HOUSTON, April 30, 2007 Scientists from Baylor College of Medicine (BCM) and Rice University have discovered a new way to analyze the moving parts of large proteins a breakthrough that will make it easier for structural biologists to classify and scrutinize the active sites of proteins implicated in cancer and other diseases.

The breakthrough research will appear online this week and in an upcoming edition of the Proceedings of the National Academy of Science (PNAS). In involves a new mathematical algorithm that narrows down all the possible ways a protein might flex and bend. The math is used in conjunction with information captured via X-ray crystallography, a technique in which protein crystals are bombarded with X-rays, producing a diffraction pattern that reveals the precise three-dimensional arrangement of every atom in the protein.

"Increasingly, our discipline is faced with deciphering the structure of large, complex proteins in which some parts are constantly moving, even when the protein is locked in a crystal form," said lead researcher Jianpeng Ma, who holds joint appointments at both BCM and Rice. "We expect our method to be particularly useful in refining very large and flexible supramolecular complexes with limited diffraction data."

Nobel laureate William Lipscomb of Harvard University, one of the founding fathers of protein crystallography in the North America, said, "This recent success in X-ray crystallographic refinement is revolutionary for the field of structure biology in terms of improving large and flexible complex structures that are becoming far more abundant nowadays. It is one of the largest technical leap-forwards in X-ray refinement in the last two decades. It will fundamentally change the way people do structural refinement for large and flexible complexes."

Each protein is a chain of amino acids strung end-to-end, and Ma said current techniques are good at deciphering all but the most flex
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Contact: Jade Boyd
jadeboyd@rice.edu
713-348-6778
Rice University
30-Apr-2007