Patricia Thomas in Harvard Magazine:
Having an office that physically spans these two worlds is metaphorically perfect for Schreiber, Loeb professor of chemical biology and one of several Harvard scientists who have been chipping at the wall between chemistry and biology to make way for an interdisciplinary enterprise called chemical biology. One of Schreiber’s many contributions has been in helping to develop technology now used by nearly all chemical biologists: robotic equipment that rapidly screens thousands of “small molecules” to see if they perturb a specific biological activity. Small molecules are chemical compounds with a molecular weight of 500 Daltons or less — about one-fiftieth to one-hundredth the size of most proteins. Yet when a small molecule latches onto a receptive protein, the protein’s shape is changed in a way that can make it more — or less — able to carry out its mission in the cell.