Plants are used in a variety of ways and have long been utilized for their medicinal properties and compounds. Specifically, through genetic modifications, plants can be altered so that their properties produce an even more desired outcome. According to researchers at the Massachusetts Institute of Technology, introducing bacterial genes to the periwinkle plant can lead to beneficial alternatives. But, how does this genetic mechanism work?

The periwinkle plant, also known as Catharanthus roseus, contains alkaloid compounds that enable it to be used in a multitude of pharmaceutical drugs. Associate Professor Sarah O’Connor and students observed this effect on the alkaloid, vinblastine. Vinblastine is an anticancer drug that is used to treat diseases like Hodgkin’s lymphoma. Using bacteria as the host organism enables engineers to easily adjust the plant’s genes. In particular, the inserted bacterial gene allows the plant to adhere halogens to the alkaloids resulting in a more favorable medicinal flora.

The engineered cells are able to express the induced bacterial genes. Specifically, these new genes code for enzymes that allow vinblastine to connect the halogens to it and other alkaloids found in the plant. The name of one of these enzymes, halogenase, binds chlorine and bromine to these alkaloid compounds. Since it is uncommon for plants to synthesize halogens on their own, it is necessary to introduce bacterial genes that code for the halogens into the plant. By synthetically altering the plant’s pathways, lead researcher O’Connor, was able to observe the new preferred outcome.

Scientists are continuing to identify important factors in the optimization of the periwinkle plant to produce a longer lasting drug. By genetically engineering the full plant and inserting the halogen enzyme later in the procedure, researchers aim to enhance their synthesis yield of the improved compound.

Discussion Question: While there are beneficial products of genetically altering plants, can you think of any negative effects that can arise? If so, what are they?

News Article: http://www.sciencedaily.com/releases/2010/11/101103141533.htm
Journal Article: http://www.nature.com/nature/journal/v468/n7322/full/nature09524.html