Good Intentions and Engineering Organisms that Kill Wheat.

• Author: Ingham, Elaine

A genetically engineered Klebsiella-planticola had devastating effects on wheat plants while in the same kind of units, same incubator, the parent bacteria did not result in the death of the wheat plants.

Consider that the parent species of bacteria grows in the root systems of every plant that has been assessed for Klebsiella's presence. The bacterium also grows on and decomposes plant litter material. It is a very common soil organism. It is a fairly aggressive soil organism that lives on exudates produced by the roots of every plant that grows in soil. This bacterium was chosen for those very reasons to be engineered: aggressive growth on plant residues.

Field burning of plant residues to prevent disease is a serious cause of air pollution throughout the US. In Oregon, people have been killed because the cloud from burning fields drifted across the highways and caused massive multi-car crashes. A different way was needed to get rid of crop residues. If we had an organism that could decompose the plant material and produce alcohol from it; then we'd have a win-win situation. A sellable product and get rid of plant residues without burning. We could add it to gasoline. We could cook with it. We could drink grass wine-although whether that would taste very good is anyone's guess. Regardless, there are many uses for alcohol.

So, genes were taken out of another bacterium, and put into Klebsiella-planticola in the right place to result in alcohol production. Once that was done, the plan was to rake the plant residue from the fields, gather it into containers, and allow it to be decomposed by Klebsielia-planticola. But, Klebsielia would produce alcohol, which it normally does not do. The alcohol production would be performed in a bucket in the barn. But what would you do with the sludge left at the bottom of the bucket once the plant material was decomposed? Think about a wine barrel or beer barrel after the wine or beer has been produced? There is a good thick layer of sludge left at the bottom. After Klebsiella-planticola has decomposed plant material, the sludge left at the bottom would be high in nitrogen and phosphorus and sulfur and magnesium and calcium-all of those materials that make a perfectly wonderful fertilizer. This material could be spread as a fertilizer then, and there wouldn't be a waste product in this system at all. A win-win-win situation.

But my colleagues and I asked the question: What is the effect of the sludge when put on fields? Would it contain live Klebsiella-planticola engineered to produce alcohol? Yes, it would. Once the sludge was spread it onto fields in the form of fertilizer, would the Klebsiella-planticola get into root systems? Would it have an effect on ecological balance; on the...