Biology 103
2000 Second Web Report
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Nanomachines and biological systems: Utopia or Dystopia

Debbie Plotnick

"History will read, Newton, Einstein, Drexler," so contends Bill Spense, the publisher of Nanotechnology Times (1). Technologist Bill Joy, co-founder and chief scientist of Sun Micro-Systems, might agree that Drexler will have an important place in history, but he is not lauding Drexler. It is Joy's assertion that Drexler (considered to be the father of nano-technology) is leading humanity towards the development of what will be ultimately become "the engines of destruction" for life as we know it (2). What is the relevance of the dueling hyperbole of a computer technologist and a self-appointed technology guru?

According to Spense and Joy we sit at the cusp of a revolution, spurred on by Drexler, which will create either a utopia or a dystopia on the earth. Spense and Joy, the yin and yan of perspective with regard to whether biologically modeled, self-replicating, nano-machines will cure all of man's ills and those created by humans or be the greatest destructive force that this planet has ever seen. However, what both men do agree upon is that regardless of the outcome this revolution will bear upon biological systems, presently alive and those yet to come.

Spense often makes references to "Drexlerian nanotechnology," which when first popularly described almost twenty years ago in Drexler's landmark 1986 book The Engines of Creation: The Coming Era of Nanotechnology (3) seemed like a science fiction inspired pipe dream. First, Drexlerian nanotechnology references things built on the scale of a nanometer, approximately the size of a biological molecule. And secondly it invokes the objectives of K. Eric Drexler, who currently chairs the Foresight Institute, whose stated goal is "is to guide emerging technologies to improve the human condition" (4). Since his undergraduate days in the mid-1970's (he holds undergraduate degrees in multidisciplinary sciences, engineering and a Ph.D. in Molecular Nanotechnology from M.I.T (5)) Drexler has championed the promise of nanotechnology. Drexler maintains that humans should, can and must design, create and build molecular sized machines, that will not only act as do the living models upon which they are based, but will also become components of living systems.

Drexler, explains that these machines, which he calls assemblers, will be built one atom at a time (with several hundred able to fit within a single cell) and consist mainly of proteins, synthesized out of carbon, the major constituent of all living things. There is agreement from both sides of the debate that these man-made, nano-assemblers will add untold diversity to the myriad life forms that are presently known. This is because of several interesting differences between assemblers and the biological cells on which they are modeled. One noteworthy difference is that engineers will design the duplication instructions within these hybrid biological/mechanical machines and it will consist of computer code, not DNA.

Drexler and other engineers and nanobiologists envision that these assemblers will, however, still resemble and behave as do existing cell types. Some assemblers would look and act, as do viruses, composed of only proteins and coding material, with reproduction possible only within a host organism. A virus-like assembler would enter a cell and instruct the cell's own internal machinery to replicate, employing the newly imported coding information. Other assemblers would be autonomous and more closely resemble bacteria, carrying within their own rigid boundaries all of the materials necessary for biosynthesis. They might also, as can bacteria, become organelles within eukaryotic cells, thereby making corrections, enhancing or redesigning the original cells.

The motility mechanisms of bacteria, such as flagella, are also envisioned as potential prototypes for nanomachines ambulation within cells or within multi-cellular organisms. A proposal out of the Deptartment of Chemistry and BioChemistry at Utah State University offers that bacteria, such as E.coli and S. typhimurium, might propel nanomachines powered by the chemotactic activity of the bacteria (6). The attached nanomachines would be coded to use the molecular material of its host to produce enzymes of its own design and thereby catalyze reactions that would vary concentration gradients, and thus direct the bacteria to act as a conveyance along a pre-programmed path within a larger organism.

Cornell University researchers also imagine harnessing the chemical reactions that naturally occur within cells to power nanomachines. They propose that nanomachines could be powered by converting the chemical energy of adenosine triphosphate (ATP) into mechanical energy that would supply power to molecular sized motors and integrated circuits, which would operate devices within biological systems, such as the bodies of human beings (7).

Dr. Gregory Fahey, director of research at the Institute for Neural Cryobiology and visiting scholar at Dept. of Biochemistry, University of California at Riverside (8) offers an additional argument as to why seemingly unlimited biological diversity will be brought about by this new technology. Fahey contends "the difference between nanotechnologists and biotechnologists is that the former do not restrict themselves to the biological limitations of the latter..." and that "the real promise for the future, however, lies in the development of fully artificial enzymes" (9). He claims that artificial enzymes will not be limited to the twenty amino acids that nature employs and that these "...amino acids could contain totally non-biological catalytic groups or even pre-made machine parts, such as structural support struts, molecular bearings, or the like..."(9). These new amino acids would also allow for artificial transfer RNA, which could integrate newly imagined parts, with newly imagined functions, into biological entities. These designer molecules will consist of the same basic elements as those of the original biological design. Only those elements could be configured quite differently and thereby greatly enhance existing biological functions as well.

In addition to the possibilities for manipulating biologic functions through new types of enzymes and protein reactions, recent discoveries in physics are expected to bring about super-strong molecular bonds. There is much speculation among nanotechnologists concerning possible uses for the geodesic dome shaped configuration of pure carbon molecules called the buckminsterfullerene, commonly referred to as "fullerenes" or "buckyballs" (10) and related shapes such as "buckytubes." Much of this speculation involves the benefits to humans that would be possible with cells re-enforced or reconfigured out of stronger than diamonds, bucky-shaped nanomachines.

Spense and his optimistic compatriots, such as those at the Foresight Institute, see nanomachines not only as the cure for a number of common causes of death such as cancer, heart disease, diabetes and so forth, but also as the antidote for the cause of death that most people hope for, old age. According to their utopic view, we are within easy reach of designing and implementing nanomachines that are genetically coded to seek out and destroy every scourge man has endured, from bacterial infections; to all viruses including colds and AIDS; to genetic malfunctions, such as cancer. And they declare that the means by which to employ enzymes (of old and new designs) that will turn off or prevent genetic illnesses and malfunctions will soon be realized. And not long after that, they contend, will come the ability to reinforce bones against breaking, cells against tearing, and to rev up nerve cells and neural connections bringing about super-sensing, high speed reactions and hyper-intelligence, when bucky-shaped carbon molecules become standard human equipment (11) (12).

Because nanomachines will be self-replicating and composed of carbon, a most abundant element, the Drexlerians purport that the nano-enhanced, long-lived super human beings will be able to manufacture, atom by atom (thus producing no waste) everything they require and desire (13). Drexler writes in his web-book Unbounding the Future about the myriad of ways in which nanomachines will undo the damage cause by the industrial revolution (14), and thus provide a healthy, clean planet upon which to live long and prosper. Of course the utopians agree that well-fed, long-lived, happy people are also likely to reproduce, but that's no problem, as they allege that these technologies will also enable humans to build (molecule by molecule) out of the most abundant materials in the universe (dirt and air) the means by which to travel and live in space. The energy for such an endeavor will be supplied, they contend, as usual by entopic means. Those thrifty little nanos will be designed to harness the electrical energy that is generated in manufacturing processes, just as they will utilize chemical reactions within cells. Of course, nanomachines could also be programmed to follow the biological example provided by plants, and employ photosynthetic techniques when sunlight or other starlight is abundant.

The misnomered, pessimistic Mr. Joy agrees with the nanoengineers and nanobiologists as to the scientific validity of their arguments. He concurs that soon nanomachines will literally and figuratively be part of our lives. And he concludes, therefore, that the "20th century Weapons of Mass Destruction (WMD), Nuclear, Biological and Chemical (NBC)" will pale next to "the 21st century technologies- Genetics, Nanotechnology and Robots (GNR)" (2). Joy admits, in an article entitled Why the future doesn't need us, that he too was at first seduced by Drexler's vision. However, now that these technologies are no longer just speculative, Joy is convinced that biological-nanomachines are the most dangerous of all because of the very characteristic that makes them remarkable, self-replication.

At every opportunity, on the web, in print, in speeches or in the media, Joy expounds upon Drexler's acknowledgment of a potential danger termed "the gray goo problem" (15). Drexler explains that "gray goo" is neither likely to be gray nor gooey, however, unchecked or uncontrolled, self-replicators do harbor a potential for unpleasant, unintended evolutionary consequences to biological entities, ecosystems or the biosphere. In response to critics, Drexler defensively, accuses them of "biochauvinism," the belief that naturally occurring biological systems possess an intrinsic superiority. But also, quite chauvinistically, Dr. Drexler asserts: "Indeed, if we prevent [grey goo] we will thereby prove our evolutionary superiority" (15).

Clearly, historical precedent is behind Joy's fears. Ecosystems have been devastated, species have become extinct and weapons have wreaked devastation (by governments and terrorists) as a result of technology. But I perceive Joy's alarmism as whinny, not at all like the words of the conscientious scientists who work to guide the world away from nuclear proliferation. Joy stops short of saying something to the effect of "if man were intended to fly, he'd have wings." But he does rather smugly pat himself on the back for being brave enough to shout about the dangers from the GNR technologies, in spite of the fact that "there is no profit in publicizing the dangers" (2). Spence and the utopians claim that nanotechnology will cheaply provide everything humans could need, thereby rendering profit moot. It's true that Drexler and his cheering section could rightly be accused of being overly optimistic and guilty of oversimplification. And it is equally true that these new technologies have the potential for great danger. But neither money, nor power, is the force behind the development of such technologies. Nor is fear likely to stop their development. The motivations behind nanotechnology are the same as for any scientific endeavor - the need to understand how and why things work and the desire to make them work differently. While speculation is interesting, judgments regarding ultimate outcomes are pointless.

WWW Sources

1) NanoTechnology Magazine

2)"Why the future doesn't need us."

3) Web version of Engines of Creation.

4) Home Page Foresight Institute

5)Biographical Information on K. Eric Drexle

6) Design and Development of A Nanoscale Microorganism Based Power Unit

7) National Science Foundation funding launches Nanobiotechnology Center at Cornell

8) The Institute for Neural Cryobiology

1) Nanotechnology in Medicine by Dr. Gregory Fahey

10) Buckyballs - a new sphere of science

11) Re: Drexler on immortality, source of nano books

12) Nanotechnology Health: Life Extension

13) Nanotechnology: The Pursuit of Happiness

14) chapter 9 Unbounding The Future

15) Chapter 11 Unbounding The Future: The Engines of Destruction

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