13 Tattooed Tears: CRISPR region of S. thermophilus

A teardrop tattoo beneath the eye has symbolic, often context dependent meaning. One of which, a trophy signifying that the wearer has killed another human; the number of tears represents the number of victims. I think the CRISPR region, now famous for its power in gene editing and talk of designer babies, is the microbial analog of the infamous war trophy: tattooed tears.

Tattoo Tears (Prison Context)

Tattoo Tears (Prison Context)

Next to protists, viruses are a bacteria's worst nightmare. Viruses that only attack and infect bacteria, bacteriophages, are estimated to knock out > 40% of bacteria in the ocean.  Clustered Regularly Inter-spaced Short Palindromic Repeats (CRISPR) is a segment of bacterial* DNA that provides them some immunity against viral attacks. How does it work?

When bacteria is attacked a virus, the bacteria is usually destroyed. However, those that survive the attack keep a piece of the defeated virus (Trophy) in its genome just in case it encountered that virus again; It would know how to defeat it again, like a vaccine.

In the genome of most bacteria you will find an area for war Trophy storage called the CRISPR region. There are 13 war trophies in S. thermophilus' CRISPR region.

Electron micrograph of S. Thermophilus colony

Electron micrograph of S. Thermophilus colony

*CRISPRs have also been observed in archaea.

https://www.nature.com/scitable/definition/bacteriophage-phage-293

https://www.nature.com/scitable/definition/bacteriophage-phage-293