The Scientist Who Scrambled Darwin’s Tree of Life

The Scientist Who Scrambled Darwin’s Tree of Life

Woese himself was not an experimentalist. He was a theorist, a thinker, like Francis Crick. “He never used any of the equipment in his own lab,” Sogin said. None of it — unless you count the light boxes for reading film images of RNA fragments, the shorter pieces of the molecule once Sogin had used enzymes to cut them into workable bits. Sogin himself built these fluorescent light boxes, on which the images of the fragments, cast by radioactive phosphorus onto large X-ray films, could be examined. He converted an entire wall of bookshelves, using translucent plastic sheeting and fluorescent tubes, into a single big vertical light box, like a bulletin board. They called that one the light board. Viewed over a box or taped up on the light board, every new film would show a pattern of dark ovals, like a herd of giant amoebas racing across a bright plain. This was the fingerprint of an RNA molecule. Recollections from his lab members at the time, as well as a few old photographs, portray Woese gazing intently at those fingerprints, hour upon hour.

“It was routine work, boring, but demanding full concentration,” Woese himself later recalled. Each spot represented a small string of RNA letters — like the letters of the DNA code, A, C, G, T, but with U replacing the T. The shortest useful fragments were at least four letters long, and no more than about 20. Each film, each fingerprint, represented ribosomal RNA from a different creature. The sum of the patterns, taking form in Woese’s brain, represented a new draft of the tree of life.

The work was deceptively perilous. Sogin described to me the deliveries of radioactive phosphorus (an isotope designated as P32, with a half-life of 14 days), which amounted to a sizable quantity arriving every other Monday. The P32 came as liquid within a lead “pig,” a shipping container designed to protect the shipper, though not whoever opened it. Sogin would draw out a measured amount of the liquid and add it to whatever bacterial culture he intended to process next. “I was growing stuff with P32,” he said, tossing that off as a casual memory. “It was crazy. I don’t know why I’m alive today.”

By 1973, the Woese lab had become one of the foremost users of such RNA-sequencing technology in the world. While the grad students and technicians produced fingerprints, Woese spent his time staring at the spots. Was this effort tedious in practice as well as profound in its potential results? Yes. “There were days,” he wrote later, “when I’d walk home from work saying to myself, ‘Woese, you have destroyed your mind again today.’ ”

George Fox, a rangy young man from Syracuse, came to Urbana in 1973 for a postdoctoral position in Woese’s lab. Fox was not a natural experimentalist and had aspirations to work on the “theoretical stuff,” the deep evolutionary analysis of molecular data, alongside Woese himself. Failing initially to persuade Woese of his aptitude for that, Fox was banished back to the lab, set to the tasks of growing radioactive cells and extracting their ribosomal RNA. But he continued, in flashes, to show his value to Woese as a thinker. Gradually he proved himself, not just sufficiently to work on sequence comparisons but well enough to become Woese’s trusted partner, and sole co-author, on the culminating paper in 1977, with its announcement of a “third kingdom” of life.

The paper announcing that revelation, now considered to be among the most important works ever published in microbiology, is known in the professional shorthand as “Woese and Fox (1977).” But the paper’s immediate reception, by the community of biologists who worked on such subjects, was far from universally admiring. Part of the problem was a matter of scientific protocol: Woese’s discovery had been announced in a news release — issued from NASA, one of his grant sources — just as the paper itself appeared. That offended some scientists. Another factor was that Woese lacked facility as an explainer. He had never developed the skills to give a good lecture. He stood before audiences — when he did so at all, which wasn’t often — and thought deeply, groped for words, started and stopped, generally failing to inspire or persuade. Then suddenly that November, for a very few days, he had the world’s attention.

“When reporters called him up and tried to find out what this was all about,” according to Ralph Wolfe, a microbiologist and colleague, “he couldn’t communicate with them. Because they didn’t understand his vocabulary.” Wolfe helped with growing these organisms in the lab, though he wasn’t credited (or implicated, depending on your view of it) as a co-author on the controversial paper. “Finally he said, ‘This is a third form of life.’ Well, wow! Rockets took off, and they wrote the most unscientific nonsense you can imagine.” The Chicago Tribune, for instance, carried a dizzy headline asserting that “Martianlike Bugs May Be Oldest Life.” The news-release approach backfired, the popular news accounts overshadowed the careful scientific paper and many scientists who didn’t know Woese concluded, according to Wolfe, that “he was a nut.”

(Original source)