The Johns Hopkins Gazette: June 11, 2001
June 11, 2001
VOL. 30, NO. 37


Saul 'Serendipity' Roseman To Be Feted with Symposia

By Michael Purdy
Johns Hopkins Gazette Online Edition

Saul Roseman, former chairman of the Biology Department in the Krieger School of Arts and Sciences and current Ralph S. O'Connor Professor of Biology, will be honored on June 20 with a symposium featuring presentations by scientists from the United States and abroad, including fellow Hopkins faculty members and current National Science Foundation director Rita Colwell.

The daylong activities of the symposium, which begins at 8:30 a.m., will take place in Mudd Auditorium, Homewood campus.

Symposium organizers made sure to include on the first page of the online program the nickname of the longtime faculty member, who recently turned 80: Saul "Serendipity" Roseman.

Y.C. Lee, professor of biology and a friend of and frequent collaborator with Roseman, said the nickname originated in the 1950s. Roseman, then beginning his career as an assistant professor of biological chemistry at the University of Michigan Medical School, was studying an enzyme that metabolizes sialic acid, a sugar that is an important component of biologically active carbohydrates.

"Two groups, which included two Nobel laureates, had previously announced that they had determined the structure of sialic acid, but during his research Saul found that there was a major error in the proposed structure," Lee says.

While looking for one thing, Roseman had found something else that also was very valuable, the definition of serendipity.

Other assistant professors might have flinched at challenging not one but two Nobel laureates, but Roseman, who had previously had the tenacity as an undergraduate at City College of New York to major in chemistry and at the same time take minors in both biology and physics, stood firm. And he was eventually proven correct.

"Serendipity means when fortune knocks at your door at an unexpected time, you have to be ready to receive her, and Saul was more than ready," Lee says. "That finding catapulted him to international recognition."

Further accomplishments followed in the 1950s. Roseman determined how cells make glucosamine, a key building block in complex carbohydrates. He also identified the most significant sugar transport system in bacteria, a complex of enzymes known as the bacterial phosphotransferase system.

"For a bacterial cell to live, it has to take up nutrients, and the most important nutrient for most common bacteria is glucose," Roseman says. "Glucose has to cross the bacterial membrane, and there's this whole special, complicated apparatus for bringing it across the membrane that we've identified and continue to study today."

Colleagues say Roseman's outstanding record proves that it's possible to make "accidental" discoveries happen through rigorous application of scientific and experimental principles, commitment to being open-minded, and intense, inquisitive attention to results.

For Roseman, who seems more than a little embarrassed at all the fuss of the symposium, serendipity is simply a tool of the trade.

"As far as I'm concerned, serendipity is a major tool of scientific investigation, and many, many major discoveries in biology and medicine have come through it," Roseman says. "Take the human brain for example. We think there's about 100,000 different types of enzymatic reactions that take place in the human brain. When you start from scratch looking for something in that, the chances that you're going to find what you're looking for are pretty low."

The unexpected, Roseman says, is just Nature's way of telling researchers where to look for the really interesting and important stuff.

Roseman came to Hopkins in 1965. He served as chair of the department from 1969 to 1973 and from 1988 to 1990. Lee credits a large portion of the current Biology Department buildings and facilities to fund-raising efforts initiated by Roseman during his first tenure as chairman.

Roseman's current research interests include cell-to-cell recognition and cellular adhesion, two processes essential to embryonic development. Using nascent liver cells from rats and chickens, Roseman's group is working to describe the molecular events that make these processes possible.

Roseman's other major area of research resulted from a request he received from the U.S. Navy.

"About 15 to 20 years ago, the Navy asked Saul to join a research project investigating how they could prevent barnacles from forming on their ships," Lee says. "Barnacles get started when microbes attach to the metal in the hulls of ships. The barnacles come after the microbes to feed on them."

During the course of the research, Roseman identified a microbe with an uncanny capacity for degrading chitin, a substance that gives strength to the shells of boneless animals like crabs, lobsters and insects, and microorganisms like zooplankton.

"Chitin's a highly insoluble compound, and it should be constantly raining to the bottom of the ocean as microorganisms and arthropods die," says Roseman. "But we don't find it in marine sediments, mainly because of bacteria that specialize in feeding on it."

Roseman has been working to describe the highly complex processes used by the bacteria he identified to break down chitin and conserve the nutrient carbon contained within it.

The work has recently turned to Vibrio cholerae, which lives on chitin and is the cause of cholera.

Roseman, who is married to former Hopkins Dean of Academic Advising Martha Roseman, has received many awards and honors, including his 1972 election to the National Academy of Sciences and an honorary M.D. degree from the University of Lund in Sweden.

Asked to describe any other outstanding aspects of his colleague, Lee mentions Roseman's work as a teacher and the eminent positions held by many of his former students.

"And one more thing--he's quite the avid sports fan," Lee says. "The Baltimore Colts were at their prime when he first came here, and it was very tough to get seats. Saul wrote directly to the Colts organization requesting that he be allowed to subscribe, and he got it."