Klaenhammer has seen great changes as new genetic technologies have dramatically redirected the focus of his research.
So when the phone call came on May 1 from Dr. Ron Phillips at the National Academy congratulating Klaenhammer on his election to the prestigious body of scientists, he was sure it was a practical joke. He double-checked the date — not April 1. Then, as researcher after researcher from the National Academy came to the phone with personal congratulations, the reality of the honor began to dawn on him.
Klaenhammer says his election is the greatest recognition of his professional career. His group has received a number of research awards, including the Borden Award, the highest award given by the American Dairy Science Association, and the Research and Development Award of the Institute of Food Technologists.
But it is his commitment to his graduate students that is evident when he speaks with equal pride of the six Kenneth R. Keller Awards that his doctoral students have received between the years of 1983 through 2000. The Keller Award, which carries a $1,000 prize, is given annually to the student in the College with the most outstanding doctoral dissertation.
Klaenhammer was recognized in 1993 for his commitment to teaching when he was named a N.C. State University Alumni Distinguished Graduate Professor.
“I think that working with graduate students is the most gratifying part about my job,” he said. “You are working with very intelligent, creative and motivated young people who are intent on learning the scientific process and finding their own professional paths.
“The graduate experience is a learn-as-you-go process for the students and the adviser,” he said. “Each student is unique, bringing special talents and perspectives to the questions that are posed by the group, the discipline and the moment in time. There is no greater experience than working with dedicated and motivated young people. They remain part of your scientific family throughout your career.”
Klaenhammer came to the College’s Food Science Department in 1978 as an assistant professor and has worked there his entire career. He was drawn to N.C. State from his home state of Minnesota to work in the nationally recognized food and dairy microbiology group led by Dr. Marvin L. Speck, William Neal Reynolds Professor emeritus of food science and microbiology. Speck worked with preservation methods for dairy starter culture bacteria and developed Sweet AcidophilusTM milk, using the probiotic bacteria, Lactobacillus acidophilus NCFM.
Speck recalls that Klaenhammer’s name came up when he started looking for a new faculty member in the late 1970s. When food science faculty interviewed him, Klaenhammer still had a year’s work on his doctoral program. “We were so impressed with the interview and with the lecture he gave, we waited a year to get him,” said Speck, who retired from N.C. State in 1979.
“There’s no question in my mind that Todd is one of the most outstanding people in microbial genetics,” Speck said. “He is very able to see the benefits in the preparation of foods that rely on microorganisms.”
Klaenhammer earned a bachelor’s degree in microbiology at the University of Minnesota and did some undergraduate research in medical microbiology. He went on to earn master’s and doctoral degrees in food science there as well.
His graduate advisior, Dr. Larry McKay, was responsible for the seminal discovery of plasmid DNA elements in dairy starter cultures and then correlating their presence with properties that are essential for the bacteria’s ability to grow and ferment milk. It was his association with McKay that piqued Klaenhammer’s interest in food microbiology, microbial genetics and dairy starter cultures.
Klaenhammer’s work in the College runs the gamut from the most basic science to the most applied. His long-term efforts have focused on understanding how fermentation cultures resist attack by viruses called bacteriophages. The bacteriophages appear constantly in milk fermentations and often slow or stop the fermentation in food processing.
His group was the first to characterize the major defense systems used by starter bacteria that ward off phage infection and then, relying on genetic techniques, they moved these defenses into industrial starter cultures used in cheese plants. Later, his group stacked different defenses together, providing the cultures with more powerful and complementary defenses.
The group also has studied how bacteriophages evade the defenses and evolve new virulent types in dairy plants. With this information, the group found ways to close the genetic routes the viruses used to evolve new virulent types. Today, the strategies developed by Klaenhammer’s group are covered by seven U.S. patents, and the approaches are used worldwide in the fight against the bacteriophages that infect food and dairy fermentations.
“Todd has made quite a name for himself developing strains of lactic acid bacteria that are phage-resistant,” said Dr. Ken Swartzel, head of the Food Science Department. “He has really pioneered an area of research. People all over the world follow his path.”
Currently, his research group has expanded into the arena of functional genomics, mostly on Lactobacillus species that exert benefits to human health, known as probiotic bacteria (meaning “in favor of life”). Work from around the world, including the College’s own Microbiology Department through Dr. Walt Dobrogosz’s group, is showing that probiotic lactobacilli can stimulate the immune system and promote resistance to enteric infections. Klaenhammer’s group is busy searching for the genetic basis by which some lactic acid bacteria survive passage in the gastrointestinal tract and exert benefits there.
“Your gastrointestinal tract is one of the powerful immunological organs in your body. There’s a good deal of research out there now that suggests one can use lactic acid bacteria to stimulate that immunological response in a positive way,” he said.
His group is also working to develop the genetic tools through which lactic acid bacteria can be used as live delivery vehicles that can be ingested, pass through the stomach and then express and produce bioactive compounds, like vaccines and enzymes, in the gastrointestinal tract.
In 23 years at N.C. State, Klaenhammer has seen great changes as new genetic technologies have dramatically redirected the focus of his research. Early on, the work focused on “gene discovery missions,” searching for genes that were beneficial to the fermentation or probiotic roles of lactic acid bacteria. The advent of high-throughput DNA sequencing greatly expanded the view.
“Now, rather than fishing for and seeking specific genes, we can view the entire genome of the organism and related organisms,” he said. “We are coming to understand the genetic networks that are critical to the industrial performance of these beneficial bacteria. With this information, the potential benefits of the lactic acid bacteria are unlimited in the preservation of food, and human health.”
In addition to his own research program, Klaenhammer has served since 1993 as director of the Southeast Dairy Foods Research Center based in the College. The center, which attracts $1 million in research funding each year, is one of six in the country created to increase milk utilization via new information on dairy foods, ingredients and technologies.
Among its major research endeavors, the center is investigating the use of whey proteins as food ingredients, improvement in cheese flavor and, of course, delivery of probiotic lactic acid bacteria in dairy foods.
Though his work is important, Klaenhammer enjoys his time away from the university. He and his wife, Amy, and daughter, Ellen, spend time at a log cabin they built 11 years ago near Virginia, where they fish, boat and hike.
And professionally, because Klaenhammer’s work is focused 80 percent on research, he especially values his time with both graduate students and undergraduates. He co-teaches an undergraduate course in food microbiology and teaches a graduate course in food fermentation microbiology. He sees the classes as an opportunity to interact with students and generate new student interest in the field of food microbiology.
“If people like me can get in the classroom and talk with students about food microbiology or applied microbiology, they can get a view of the interface between the basic and applied and solving practical problems using biotechnology,” Klaenhammer said.
“When students are educated in the College of Agriculture and Life Sciences, they get a basic education at a very competitive university with a strong agricultural base. The trick for a graduate mentor is to frame the problem, provide the most cutting edge technologies and resources, then let them put their creativity to work. That sets the platform.”
Learning under Todd Klaenhammer “set the platform” for former doctoral student Cathy Donnelly, a professor of nutrition at the University of Vermont.
“To see Todd honored by the National Academy of Sciences gives me great pride,” she said. “His work ethic, his commitment to his students and to his institution are just outstanding. I can’t think of anyone who deserves it more.”