What Is Life?: Investigating the Nature of Life in the Age of Synthetic Biology

That's a didatic book about the history of the chemical and biological discoveries about life and the meaning of life's concept. Sometimes it's boring, because of the didatism, but, in general, it's a good book, specially to those who like science history and its development.

The recent book by Ed Regis, "What is Life? Investigating the Nature of Life in the Age of Synthetic Biology", may be considered the third of a series. In 1945, Edwin Schrodinger, of the "Schrodinger Equation" that can (with strenuous labor) calculate the properties of any atom's electron cloud, and whose eponymous Cat defines the dilemma of quantum phenomena in a macroscopic world, wrote "What is life? The Physical Aspect of the Living Cell", in which he did not answer the title question, but explored life phenomena from a strictly chemical and physical aspect. He predicted crucial aspects of the genetic code a decade or two in advance of their discovery. Then in 1995 Lynn Margulis brought certain of the same themes more up to date in "What is Life?", shortly thereafter revised and reprinted with her son Dorian Sagan as co-author. As Ed Regis reports, Margulis and Sagan answered the question in so many ways that it is not answered at all. Author Regis begins his book with a look at the formation of a four-way consortium in 2002, with the aim of specifically creating a living cell not based on previously living matter. To date, the effort has not succeeded, but as Edison would have said, they are learning a great number of things that don't work...and a few that offer tantalizing clues to what might work. So much so, that the government is now interested, as evidenced by the Los Alamos Protocells web site (protocells.lanl.gov) and its link to protocell.org, a jumping-off place to a handful of major efforts in the Synthetic Life arena. Regis does home in on an answer, a minimalist definition that life is "embodied metabolism". A few caveats are needed, such as a measure of autonomy and of self-repair, for example: An automobile consumes fuel and moves about, but does not direct its own motions nor maintain itself, while a portion of the metabolism of living cells goes to structural regeneration and growth. And "embodied" is needed to distinguish living matter from open flames. More generally speaking, living things not only metabolize, they also reproduce and evolve. Not every individual will do so, but all can do so. And, specifically for all life that we know, all life processes are directed by coded instructions. DNA carries the instructions, while RNA plus proteins carry them out. Synthetic cells could be based on DNA, RNA and proteins, or it could instead use different chemistry, perhaps not even based on carbon. But whenever a wholly synthetic "embodied metabolism" gets cranked up, performing as cells perform, I suppose we'll have to dub it "living". This is quite a step beyond our fearsome archetype, the Frankenstein monster. That creature was supposedly produced by re-animating a sewn-together collection of bits of corpses. Certain partial successes in the synthetic life area have been analogous to this. But the goal is to create living cells from chemicals, not from various bits taken from other cells. The rub comes if the creators o

"What is the meaning of life?" is a question all must ponder at some point or other. But that's too fancy; try the even more basic, "What is life?" In 1944, Nobel prizewinner and quantum physicist Erwin Schrödinger published a small book with that question as a title, and it has been enormously influential, cited and debated ever since. There have even been other books with the same title since then, trying to definitively corral a huge and amorphous subject. Now science writer Ed Regis has added another, to take in the philosophical and biological efforts of our times: _What Is Life?: Investigating the Nature of Life in the Age of Synthetic Biology_ (Farrar, Straus, and Giroux). My guess is that it is not going to be the last book of the title; the definition game demands that new discoveries and ideas have to play their roles in our understanding of what life is. However, we are on the brink of making cells out of basic molecules, and Regis has a good introduction for those of us who are living through an extraordinary time in experimental molecular biology. Schrödinger's book was a last stand against vitalism, the idea that there was something going on within creatures, organs, and cells that science could not understand. Life chemistry was thoroughly within known laws of thermodynamics. If what goes on in a cell is really only the jostling, linking, and breaking up of atoms and molecules, it makes sense that scientists could just get the right atoms and molecules together and get the whole thing going from scratch. The problem, of course, is that the whole mess is extraordinarily complicated even for the simplest of cells. Regis gives a good short history of how we came to know how complicated it all was. Definitions of life have been said to include necessarily reproduction (but mules are sterile, and are still alive) and also evolution (but evolved or evolving or not, any particular animal is still alive). What really needs to be taken into account in a definition of life is metabolism, the sum total of bodily chemical processes, including molecules into a body and molecules out of it. "Embodied metabolism" is, Regis writes, "at least as adequate as any other definition of life that has been offered to date." Adequate, but like any other definition, it gets iffy at the edges. What about viruses, that do have bodies, if you can call a chemical capsule a body, but are just inert chemically until they find a cell to latch upon and infect? There is something disconcerting about just chemicals connecting and disconnecting being all there is to the living process. By some changes in degree, inert carbon, hydrogen, oxygen, and the rest, eventually become living creatures, and even develop consciousness. And yet, vitalism is dead; "There must be more to life" is true on philosophical levels, but not biological or biochemical ones. That this is more clearly becoming true is shown in Regis's fascinating descriptions of current eff

In 1944, Austrian physicist Erwin Schroedinger published a book with the same name as the current volume: "What Is Life?" Popular science writer Ed Regis points out that Schroedinger "wanted to challenge the notion that at the core of life was some impalpable excrescence that lay beyond the grasp of science." This optimistic view holds that life can be explained in the same terms, and by the same laws of physics and chemistry, as those that pertain to everything else in nature. To be sure, life is exceptional, but it is rule-governed and law-abiding; there is nothing inherently magical or mystical about it. Ultimately, scientists will be able to unravel all of life's mysteries. Present-day scientists are not so sanguine. The question, "What Is life?", Regis suggests, lies more in the realm of religion, philosophy, and metaphysics--and by extension, politics and ethics--than in the realm of science. At first glance, a tangential approach to the question, "What is life?" promises a satisfying solution: "Unquestionably, if there was anything that appeared obvious about what it meant to be alive, it was possessing the ability to die." One's hopeful expectations of an answer, however, are dashed by this consideration: There is no agreement concerning what death is. In between life and death there is often "a state of near-death, or pseudo-life." If one insists on a scientific answer, Regis suggests the following, "Defining life as embodied metabolism . . . seems to be the most defensible theory we have at the present." If you expect a definitive answer to the question "What is life?", this book will disappoint you. Ed Regis holds a Ph.D. In philosophy from New York University and taught for many years at Howard University. He is now a full-time science writer, contributing to Scientific American, Harper's Magazine, Wired, Discover, and The New York Times, among other periodicals. He is the author of several books, including The Biology of Doom: The History of America's Secret Germ Warfare Project.