Davis Appointed At Med School

Dr. Bernard D. Davis, head of the department of bacteriology and immunology at the Medical School since 1957, has been named the first Adale Lehman Professor in medicine. Dr. Davis is a microbial geneticist who investigates bacterial cells to study heredity and control mechanisms in all living organisms.

A summa cum laude graduate in 1940 from the Medical School; Dr. Davis had been professor and chairman of the department of pharmacology at the New York University College of Medicine prior to joining Harvard.

His particular interest is the mechanism called "repression"--a chemical feedback phenomenon that illustrates "intelligence" in cellular behavior. Cells that for some reason have changed or mutated--as in cancer--continue to produce materials they do not require. In normal cells an enzymatic feed-back or braking system slows or stops the production of these no-longer-needed materials.

Knowledge of this chemical feed-back mechanism may point to a new and extremely important type of genetic control of biological systems--the regulation of the synthesis of enzymes. The control apparatus can be compared to the operation of an automated factory in which the product-output is regulated in accordance with supply and demand.

More recently Dr. Davis has studied problems of cell-membrane permeability--the transport of materials in and out of the cell.

He has shown that the unit responsible for the transport of citric acid--essential for the combustion of fuels in all cells--across a cell membrane, can be altered by repression as well as by mutation. This discovery offers a powerful tool for approaching one of the least-understood aspects of cellular physiology--the remarkable capacity of cell membranes to select only certain substances for passage in and out of the cell.

Berry described the mechanism that acts in the cell membrane to permit the passage of substance as one of the major mysteries of cell physiology.

Dr. Davis, a native of Franklin, graduated magna cum laude from Harvard in 1936.