Starting an independent career
My first experiment [at Brookhaven National Laboratory] was on ribosomes, in which I tried to settle an emerging controversy about whether the proteins and RNA in the 30S subunit were asymmetrically distributed. This resulted in my first independent paper being a single author paper in Science . Since this was a decade before the internet, I wrote a letter to my father in India when it was accepted, and about a month later received his reply saying that he was glad I had made a good start, and that if I continued to work hard, I might some day even have a paper in Nature .
[Dr. Ramakrishnan went on to do a sabbatical at the MRC Laboratory in Molecular Biology at Cambridge, England in late August 1991 to learn crystallography, as he felt that was how he could answer the really important questions in his field. Having learnt the nuts and bolts of how to solve a structure, he returned to the U.S. and moved to the Biochemistry department of the University of Utah.]
Starting work on the 30S subunit at Utah
Even before coming to Utah, I had ideas of solving the structure of the ribosome, beginning with its small or 30S subunit. My first task was to convince someone in the lab that this was a worthwhile project.
The project really took off when the graduate students came on board. [Bil Clemons, John McCutcheon, Brian Wimberly and Joanna May joined the team.]
As soon as we started, my insecurities about funding again set in. I could just imagine writing a grant application to NIH saying that we had no good crystals of the 30S subunit but had some ideas about how to get them, and that although a group had been working on good crystals of the 50S subunit for almost a decade, we had some ideas for how to solve our structure if we got good crystals. Having served on study sections myself, I could just imagine the peals of laughter that would go around the table as my application was considered.
On the other hand, I knew that the LMB, where I had done my sabbatical, had a longstanding tradition of supporting exactly this kind of difficult but fundamentally important project. Apart from funding issues, I felt I would have access to world leaders in crystallographic methodology who could help me if I ran into technical problems.
So I wrote again to Richard Henderson, who by that time had also become the director of the LMB, and we agreed that I would visit on my way to a ribosome meeting in Sweden. After my talk on ribosomal proteins, Richard and Tony Crowther (who was joint head of the division with Richard) chatted with me for a couple of hours on the “ribosome problem.” They were interested in my ideas, what the competition was likely to be, what approaches had failed, what resolution one would have to reach to achieve a significant breakthrough in understanding and how long that was likely to take. The conversation was unlike any other job interview. There was no discussion of space, salary or equipment, just about science and ideas.
At the time, I had no crystals; nevertheless Richard wrote shortly after my visit saying they were interested in supporting me, and would let me know when they would have the additional space to accommodate me. A few months later, Richard wrote again to say that indeed the space had materialised.
I suddenly had to make what was one of the hardest decisions of my life: whether to gamble everything on going to the LMB and work exclusively on this project, which would involve taking a large salary cut and leaving our families (including our grown children) in the USA, or to continue working in Utah, where I would probably have to hedge my bets by working on safer projects simultaneously. In the end, I decided that the structure of the ribosome was the most important goal in my field, the time was ripe for an attack on it, and it would be a mistake to be distracted from it by other projects because there was only a narrow window of opportunity before other groups entered the field that had so long been dominated by just one person, Ada Yonath.
Most people thought that it would be insane to move to England staking all on this one risky project. Vera and I finally decided to leave Utah where we were very happy, take a 40 per cent salary cut and move to the LMB.
With the decision to move to the LMB made, I decided to focus entirely on the 30S subunit. Within a few months we had crystals, and a few months later, we had cracked the problem of getting them to diffract well. This was largely due to John and Bil's willingness to try completely new approaches to purifying the 30S subunit and to their sheer dedication and hard work.
Work at the MRC Laboratory of Molecular Biology
I moved to Cambridge in April of 1999, while Brian, Bil and Joanna stayed behind. The result was that I was able to make use of the LMB's computing resources to try several phasing runs in parallel, and send the maps to Utah. Because of the seven-hour time difference, we may have been the only group that actually speeded up to some extent as a result of a move.
So only a few months after my move to Cambridge, we had made a major breakthrough in tracing [the entire central domain of the 30S subunit.] When I revealed our findings at the triennial ribosome meeting in Denmark in June, I could sense the shock in the audience, especially since virtually none of them knew we were working on the problem. Soon afterwards, our work was published in Nature in August 1999 with much fanfare.
By this time, Brian and Bil had moved from Utah, and we needed to focus on getting to high resolution.
Solving the 300S subunit structure
Getting to the high-resolution structure of the 30S subunit was beset with problems, which are described in the Nobel lecture. This was a particularly stressful time for me and my lab members. The Yale group of Tom Steitz, Peter Moore and their colleagues was making steady progress with their structure of the 50S subunit. More significantly for us, soon after we had decided to focus on the 30S subunit in Utah, I had found out that Ada Yonath, who had first crystallised the 50S subunit and had been working on determining its structure for over a decade, had now essentially switched to determining the 30S subunit structure using crystals obtained by a slightly different route. So instead of having a quiet niche to myself, we were in a flat-out race.
Given the competition, we wanted to ensure that our data collection at the [Advanced Photon Source (APS) in Argonne in February 2000] was a success, since it was not clear that we could avoid being scooped if that trip failed. [Team members] froze over a 1000 crystals in the cold room while listening to Johnny Cash on a mini stereo system. Four of us worked in 12 hour shifts using a large spreadsheet that told us which crystals we had to look at next. Ditlev used his computing skills to streamline our data collection and analysis procedures. We calculated an anomalous difference Fourier map while still at the beam line, and when I saw the large number of strong peaks for our best derivative, much to Rob's amusement, I started dancing around the office saying, “We're going to be famous!”
The maps from the improved data were stunning, and we were on our way to building the structure. With five of us working long hours, were able to build a complete atomic model for the subunit within weeks. Even before we had finished, Andrew Carter had crystallised the subunit with three different antibiotics, and seeing them directly in difference Fourier maps was another great highlight.
The structure of the 30S subunit led to a number of follow-up studies on antibiotics and ligand binding. The most important of these, largely carried out by James Ogle, led to understanding how the ribosome ensures the accuracy of translation during decoding of the genetic message. Our studies on decoding continue to this day in the context of the whole ribosome.
The politics of scientific recognition
People go into science out of curiosity, not to win an award. But scientists are human, and have ambitions. Even the best scientists are often insecure and feel the need for recognition. Our ribosome work led to lots of invitations to give seminars and speak at conferences. It resulted in my election to the Royal Society and the U.S. National Academy of Sciences and also led me to receive a prestigious European prize, the 2007 Louis-Jeantet prize for medicine. Thus in both my scientific efforts and the recognition for it, I had succeeded beyond my wildest dreams.
Although few scientists are foolish enough to enter a field to win a Nobel Prize, ever since the 30S subunit had been solved, people would regularly bring up “the Prize” in conversations whenever I went to conferences or give seminars. It was clear to me that the ribosome was at least as important as other structures that had been awarded the Nobel Prize. But there were many more than three people who had contributed to the ribosome, even if one only counted principal investigators, which itself is a fictional view of the way modern science is done.
While we were solving the structure of the 30S subunit, I had mostly refused to be distracted by going to meetings to speak about our work. So it was something of a shock when only a couple of months after the atomic structures of the subunits came out, a prize in the USA was awarded to just one aspect of the ribosome, peptidyl transferase. It seemed to me that instead of waiting for the impact of the ribosome work to become clear and then thinking hard about what had really made a difference to the field, the committee had hurriedly decided on which three people they wanted to honour and then written a citation around them that would exclude the others. Richard Henderson, my director, suggested that I should accept more invitations to meetings and talks to get our story known if only to get proper recognition for our work, regardless of prizes.
Deep down, I felt that the scientific event that transformed the field more than anything else was the determination of the atomic structures of the ribosomal subunits and the functional studies that followed as a result, to which we had made a major contribution. However, international prizes for work on ribosomes always seemed to go to other people. So over the years, I had gradually come to accept that I would probably not get a major international prize for the ribosome, least of all the Nobel Prize. Once I had accepted that, I felt liberated and happier, but I have to confess that I felt some trepidation each October. Every time I learned the Nobel Prize was for something other than the ribosome, I would be relieved because it was a postponement of what I felt would be the inevitable disappointment. As the years went by, it seemed to me and many other scientists that there would never be a Nobel Prize for the ribosome because the problem of choosing three people out of all the contributors appeared insurmountable.
The Nobel Prize and its immediate aftermath
On October 5, 2009, the Nobel Prize for Physiology and Medicine went for work on telomerase. Since the Chemistry prize had been awarded for biological work the previous year, I was confident that it would not be awarded for the ribosome that year.
On the morning of October 7, I was halfway to work when my bicycle developed a flat tire. As a result, I came in quite late and somewhat irritated, and had completely forgotten that it was the day the Chemistry Prize was going to be announced. So when the phone rang soon afterwards and a voice said it was an important call from the Royal Swedish Academy of Sciences, I immediately suspected it was a prank orchestrated by one of my friends like Rick Wobbe or Chris Hill, who like practical jokes. When Gunnar Öquist came on the line and started talking to me, at first I simply refused to believe him and even complimented him on his Swedish accent. Finally, after he was done, I asked if I could speak to one of the committee members, Måns Ehrenberg, whom I knew personally. When I heard his voice, it was with a shock that I realised it was true, a feeling that was reinforced when Anders Liljas and Gunnar von Heijne also came on the line to congratulate me.
Two members of my lab, Martin Schmeing and Rebecca Voorhees, had desks just outside the open door to my office and had overheard my end of the entire conversation. They did not share my scepticism and could hardly contain themselves. By the time I got off the phone, they were jumping up and down, and Martin popped open a bottle of champagne he had been saving to celebrate the publication of a paper that had just been accepted in Science . In the intervening minutes between the phone call and the public announcement, I was unable to get hold of Vera, because she was taking a walk with Tanya and does not use a mobile phone. It was 2 a.m. in Seattle and 5 a.m. in New York, so I did not want to wake up my father, sister, or Raman. Unfortunately, the press was not so considerate.
It was not until I saw the public announcement on the Nobel website that it fully sank in. Within a few minutes, the phone rang and did not stop ringing for two days. My colleagues at the LMB, many of whom had supported me when I had nothing but an idea, were delighted. They organised the customary drinks celebration in the canteen, for which Mike Fuller bought and served the champagne as he had for all the previous Nobel Prizes awarded to scientists here. After the celebration, Vera and I walked my bicycle home in the rain.
It was touching to get congratulatory messages from old friends and scientific colleagues around the world. I was especially moved by messages from colleagues in the ribosome community, including my mentor Peter Moore and Joachim Frank, both great scientists who had made major contributions to the field and were justifiably contenders for the prize themselves. Peter was particularly (and typically) gracious, and seemed proud that his protégé had done so well. Much was made of my prize in India, and I found myself the subject of an entire nation's celebration. I was taken aback by the flood of emails from complete strangers in India, and when they continued unabated for several days, I overreacted to what I felt was an intrusion on my ability to carry out my work. This angered many people there and a clarification I made only partly mollified them.
The Nobel week in Stockholm in December was surreal and memorable. After Sweden, I went on my usual annual visit to India, but this time with some trepidation because I did not know what the reaction to me would be given the email controversy. I need not have worried, because I was overwhelmed by the warmth and affection from both members of the public and my scientific colleagues there. I was honoured that the Government of India decided to bestow upon me their second highest civilian award, the Padma Vibhushan. I have come to realise that I have inadvertently become a source of inspiration and hope for people in India simply by the fact that I grew up there and went to my local university, but could nevertheless go on to do well internationally.
On my return to Cambridge in early January, things slowly began returning to normal after the euphoria of the autumn. I began to realise that the Nobel Prize could be seen not just as an affirmation of my past work but also as an encouragement to continue to work on interesting problems. Certainly, it seems to have fired up people in my laboratory, and I look forward to the struggles ahead as we try to answer some of the hard questions in our field and beyond. Looking back on my life so far, I feel a deep sense of gratitude for having been able to lead such a rich life both intellectually and personally. — © Nobel Foundation
( This is the concluding excerpt from an autobiographical essay by 2009 Nobel Prize winner for Chemistry V. Ramakrishnan, made available exclusively to The Hindu . The entire essay is now available at The Hindu website and will be published by the Nobel Foundation in a few months. )
