The challenge facing the Weizmann team was to capture, step-by-step, the complex process -- the whole of which takes place in a tiny fraction of a second -- that an enzyme molecule goes through as it performs its work. Their pioneering method was published in Nature Structural Biology. It was hailed as the first of its kind, and a potentially important tool for biophysicists.
To obtain the "live action" footage, Sagi and her team use a technique akin to stop-action photography, but on an infinitely smaller scale. They literally freeze the process at certain stages, using advanced methods of chemical analysis to determine the exact molecular layout at each stage. The most difficult part, says Sagi, was figuring out the correct time frames that would allow them to see each phase of enzyme activity clearly. She compares it to attempting to capture on film the swirling of syrup being mixed into cake batter one has to gauge at what points individual stages of the process will be most visible.
Building an animated sequence from individual frames, the scientists are granted a rare peek into the intricate dance of life on the molecular level. "This method," says Sagi, "represents more than a major breakthrough in the techniques used to understand enzyme activity. It changes the whole paradigm of drug formulation. Now we can precisely identify which parts of the molecule are the active regions (th
Contact: Alex Smith
American Committee for the Weizmann Institute of Science