Friday, July 16, 2010

The Eighth Day of Creation

I recently finished reading The Eighth Day of Creation, a wonderful history of molecular biology by Horace Freeland Judson. The book is divided into three parts: 1) DNA—Function and Structure: the elucidation of the structure of deoxyribonucleic acid, the genetic material, 2) RNA—The Functions of the Structure: the breaking of the genetic code, the discovery of the messenger, and 3) Protein—Structure and Function: the solution of how protein molecules work. The first part centers on the story of how Watson and Crick discovered the double-helix structure of DNA, a story also told in Watson’s book The Double Helix (required reading for any would-be scientist). I was less familiar with the RNA tale in the second part, but was fascinated by the ‘Good Friday” meeting in which the various roles of RNA (as both a messenger taking the genetic information from DNA to the protein, and as part of ribosomes where protein synthesis takes place) was first understood by Sydney Brenner and Francois Jacob, among others. I was somewhat familiar with Kornberg’s deciphering of the genetic code from my days at the National Institutes of Health, where Kornberg worked. The last section tells how Max Perutz used X-ray crystallography to determine the structure of hemoglobin, the first protein structure known.

New to me was the story of Jacques Monod and his study of bacteria, which led to our understanding of how protein synthesis is controlled. Last week in this blog I mentioned seeing a display about Monod at the Pasteur museum in Paris. Particularly fascinating was the story of Monod’s role as a leader of the French resistance against the Nazis during World War II, and how he continued his scientific research while participating in the resistance. Judson writes
“In the autumn of 1943, a meeting was called in Geneva of representatives of all the armed groups of the French resistance, to coordinate their military actions. Just before the meeting, Philippe Monod heard from his brother that he was the delegate of the Francs-Tireurs from Paris. In November, the Gestapo arrested a minor agent of one of the main resistance networks in France, Reseau Velites, centered on the Ecole Normale Superieur. Marchal’s identity [Marchal was an alias used by Monod] and activities were known to the agent. Monod had to go underground completely, leaving his apartment, never sleeping more than a night or two at one address, staying away from the Sorbonne. On 14 February 1944, the Gestapo caught Raymond Croland, chief of the Reseau Velites, who knew Monod.

On the run from his own laboratory, Monod was given bench space by [Andre] Lwoff. ‘I don’t think I was ever searched for, actually,’ he said. ‘But the possibility existed because at least one—in fact, several men had been picked up who knew what I was doing and who knew my name and where I worked. But it was known that I lived near the Sorbonne and worked at the Sorbonne, so the Gestapo would have had no reason to hunt for me at the Pasteur Institute.’ In Lwoff’s laboratory, in collaboration with Alice Audureau, a graduate student, Monod that winter began a new set of experiments….”
I would rank The Eighth Day of Creation second in my list of the best scientific histories I have read, just behind Richard RhodesThe Making of the Atomic Bomb, and just ahead of Bruce Hunt’s The Maxwellians. Interestingly, some of the characters who appeared in The Eighth Day of Creation also played a role in The Making of the Atomic Bomb: in particular, George Gamow and Leo Szilard (Szilard was mentioned in the very first sentence of Rhodes’ book). Readers of the 4th edition of Intermediate Physics for Medicine and Biology will be interested in learning that many of the pioneers in molecular biology were trained as physicists. Judson writes “new people came into biology, and most famously the physicists: Max Delbruck, Leo Szilard, Francis Crick, Maurice Wilkins, [and] on an eccentric orbit George Gamow.” I couldn’t help but be struck by the central role of X-ray crystallography in the history of molecular biology. Under physicist William Bragg’s leadership at the Cavendish, four Nobel prizes were awarded (in the same year, 1962) for molecular structure determination: Watson and Crick for DNA, and Perutz and Kendrew for the structure of hemoglobin and myoglobin. I highly recommend the book, especially for young biology students interested in the history of their subject.

I will end with the opening paragraphs of the Eighth Day of Creation, where Judson draws parallels between the revolutions in physics in the first decades of the 20th century and the revolution in biology in the middle of the century.
“The sciences in our century, to be sure, have been marked almost wherever one looks by momentous discoveries, by extraordinary people, by upheavals of understanding—by a dynamism that deserves to be called permanent revolution. Twice, especially, since 1900, scientists and their ideas have generated a transformation so broad and so deep that it touches everyone’s most intimate sense of the nature of things. The first of these transformations was in physics, the second in biology. Between the two, we are most of us spontaneously more interested in the science of life; yet until now it is the history of the transformation of physics that has been told.

The revolution in physics came earlier. It began with quantum theory and the theory of relativity, with Max Planck and Albert Einstein, at the very opening of the century; it encompassed the interior of the atom and the structure of space and time; it ran through the settling of the modern form of quantum mechanics by about 1930. Most of what has happened in physics since then, at least until recently, has been the playing out of the great discoveries—and of the great underlying shift of view—of those three decades. The decades, that shift of view, the discoveries, and the men who made them are familiar presences, at least in the background, to most of us; after all, they built the form of the world as we now take it to be. The autobiographies of the major participants, their memoirs and philosophical reflections, have been composed, their biographies written in multiple—and they remain long in print, for these were men of intelligence, originality, and, often, eccentricity. The scientific papers have been scrutinized as historical and literary objects. The letters have been catalogued and published. The collaborations have been disentangled, the conferences reconvened on paper with vivid imaginative sympathy, the encounters, the conversations, even the accidents reconstructed.

The revolution in biology stands in contrast. Beginning in the mid thirties, its first phase, called molecular biology, came to a kind of conclusion—not an end, but a pause to regroup—by about 1970. A coherent if preliminary outline of the nature of life was put together in those decades. This science appeals to us very differently from physics. It directly informs our understanding of ourselves. Its mysteries once seemed dangerous and forbidden; its consequences promise to be practical, personal, urgent. At the same time, biology has been growing accessible to the general reader as it never was before and as the modern physics never can be. Indeed, part of the plausibility of molecular biology to the scientists themselves is that it is superbly easy to visualize. The nonspecialist can understand this science, at least in outline, as it really is—as the scientist imagines it. Yet the decades of these discoveries have hardly been touched by historians before now. The Eighth Day of Creation is a historical account of the chief discoveries of molecular biology, of how they came to be made, and of their makers—for these, also, though only two or three are yet widely known, were scientists, often of intelligence, originality, even eccentricity.”

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