A Bacterial Declaration of Independence, and the Nasty Fourth of July Disease

The microbes that mark Independence Day

A few years back a survey revealed that a disconcerting 14% of teenagers thought that today, the Fourth of July, is when the United States commemorates its independence—from France.

Sacre bleu.

Nope, of course it was 240 years ago today that the original thirteen American colonies considered themselves to be a new nation, no longer part of the British Empire.

A kind of Amerexit, if you like.

For most of the US, the Fourth of July is a holiday, but this doesn’t mean a day off from the uBiome newsletter. Oh no.

And of course, just as you might expect, we’ve spared no effort to scour the world of microbiology for bacterial connections to Independence Day, which are surprisingly abundant.

So let’s begin at the Chinese University of Hong Kong, where a team of researchers in 2010 demonstrated the idea of using bacteria to store data.

They did this by recording the 8,074 characters of the Declaration of Independence into just 18 cells of bacteria.

Their process started by turning the text into a string of quaternary digits, quaternary being the base-4 numeral system.

Just as the binary system represents any number with ones and zeros, the quaternary system does so with zeros, ones, twos, and threes.

This string of digits was then transformed by replacing numerals with the letters G, A, C, and T—and encoded into a DNA sequence.

The researchers estimated that a single gram of bacteria could be used to store 90 GB of information.

And in those days that was Big Data and also, you might say, Bug Data.

From Hong Kong, we head closer to home, but further back in time.

In the late 1970s, Roy Curtiss (now a Professor of Genomics, Evolution and Bioinformatics at the University of Florida) received the first US patent issued for a genetically modified (micro)organism: E. coli x1776, named in honor of the bicentennial anniversary of the founding of the United States of America.

E. coli x1776, a variant of the standard lab bacteria E. coli K-12, was engineered to be relatively harmless but unable to survive outside of the laboratory environment, back in the early days of genetic modification when there was quite legitimate concern about engineered cells “escaping” from research facilities.

So it was 1976 in which the US celebrated the bicentennial, and there’s actually yet another microbial link to the Fourth of July in that year.

A disturbing one, at that.

Over 2,000 members of the Pennsylvania American Legion gathered at a hotel in Philadelphia in 1976 to commemorate that year’s bicentennial.

However, the CDC was subsequently alerted to the deaths of four attending veterans who had died from suspected pneumonia, the beginning of an unfortunate epidemic in which 182 members of the Legion were diagnosed, and 29 fatalities were reported.

Investigators soon realized that the sickness was the result of a new infectious disease, which six months later was identified as being caused by a bacterium that had thrived and multiplied in the hotel’s air-conditioning system.

In recognition of those who had first succumbed to it, the perpetrator was named Legionella pneumophila, and the condition was forever to be known as Legionnaires’ disease.

Who knew there was a Fourth of July connection, though?

Finally, of course this is a holiday with many traditions: parades, fireworks, barbecues.

And the annual reminder from the US Department of Agriculture is to avoid bacterial infections on this day of celebrations by taking extra care with food hygiene.

Now I appreciate that this weekly newsletter is distributed pretty widely around the world (and thank you so much for reading it) but many in the USA will indeed see high temperatures today and may be eating al fresco, which makes it all the more important to avoid letting cold food get too warm, or hot food get too cool.

So please be safe—not sorry—and wherever you are, have a wonderful Fourth of July.

That goes for you and yours.

And your bacteria.


Further reading

Chinese university manages to store data in bacteria

E. coli x1776

Legions of water-borne bacterial diseases

Massively parallel bacterial data storage

USDA Reminds Americans to Avoid Foodborne Bacteria on the Fourth of July