Phosphorus is still king (The arsenic bacteria saga)

The results are in. No arsenate backbone in bacterial DNA.  The much awaited paper comes from Rosie Redfield's group who has devoted their time and resources to refute the original Science paper by Felisa Wolfe-Simon's group on arsenic bacteria "A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus." Why expend so much energy to refute someone else's work?  Well, the original paper's claim essentially suggests that our society needs to expand our notions of what forms life can take since there may be more than sugar-phosphate backbone DNA out there. That's a big enough impetus if you ask me. I'm not saying that it couldn't be true, but precaution should be taken when you make world-changing claims. You better be sure - it's a part of doing responsible and respectable science - and you should be able to stand by your work after the media frenzy dies down and the critics emerge. Just to give you a brief background, the headlines blew up over this "arsenic bacteria" paper speculating that this is the building blocks of extraterrestrial life.  As an example, Alien: "Did NASA Discover Life on One of Saturn's Moons?" The answer, of course, is NO, since the original authors got their samples from the arsenic-laced waters of Mono Lake in California, not from outer space. The rebuttal paper will also be published in Science - surprise! surprise! - and is already available at Arxiv.  But I doubt that it will grab the front pages as the original paper did. How will the Wolfe-Simon's group respond? Dun-dun-dun. This story, from claim of new discovery to the rebuttal, is what makes Science so interesting! Democracy here is exemplified at its best, so the original authors are free to respond and deliver new proof. I'll keep my eyes peeled for the next Science manuscript and headlines, and maybe also on Retraction watch, but my gut feeling is that all this whole hullabaloo will die with a whimper.

Rosalind's DNA

April 25, 2012. I was reading scientific articles in my office – it’s part of my day job - when I came across a citation for the very first publication correctly identifying the structure of deoxyribonucleic acid, better known as DNA. As you may know, this discovery has helped scientists understand how genetic information is passed on from parents to their children. For all the biochemistry work that I have done, I must confess that I've never read this original masterpiece. Thanks to technology, a few seconds later and voila! "Molecular structure of nucleic acids" is on my screen, despite it being originally published on . . .  April 25, 1953! Eerie coincidence? If that coincidence were the most significant thing that happened to me this day, it would have been sufficient.

Copyright (c) Henry Grant Archive/Museum of London

But no, reading that paper on its 59^th anniversary of its publication brought me back to my college years when I fought tooth and nail to get that A+ in Biochem. One bottom line lesson for my exam was this: James Watson and Francis Crick uncovered the elusive structure of DNA in the most crucial scientific race of the 20^th century. By being the first to correctly identify DNA’s structure, beating out Linus Pauling, unarguably the most influential chemist at the time, Watson, Crick, and their lesser-known colleague, Maurice Wilkin were deservingly awarded the Nobel Prize in Physiology or Medicine in 1962. And yes, I remember learning that there was a female X-ray crystallographer who helped them out by taking a photograph of DNA's helical structure. At the time, I never really thought about Rosalind Franklin as anything other than the DNA ”photographer”. But what a triumph for man, and I ended up with that coveted A+ too. And if these memories were the end of my preoccupation for that day, it would have been sufficient.

As I moved forward in my career in science through the years, I realized that Rosalind Franklin’s work was the key to DNA’s discovery and that she was not properly credited for it. In fact, her colleagues had let it slip that her data was obtained without her knowledge. Worse yet, she was not even mentioned in Watson and Crick's Nobel Prize acceptance speeches. Because Rosalind died in 1958 at the young age of 37, she was not even considered for the Nobel, which is not awarded posthumously.  Since then, I started looking up to her as the unsung heroine in science, one of the few brilliant women among the sea of male scientists. In his best-selling biography, The Double Helix, James Watson painted Rosalind Franklin as an unattractive woman from a blue-collar upbringing, and a frustrating scientist who “had to go or be put in her place.” In spite of this unflattering image, her DNA photographs were described as being “among the most beautiful X-ray photographs of any substance ever taken.” But then again, history is written by the victors. Was it sexism in that era that made her colleagues dismiss her so easily? Some claims that her omission was also a result of anti-Semitism.  She was Jewish, born to upper-middle class British parents, and went to a university where largest department was theology. Her uncle, Herbert Samuel, was the first high commissioner of Palestine.  In the epilogue to Watson’s biography, written after Rosalind's death, he acknowledged that he was wrong in his impression of Rosalind, and how she faced great struggles as a woman in science in spite of her brilliance. We will never know Rosalind’s true story, I suppose. And if this story ended here, it would have been sufficient.

The day’s preoccupation reminded me this:  Science has flaws. We look to science to be rational, when too often it is not. Drama, anarchy, lies, fear, and sheer luck all rear their heads in science, just as in any other field of endeavor. Still, I do believe that Watson and Crick deserved the Nobel Prize. Their amazing discovery of how the DNA base pairs interact paved the way for our understanding that a single misspelling or a few letters’ deletion in our 3 billion letters of DNA code can account for rare diseases such as cystic fibrosis. But in many ways, Rosalind’s story is a tragedy. Scientists work for the betterment of the world, typically with minimal reward - prestige and legacy. That’s why successful businessmen have yachts, whereas even the best scientists that I know can boast only of paper boats in their tubs. Truly, Franklin’s DNA story is one for the books - literally. As we celebrate the 50^th anniversary Watson and Crick's Nobel Prize this year, I hope that the newest editions of biochemistry text books include Rosalind Franklin’s role in DNA’s history, and give her the credit that she’s due.  The recognition would come far too late. But, since we cannot change the past, it would be sufficient.

Note: This is an article I wrote for the May issue of The Chronicles, Etz Hayim's monthly newsletter.