A California research team has mapped an entire group of human enzymes, providing important information for the development of a new generation of drugs to treat cancer and other diseases. The findings will be published in the Dec. 6 issue of Science. In the study, the team from the Salk Institute for Biological Studies and the biotechnology company SUGEN created a detailed catalog of the 518 protein kinase genes encoded by the human genome. Protein kinases are among the most important regulators of cell behavior. By chemically adding phosphate groups to other proteins, they control the activity of up to 30 percent of all cellular proteins, and are involved in almost all cellular functions.