR immune system therefore provides protection to the bacteria from ongoing viral infection.
Researchers from New Zealand and Netherlands reported that the system gets samples of the genetic material and then stores this in a memory bank so it can easily recognize exposures that may occur in the future and neutralize the attack. The system is capable of storing up to 600 samples and passes these memories to succeeding generations of bacteria.
The role of the system in providing immunity is a relatively new discovery. The CRISPR-Cas comes up with a genetic memory of certain infections that occurred in the past and were caused by viruses and plasmids albeit the system is believed to have Achilles heel given that the invaders that already acquired many mutations may no longer be recognized because the stored samples no longer match closely enough.
Drug developers and researchers from pharmaceutical giants anticipate that gene editing tools such as the CRISPR can lead to the development of new drug or cures for patients with genetic disorders. In a study involving adult mice, researchers were able to demonstrate a cure for a liver disease by replacing the mutant form of the gene with the correct sequence.
CRISPR has potentials in the field of infectious disease by providing a way to develop specific antibiotics that only target the bacterial strains responsible for a disease and sparing the beneficial bacteria. The technology also has its application in the lab for making precise changes in the genetic make-up of organisms. It also has potential applications in industrial processes that involve bacterial cultures.
Photo: Stuart Caie | Flickr
