Microcosm: E. coli and the New Science of Life

tags: Microcosm, microbiology, bacteria, E coli, evolution, Carl Zimmer, book review

I lived through Seattle's outbreak of the "killer E. coli strain O157:H7" that charged into the world's consciousness after it mercilessly destroyed the kidneys and other vital organs of hundreds of children and adults who consumed contaminated fast food. During this time, I worked as a lab microbiologist in several human and veterinary hospitals in the Seattle area while I earned my bachelor's degree in microbiology, so I have a strong background in both the practical realities and the scientific lore of bacteria and viruses. Later, as a research scientist, I harnessed the biosynthetic energies of a variety of laboratory strains of E. coli, which frequently function as the workhorses of molecular biologists studying a variety of genes and their products. So of course, with my background, I had to read Carl Zimmer's new book, Microcosm: E. coli and the New Science of Life (NYC: Pantheon Books; 2008), but imagine my surprise when I discovered new information about E. coli in this fascinating and beautifully written story.

Carl Zimmer has done such a remarkable job with this book; transforming an already interesting topic into something that is nearly universal in its relevance. His personable and engaging narrative piques his readers' curiosity as he carefully builds his story from basic scientific findings. As a result, his readers end up learning about complex science in the same way that scientists do: by building upon the discoveries and innovations of the past. Beginning with the isolation and identification in 1885 of Escherichia coli -- E. coli -- as a distinct organism by Theodore Escherich (for whom it was eventually named), Zimmer guides his readers up through present day research where this common gut bacterium is teaching scientists about the fine details of the evolutionary process, natural selection and ecology.

As he tells the fascinating story of E. coli, the author skillfully weaves together relevant details from a variety of important scientific themes. For example, he presents the "splitter" versus "lumper" controversy regarding the classification of organisms where it was hotly debated whether new organisms were truly new species or just a variation upon an already known theme. This might sound esoteric or trivial, but it actually has important implications for the treatment and control of disease since for instance, the dangerous gut pathogen formerly classified into the genus, "Shigella," is actually not a separate species at all: it is the "O157:H7" strain of E. coli! Further, this pathogenic strain of E. coli is new on the scene and more astonishingly, it was created by humans. Scientific research indicates that E. coli strain O157:H7 originally arose roughly one thousand years ago due to the common practice of overcrowding domestic livestock, especially cattle.

How did some of our friendly little gut bacteria, E. coli, become such dangerous killers? Æeons before I and other scientists learned how to add new genes or remove old ones from E. coli, the bacteria were proving themselves to be adroit molecular poker players, and the highly pathogenic "shigella" was only one of its many innovations. As if that wasn't enough, E. coli and other bacteria also relied upon bacterial viruses, or bacteriophage, to help them reshuffle their genetic deck of cards by transferring snippets of DNA between vastly different microbes -- which has led more than a few researchers to hypothesize that viruses themselves are actually powerful machines that help to drive evolution through recombining pieces of DNA that might never otherwise be found next to each other. Indeed, even humans possess remnants of quiescent or recently defunct viruses in their genomes as silent but still recognizable genetic fingerprints.

This readable book is 243 pages long with ten of those pages containing notes for each chapter, followed by a 16-page bibliography of original scientific literature and a 15 page index, all of which are designed to help the interested reader learn more. There are nine black-and-white illustrations and diagrams, and at the beginning of each chapter is a small icon of an individual E. coli bacterium that is in the process of changing direction by 180 degrees -- a visual testimony to the author's desire to understand the mechanism and evolution of the mysterious flagellum that gave birth to this story. This fascinating book is not to be missed. It has something for everyone, from high school and college students to people who are interested in science, from science historians to medical personnel and even scientists -- yes, even professional microbiologists and molecular biologists will enjoy and learn from reading this book.

Carl Zimmer has written numerous articles about science for The New York Times, National Geographic, Scientific American and Discover magazine, where he also is a contributing editor and author of his Discover-hosted blog, The Loom. In 2007, he won the National Academies Communication Award, the highest honor for science writing, and previously earned fellowships from the John Simon Guggenheim Memorial Foundation and the Alfred P. Sloan Foundation. Zimmer is the author of six other books about science: Cerebrum 2008: Emerging Ideas in Brain Science (Dana Press; 2008); Evolution: The Triumph of an Idea (Harper Perennial; 2006); Smithsonian Intimate Guide to Human Origins (HarperCollins Publishers; 2005); Soul Made Flesh: The Discovery of the Brain--and How it Changed the World (Free Press; 2005); Parasite Rex: Inside the Bizarre World of Nature's Most Dangerous Creatures (Free Press; 2001); and At the Water's Edge: Fish with Fingers, Whales with Legs, and How Life Came Ashore but Then Went Back to Sea (Free Press; 1999). He lives in Connecticut with his wife and children.