How bacteria create a piggy bank for the lean times: Basic science discovery could lead to improved biomaterial production

Now, by combining two cutting-edge techniques, cryo-electron microscopy (at McGill's Facility for Electron Microscopy Research) and X-ray crystallography, McGill researchers have, for the first time, been able to see the active enzyme in action.

"Until now scientists have been unable to understand the way bacterial cells store nitrogen in cyanophycin, simply because they couldn't see the enzyme in action," says Martin Schmeing, a Professor in McGill's Department of Biochemistry and the senior author on a recent paper on the subject in Nature Chemical Biology. "By stitching 3D images of the enzyme at work into a movie, we were able to see how three different structural units (or domains), came together to create cyanophycin synthetase. It's a surprising and very elegant example of a natural biomachine."

The next steps in the research involve looking at the other enzymes used in the complete biosynthesis and degradation cycle of cyanophycin. Once the researchers are able to see them in action, this would potentially give them a complete structural understanding of the processes involved and would allow them to figure out how to turbo-charge cells to make massive quantities of cyanophycin and related polymers for their green polymer biotech applications, such as in biodegradable water softeners and antiscalants or in the creation of heat-sensitive nanovesicles for use in targeted drug delivery.