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Winner of ‘Genius Award,’ vanguard of extremophile research, pioneer in RNA study, bicycle-loving prof eyes life at a slower pace

Norman Pace, a University of Colorado Boulder distinguished professor in molecular, cellular, and developmental biology (MCDB), is retiring after this semester.

His research and teaching career has been punctuated with prestigious awards, including election to the National Academy of Sciences in 1991 and the MacArthur Fellowship “Genius Award” in 2001. Pace first came to CU-Boulder in 1999 and was named distinguished professor in 2008. Pace has authored or contributed to more than 267 published works.

Over the years, Pace has done groundbreaking work in RNA processing. He discovered new microbes by extracting genetic information from samples unable to be cultured in labs, tracing their genetic relatives.

He was among the vanguard of scientists who discovered the existence of extremophiles, which live in areas long thought to be inhospitable to life—in extremely hot, cold or acidic environments, for instance. Most recently, he studied the prevalence of microbes within the human environment—showers, swimming pools and municipal water.

Pace became interested in microbiology while in high school in the small, farming town in southern Indiana where he grew up. Science education had received a big boost in funding due to the success of 91��Ƭ��’s Sputnik satellite in 1957, and Pace benefited from the proliferation of programs.

He attended a summer institute between his junior and senior year of high school hosted by Indiana University. Along with 60 other students, Pace attended lectures and labs on the campus for two weeks. At the end of the two weeks, 18 students were chosen to work over the next eight weeks in a university lab.

“At that stage of the game, I was planning on attending Purdue and becoming a chemical engineer,” says Pace.

But something changed during Pace’s eight-week lab experience.

“I was meted out to the laboratory of a scientist by the name of Dean Fraser, who at that time was in the Department of Bacteriology,” explains Pace.

The lure of molecular biology

Pace worked with a graduate and post-doctoral fellow on a project that resulted in a published paper—the very first of his long list of publications. More importantly to Pace, he learned about laboratory work and molecular biology. “I was enthralled.”

Pace attended Indiana University for his bachelor’s degree and worked at labs throughout his undergraduate career. He attended the University of Illinois for his Ph.D., and says that’s where he became really interested in RNA, a nucleic acid most widely known for its ability to act as a messenger, carrying instructions from DNA to control the synthesis of proteins in cells.

After his post-doctoral fellowship (also at the University of Illinois), Pace accepted a job in Denver at the University of Colorado Medical Center. With his move to Denver came the inception of his lab—the Pace Lab, which he later brought to CU-Boulder. His lab focuses on RNA processing.

His lab has spent considerable time studying the process of using the structure of ribosomal RNA to infer evolutionary patterns. Pace explains this molecule is particularly suited for conservation, making it great for mapping species and traits.

Pace and the others working in his lab realized that most bacterial life is not able to be cultured and studied within a lab setting, but that by tracing RNA sequencing, microbes would be identifiable. This would also enable them to make correlations between organisms and environments.

Pace says that his lab was doing quite well studying RNA processing, but many other scientists were interested in the same topic. They became attracted to work begun by a scientist named Carl Woese, who was responsible for the three-kingdom model of biological life. This model discards the popular term “prokaryotes,” and its phylogenetic tree consists of Bacteria, Archaea, and Eucarya.

Pace and the others working in his lab realized that most bacterial life is not able to be cultured and studied within a lab setting, but that by tracing RNA sequencing, microbes would be identifiable. This would also enable them to make correlations between organisms and environments.

This discovery led to Pace’s MacArthur Fellowship in 2001. He was able to identify microbial species in areas like underwater hydro-thermal vents (which were thought to be uninhabitable by microbes until then) and hot springs at Yellowstone National Park.

Because the microbes could not be cultured in the labs, Pace and his assistants extracted nucleic acids from large amounts of water and used RNA sequencing to trace relations to the microbes they discovered.

“I knew the next bunch of years was going to be committed to this,” says Pace. “We had found a way to figure out what all this stuff was.”

Pace’s lab published the first metagenomic library. Metagenomics is the study of genetic material taken directly from environmental samples. Over the next decade, the field of metagenomics took off among other scientists, but Pace is proud he was key in its inception.

The bugs in your shower

In recent years, the Pace Lab moved on to another interest: the biology of the human environment. Under funding from the Alferd P. Sloan Foundation, Pace studied human microbiology like non-tuberculosis microbacteria present in moist environments such as saunas and swimming pools—even home showers.

These opportunistic bacteria are non-communicable but abundantly present in indoor, human environments.

Pace studied microbacteria in subway stations in New York City and determined that the microbiology there is essentially the same as the concentration outside the subway.

Pace acknowledges that the New York City subway generally makes people think the microbacteria found would be extensive and “weird,” but credits the normal microbacteria levels to the excellent ventilation system within the stations, driven only by the forced air of the moving subways.

Pace studied microbacteria in subway stations in New York City and determined that the microbiology there is essentially the same as the concentration outside the subway.

Most recently, Pace and his lab studyied microbacteria within municipal water systems. The most striking thing to Pace was the detail. Members of the lab travelled from Salida, Colo., down the Arkansas River to Mississippi, taking samples of water along the way. Some places had high instances of microbacteria, but others were relatively low, sometimes for unclear reasons.

Pace has been pleased to watch members of his lab develop through their innovative research experiences alongside him. The Pace Lab, which hosted 18 members at its prime, has slowed down over the past few years and decreased its members to just a few individuals. The lab will close officially after Pace’s retirement.

Mark Winey, professor and chair of the MCDB department, says it’s been an honor to have Pace on the faculty. “He’s been a leader in the community of microbiologists. He’s served the college by delving into our core curriculum, and he has been an advisor, mentor and fine colleague to so many members of university community, faculty and students alike.”

Pace says that he plans to stay involved with science after his retirement, but that he’ll be slowing down his work substantially.

“It’s going to be very low key,” says Pace. “I have lots of writing yet to do, but I have no specific plans. I don’t play golf.”

Pace is on the board of directors for the Monterey Bay Aquarium Research Institute and sits on the Space Studies Board Committee on Origin and Evolution of Life. He also continues to be involved with his colleagues’ work, some of which involves projects delegated from his closing lab.

Pace also hopes to pursue one of his great—and less well-known—passions after his retirement. Another interest from a young age, Pace is interested in mapping and exploring caves.

A member of the National Speleological Society, Pace was awarded the Bicking Award—widely considered to be the most prestigious award for a “caver” to receive—in 1987 for his work coordinating mapping of cave systems.

The mapping of caves and mapping of biological evolution are both what Pace calls “aesthetically pleasing to do,” and he jokes that “they even pay you money to do the latter!”

He notes that he has stayed with the University of Colorado Boulder longer than he has taught at any other university. An avid bicyclist, Pace attributes making Colorado his home to the beautiful mountains and many biking trails and has no plans to move after his retirement. Pace says he bought a new car three years ago and only recently broke the 7,000-mile-mark.

“I believe in cycling as a way of life,” says Pace. “As I jokingly tell my friends, I will leave Boulder only in an urn!”

Magdalena Rost, a student majoring in classics and English, is an intern for Colorado Arts & Sciences Magazine.