University of Rochester

Professor Named Fellow of Microbiology Academy

November 4, 1999

A University of Rochester chemical engineer who is a leading expert on bone marrow culture technology has been elected a fellow of the American Academy of Microbiology, the leadership group within the American Society for Microbiology (ASM).

J.H. David Wu, an associate professor in the Department of Chemical Engineering and on the faculty of the Department of Microbiology and Immunology in the School of Medicine, focuses his research on blood cell formation in artificial bone marrow. His research team was one of the first in the world to design a three-dimensional tissue culture bioreactor that simulates bone marrow. The culture environment allows bone marrow cells to retain their shapes and remain within close physical contact with other cells, which is necessary for the crucial cell-to-cell communication. In comparison, the two-dimensional environment of the traditional culture dish flattens the cells and compromises cell-to-cell communication, giving scientists a skewed picture of how cells behave in the body.

Wu's bioreactor supports human blood cell formation for two months, enabling scientists to study the red blood cells, platelets, and white cells that differentiate from bone marrow stem cells. Scientists know that understanding how stem cells develop into blood cells will aid the treatment of hereditary and acquired blood disorders such as leukemia, hemophilia, sickle cell anemia, cancer, and AIDS. Industrial sectors have adapted Wu's concept, and the three-dimensional culture is now used by many university and industrial laboratories around the world in the search for better understanding of bone marrow biology and technology.

Another aspect of Wu's research focuses on studying the structure and function of enzymes, proteins with useful catalytic activity. He is currently studying a microbial cellulase complex that breaks down cellulose, long chains of glucose held together by hydrogen bonds. Cellulase enzymes are commonly used, for example, in household laundry detergents to remove lint and loosen dirt trapped in cotton fibers. These environmentally safe enzymes are used instead of corrosive acids for fading "stone-washed" jeans. Other enzymatic applications derive energy from alternative sources, such as producing fuel from dried corn stalks and leaves, and aid the de-inking process for paper recycling.

Wu is studying a bacterial protein of the cellulase complex that organizes and carries cellulase enzymes to attack cellulose. The bacterial protein uses an amino acid sequence similar to a human protein called calmodulin for assembling the cellulase molecules. Wu's team is the first to report that, despite the sequence similarity between the two proteins, the bacterial protein assumes a novel three-dimensional structure. With clearer understanding of how the enzyme works, Wu will be able to design better enzymes.

Combining biology and technology enables Wu to find direct applications of basic scientific research that will benefit others. Wu's desire to help others shaped the course of his education. After earning a bachelor of science in the areas of biochemistry and microbiology in 1976 from National Taiwan University, Wu moved to the United States to study biochemical engineering at Massachusetts Institute of Technology and earned his master's and doctoral degrees in 1982 and 1987, respectively. He joined the University of Rochester after completing his doctorate.

Wu is currently an editor for the Journal of Bioscience and Bioengineering and serves on the editorial board of Applied Microbiology and Biotechnology. He is also an editor of the second edition of ASM's Manual of Industrial Microbiology and Biotechnology, one of the best-selling books published by ASM. Wu has most recently served as the chair and advisor for the ASM's Division of Fermentation and Biotechnology, as well as a consultant to the Department of Energy, National Science Foundation, and National Institutes of Health.