Carl Richard Woese

Carl Richard Woese, born in 1928, American microbiologist who discovered the archaea, a group of microorganisms with a genetic makeup so different from all other living things that they constitute a separate category of life. This discovery overturned long-held ideas about the scientific classification of life on earth.

Born in Syracuse, New York, Woese received a bachelor’s degree in mathematics and physics from Amherst College in 1950. He continued his studies at Yale University, where he earned a doctoral degree in biophysics in 1953. He performed postdoctoral work at Yale until 1960, when he accepted a position as a biophysicist at the General Electric research laboratory. Woese left this post in 1964 to become a professor of microbiology at the University of Illinois, where in 1996 he became the first recipient of the Stanley O. Ikenberry Endowed Chair.

While at the University of Illinois, Woese turned his attention toward determining the origins of life on earth. He meticulously analyzed ribosomal ribonucleic acid (rRNA), genetic molecules that coordinate part of protein production. Because rRNA shows only slight variation from one generation to the next, it is an excellent tool for revealing the evolutionary, or family, relationships among organisms. Woese spent nearly a decade analyzing the rRNA of various types of bacteria and arranging them into a microbial evolutionary tree.

In 1976 American microbiologist Ralph S. Wolfe suggested that Woese apply his technique to a group of heat-loving microorganisms, then believed to be bacteria, many of which do not require oxygen or sunlight to live. In 1977 the pair found that the rRNA structure of these organisms did not match that of bacteria. Due to their structural differences, these microorganisms could not be accurately placed anywhere in the accepted scientific classification scheme, in which all organisms are divided into prokaryotes (the bacteria and blue-green algae) and eukaryotes (all other organisms, including fungi, plants, and animals). In light of this discovery, Woese proposed that life on earth be categorized into three domains: archaea, bacteria, and eukarya.

Woese’s proposal, initially disregarded by most prominent scientists who questioned his technique, gradually gained widespread support in the scientific community. In 1996 a group of scientists deciphered the entire genetic code of a type of archaea that lives at the edge of undersea volcanoes. The scientists found that the genetic material of the organism was unlike any previously seen in the biological world, finally confirming the assertion Woese had made 19 years before.

In 1984 Woese received a prestigious research grant from the John D. and Catherine T. MacArthur Foundation. He was elected to the National Academy of Sciences in 1988, and in 1992 he became the 12th recipient of microbiology’s highest honor, the Leeuwenhoek Medal.