Here’s one for Hollywood.  Scientists in a special secure facility recreate a bacteria so deadly that it wiped out 25 million people throughout Europe in the 1300’s so they can better understand why the bacteria was so deadly.  How does it work out? Let your imagination go from there.

It is true.  Scientists have recently reconstructed the DNA of the bacterium, Yersinia pestis; the same bacteria believed to be the cause of the bubonic plague or the “Black Death” outbreak that wiped out nearly half of the European population in the mid 1300’s.  Scientists used teeth from four such victims buried near the Tower of London in a cemetary that had been created specifically for the arrival of the plague.  By utilizing a known technique wherby complementary DNA strands bind together, scientists were able to use a modern version of Yersinia pestis bacteria to separate the medieval version from the teeth.

Yes, the bacteria that caused the plague still exists today and the last known outbreak happened in Madagascar in the 1990’s although the sickness presents different symptoms today.   The modern version of the bacteria is susceptible to antibiotics just as the medieval version.  Unfortunately for most of Europe and the rest of the world in the 1300’s, antibiotics were not discovered yet.  Both versions of the bacteria have only 1 chromosome and is about 4.6 million DNA units long.  Scientists further discovered that in the 660+ years since the horror, the modern version has only 97 mutations from the medieval strain.  These changes will further be studied one by one to determine how each change affects the micobe’s virulence.

So, if the bacteria exists today, what makes the bacteria less virulent?  Scientists are still debating this issue but it is known that the modern version of the plague bacterium often rearranges the order of its genes, which could affect pathogenicity.  Other thoughts are as simple as that we don’t live in the medieval world today.  During the 1300’s in Europe, the climate was cooling, crops were rotting due to rains and famines, sanitation was poor, people were malnourished and the Hundred Years War had just begun when the disease first struck.

Scientist’s now hope to one day be able to modify a modern Yersinis pestis bacterium so that it’s genome exactly matches that of the medieval version.  What could possibly go wrong?