The Life of a Virus: Tobacco Mosaic Virus as an Experimental Model, 1930-1965 (review)

Tobacco mosaic virus (TMV), the agent that causes mottled lesions on the leaves of tobacco and certain other plants, is one of the earliest recognized examples of what are now called “filterable viruses” or simply “viruses.” Since the late nineteenth century, the nature of this agent has fascinated biologists, chemists, and even physicists. Because, in general, knowledge about a particular organism fuels further interest in that organism, TMV became established as a “model virus.” What was true for TMV became true for all viruses.

The Life of a Virus explores the research in the mid-twentieth century that firmly established TMV as a crucial experimental model for understanding viruses, per se, as well as for the approaches and paradigms of the new field of molecular biology. Centered on the work of Wendell Stanley and his colleagues, this history shows how research on TMV as a representative virus answered questions about the nature of viruses in general, the origins of life, and the genetic code. As biological knowledge grew, TMV kept up with the times. New technology and new biological knowledge were interdependent. Both ultracentrifugation and electron microscopy were crucial methodologies that contributed to TMV research and, at the same time, were validated by it. At every turn, TMV proved its worth: from its purification and crystallization in the 1930s to its dissociation into protein and nucleic acid components, followed by reconstitution of infectious virus in the 1950s, to its use in the 1960s linking changes in its RNA to changes in its protein coat, thus establishing the principle of a genetic code.

Angela N. H. Creager, a biological chemist turned historian of science, lays out this history to emphasize model systems (a system includes a specific organism together with a collection of experimental procedures and fundamental assumptions) as exemplars of scientific activity. Her approach exposes the connections that link biomedical, agricultural and fundamental research communities and the web of interactions that occurred in the day-to-day laboratory work on TMV. This book provides a compelling historical analysis that encompasses the diversity and messiness of actual scientific research, a perspective that I am tempted to attribute to the author’s experience of having “been there and done that.” She avoids the seductive attractions of “high theory” that often seems to force-fit historical evidence into normative, predetermined categories. Instead, Creager provides a balanced and detailed account of the complex network of research on TMV interwoven with the social and administrative contexts of mid-twentieth century biomedical science. Life of a Virus is a valuable addition to the growing scholarship aimed at a critical and nuanced analysis of the origins, growth, and development of molecular biology.