Superbugs Seem To Have Been Around Even 450 Million Years Ago

Scientists found that the enterococci’s ancestors may date back to almost 450 million years ago.

One of the most dangerous strains of so-called “superbugs”, enterococci, has been found to have ancestors as far back as almost 450 million years ago. That is about the time when the first animals came crawling up out of the ocean. These bacteria likely lived in the guts of those early land-pioneers, and some of our most challenging infections of the future are descended from them.

At 450 Million Years, Superbugs are Older than Dinosaurs

A new study by researchers at both MIT and Harvard detail the findings. Published in the online journal, Cell, it explains that since the dawn of animal life, bacteria and animals have existed in a tenuous love/hate relationship.

“By analyzing the genomes and behaviors of today’s enterococci, we were able to rewind the clock back to their earliest existence and piece together a picture of how these organisms were shaped into what they are today,” said Ashlee M. Earl.

She is a Ph.D., co-corresponding author and group leader for the Bacterial Genomics Group at the Broad Institute of MIT and Harvard.

First, the bacteria evolved alone. Then, 542 million years ago during what is known as the Cambrian Explosion, multicellular animals appeared on the scene. That is when bacteria began to co-exist with the animals in one of three ways.

They either worked as symbiotes, helping the animals break down resources like our gut bacteria. Or they simply existed without interacting. They may have been floating around in the same environment, maybe even serving as food sources. Or they became deadly, causing breakdowns in the animals’ cells or organ systems. In other words, diseases.

The team of scientists determined that the enterococci evolved with the animals when they emerged on land about 450 million years ago. They found a way of surviving drying out when they were expelled. This made them transmissible to other land species with were not adapted to these different bugs. Most likely, according to the study, our modern “superbugs” have descended from them.

Antibiotic resistant strains of various germs are starting to appear in hospitals worldwide. This has created a fear that research may not keep up with evolution. Looking at the earliest forms of these bacteria may provide keys to defeating them today.

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