Plant Protein Shape Decoded with 3-D Model: Genetically Modified Organisms on the Rise

Scientists have long wondered what sort of shape the basic building block of a plant takes. Now, they may have their answer. Researchers have provided the first three-dimensional model of an enzyme located within plant cells walls that links glucose into long-chain cellulose and that gives plants structure.

The findings, published in the Proceedings of the National Academy of Sciences, aren't just useful for studying plants in theory. Understanding the structure of the modeled plant enzyme, a cellulose synthase, could give researchers the tool they need to genetically engineer plants for better cotton fibers or stronger wood.

There is currently a huge push to create genetically modified plants.  Although controversy surrounds these organisms, they have greatly helped farmers in recent years. For example, about 75 percent of the Hawaiian papaya crop is genetically modified in order to withstand the papaya ringspot virus. When this disease first surfaced, it swept through fields and destroyed livelihoods. Yet with the introduction of this virus-resistant strain of crops, the Hawaiian papaya was able to survive.

In order to actually construct the model, the researchers examined the structure of one cellulose synthase found in cotton fibers. Cellulose synthase is an enzyme that catalyzes a chemical reaction. The scientists then compared that the model they created with the structure of a similar enzyme in bacteria. Surprisingly, they found that the proteins were similarly folded in key regions required for cellulose synthesis. They then examined mustard weed and identified potential causes for defective cellulose synthesis in mutant plants by making analogies to the modeled cotton cellulose synthase.

"Without the enzyme structure, you can't make strategically designed, rational projects about how to make beneficial changes to the proteins-but now you can," said Candace Haigler, a North Carlonia State crop scientist and co-author of the study, in a press release. "In the future, we could make cellulose easier to break down into biofuels while ensuring that the plants themselves are able to grow well."

The findings could be crucial for understanding how to modify plants in the future. In addition, the model could even be used to help create beneficial nanocrystals that have various properties and functions.