by Gidon Schwartz, Education & Outreach Executive
Regularly in my role as Outreach and Education Executive at Jnetics, one of the most common points I explain when presenting to people is, “what is DNA?”, and I always explain it the same way:
“DNA is the blueprint of all life. It is found inside the nucleus of (almost) all of your 30 trillion cells. It is a long molecule made up of chemicals or bases represented by the letters A, T, G and C, and when I say long – it is approximately 3 billion letters long. It is contained in the famous double helix structure and carries all the instructions for your body to carry out all of its functions.”
All of these facts almost seem self-evident to me (albeit as someone that studied genetics). What I often overlook is that, not particularly long ago, these things were not known. The scientific world was racing to find the answers to these questions. One of these racers was the man that discovered the four bases of DNA, Phoebus Levene.
Phoebus Levene was born into a Litvak Jewish family as Fishel in Sagar, Russia (now Žagarė, Lithuania) in 1869. Two years later, the Levene family moved to St Petersburg where Phoebus was educated. Despite a sizable Jewish community in St Petersburg, which was amongst the most assimilated Jewish community in the Russian empire, he was one of only a few Jewish students to be allowed to study in his class. This may have imbued him with a love of education, as a theme of his career was that he truly valued educating the next generation of scientists.
After graduating, Levene started medical school at the Imperial Military Medical Academy. This was during a time of rising antisemitism in Russia, so in 1891 Phoebus’ family took the decision to leave Europe and start a new life for themselves in New York. Phoebus, however, being the studious man he was, had a desire to complete his training. After ensuring his parents were settled in the New World, Phoebus returned to his native land to complete his studies before emigrating himself in 1892.
Unfortunately, early on in his post-medical research career at Columbia, Phoebus fell incredibly ill with tuberculosis and spent two years recovering in Switzerland. During this time, he developed lifelong friends that he continued to visit throughout his life. Upon his recuperation in Switzerland, he had a great turning point in his life and in the whole biochemical field. He visited many labs across the world from New York to Munich and whilst as a visiting worker in Marburg, he began to work on nucleic acids – a field he delved further into for much of his career.
His biggest early breakthrough was not one of science, but of logic. To truly be at the forefront of science and medicine, one needs the facilities to match their mind and their ambitions. At the time, many labs, especially in Europe, were woefully ill equipped and had poor management structures, such as top-down directives relating to administrative processes, preventing the academics from doing their best work. Fortunately for Phoebus, the Rockefeller Institute was founded around this time. He joined the lab as the lead of its biochemical lab; this is where he made his most ground-breaking discoveries.
To effectively explain this breakthrough, we need to consider the building blocks of DNA. It is made of a sugar phosphate backbone with nitrogenous bases (i.e., a sugar molecule connected to a phosphate molecule, connected to a base with a nitrogen in it.) These molecules join up to create the DNA, with all of its quirks, that make you, you! It was Phoebus Levene, in 1909, who discovered that these were the fundamental building blocks of DNA. Not only did he discover the structure, but he coined the term nucleotide – a term used in classrooms throughout the world to this day. He also identified all four different bases that make up DNA (A, C, G and T) in order to code for everything your body needs to survive.
Nevertheless, even great scientists get things wrong. And one of the big questions of the day was how these bases interact and form the actual structure of DNA. This was eventually cracked by Watson and Crick in 1953. Levene’s theory was that all four bases were connected to a central backbone with all the bases in equal proportion; this discovery was eventually proved wrong by Erwin Chargaff, and to find out more about him tune in for tomorrow’s blog!
When a researcher comes toward the end of their illustrious career, especially after such ground-breaking discoveries as Levene, they often slow down and teach less, however Phoebus was an exception. Throughout his career he published over 700 papers, and every day would take time out of his busy schedule to help younger researchers with their work.
Levene had one other passion – art, especially that of the cubists and ultra modernists. The walls of his house were plastered with paintings and other pieces of art which Levene himself had personally selected.
Levene passed away in 1940, just 13 years before the true significance of his discoveries truly came to light.
