Biography of Todd

N early a century ago, Elie Metchnikoff of the Pasteur Institute in Paris proposed that lactic bacteria in fermented milk could promote the development of healthy intestinal microbiota. The consumption of probiotic lactic acid bacteria is useful in maintaining gastrointestinal health and has been used to preserve intestinal integrity and mobility and treat diarrheal diseases. Recent evidence from in vitro systems, animal models, and clinical studies suggests that lactic acid bacteria, primarily those from the Lactobacillus and Bifidobacterium species, can enhance both specific and nonspecific immune responses, possibly by activating macrophages, altering cytokines, increasing natural killer cell activity, and or increasing levels of immunoglobulins (1, 2). Recognition of in vivo and immunomodulatory roles for probiotic bacteria are now promoting opportunities for use of these microorganisms for delivery of biotherapeutics, such as vaccines, to targeted regions of the intestinal mucosa (3). Todd R. Klaenhammer, William Neal Reynolds Distinguished Professor of Food Science, Microbiology, and Genetics in the College of Agriculture and Life Sciences at North Carolina State University (Raleigh, NC), has devoted his career to studying lactic acid bacteria used in food bioprocessing. ‘‘I always found it inspiring to think that Louis Pasteur was a food microbiologist,’’ he says. In his Inaugural Article in this issue of PNAS (4), Klaenhammer and his group present the complete genome sequence of Lactobacillus acidophilus NCFM (North Carolina Food Microbiology). His team identified several genetic regions within the L. acidophilus genome that could contribute to the organism’s survival and interactions within the gastrointestinal tract.