CRISPR is the acronym for "clustered regularly interspaced palindromic repeats."
CRISPR is a discreetly organized system. It serves as the storage bank of representative sequence information from assorted types of bacterial-invading viruses called “bacterial phage(s)” or simply “phage(s).”
The “repeats” represent molecular hedges, while the “spacers” contain phage sequences deposited between the molecular hedges. Each spacer denotes a prior phage invasion from which the host bacterium snatches a phage slice and storages it in CRISPR for future usage. Then, the next time the same phage invader shows up, the bacterium can quickly retrieve information stored in CRISPR and mount a quick immune response to eliminate the invading phage.
In a way, CRISPR resembles immune memory in humans.
The structure and mechanism of CRISPR's actions and how CRISPR, from nature, has been modified as a highly effective gene editing tool in clinics and laboratories will be discussed in subsequent content topics.
Point to Ponder: Bacteria have evolved to rely on CRISPR—to literally chop up invading phage genomes using “cutting enzymes,” officially known as endonucleases. How do bacteria prevent the same destruction enzymes from damaging bacteria’s own (self) genome? The answer will be presented in the next topic.
