Studying the molecular mechanisms by which cells switch identity was a passion throughout Prof. Losick's career. He tackled this problem in a primitive organism, a bacterium that can either grow and divide or transform itself into a dormant cell known as a spore. Making a spore involves two cells, one that will become the spore and one that nurtures the developing spore. Prof. Losick and his colleagues discovered mechanisms by which a cell divides asymmetrically to give rise to the developing spore and the nurturing cell. They discovered an important class of regulatory proteins that controls the expression of large blocks of genes during spore formation and as we now know in many other kinds of bacteria as well. They elucidated exquisitely intricate mechanisms orchestrating the expression of hundreds of genes and ensuring that they are switched on at the right time and the right place. Dr. Losick and his colleagues also discovered that the protein products of those genes have distinctive subcellular addresses and localize in a choreographed movement, that the developing spore and the nurturing cell talk to each other in a chemical code that keeps events in one cell in register with events in the sister cell, and elucidated the molecular mechanisms by which these conversations takes place. Understanding bacteria is important to humanity because microbes are both beneficial and the causative agent of many diseases. The human body is a host to ten times more bacteria than human cells and bacteria are important agents of change in our environment and in Earth's history. Some microbes are pathogens whereas others are sources of medicines. Fundamental studies of bacteria inform efforts to combat infections and to harness the microbial world for the benefit of humanity.
Richard Losick is the Maria Moors Cabot Professor of Biology, a Harvard College Professor, and a Howard Hughes Medical Institute Professor in the Faculty of Arts & Sciences at Harvard University. He received his AB in Chemistry at Princeton University and his PhD in Biochemistry at the Massachusetts Institute of Technology. Upon completion of his graduate work, Professor Losick was named a Junior Fellow of the Harvard Society of Fellows when he began his studies on RNA polymerase and the regulation of gene transcription in bacteria. Professor Losick is a past Chairman of the Departments of Cellular and Developmental Biology and Molecular and Cellular Biology at Harvard University. He received the Camille and Henry Dreyfuss Teacher-Scholar Award, and he is a member of the National Academy of Sciences, a Fellow of the American Academy of Arts and Sciences, a Member of the American Philosophical Society, a Fellow of the American Association for the Advancement of Science, a Fellow of the American Academy of Microbiology, and a former Visiting Scholar of the Phi Beta Kappa Society. He is 2007 recipient of the Selman A. Waksman Award of the National Academy of Sciences.