Navigation Links
MIT chemists engineer plants to produce new drugs
Date:11/3/2010

CAMBRIDGE, Mass. -- Humans have long taken advantage of the huge variety of medicinal compounds produced by plants. Now MIT chemists have found a new way to expand plants' pharmaceutical repertoire by genetically engineering them to produce unnatural variants of their usual products.

The researchers, led by Associate Professor Sarah O'Connor, have added bacterial genes to the periwinkle plant, enabling it to attach halogens such as chlorine or bromine to a class of compounds called alkaloids that the plant normally produces. Many alkaloids have pharmaceutical properties, and halogens, which are often added to antibiotics and other drugs, can make medicines more effective or last longer in the body.

The team's primary target, an alkaloid called vinblastine, is commonly used to treat cancers such as Hodgkin's lymphoma. O'Connor sees vinblastine and other drugs made by plants as scaffolds that she can modify in a variety of ways to enhance their effectiveness.

"We're trying to use plant biosynthetic mechanisms to easily make a whole range of different iterations of natural products," she said. "If you tweak the structure of natural products, very often you get different or improved biological and pharmacological activity."

O'Connor, graduate student Weerawat Runguphan and former postdoctoral associate Xudong Qu describe their engineered periwinkle plants in the Nov. 3 online edition of Nature. The research was funded by the National Institutes of Health and the American Cancer Society.

Engineering new genes into plants has been done before: In the 1990s, scientists developed corn that could produce an insecticide called Bt, which comes from a bacterial gene. However, O'Connor's approach, known as metabolic engineering, goes beyond simply adding a gene that codes for a novel protein. Metabolic engineers tinker with the series of reactions that the host organisms use to build new molecules, adding genes for new enzymes that reshape these natural synthetic pathways. This can lead to a huge variety of end products.

Most metabolic engineers use bacteria as their host organism, in part because their genes are easier to manipulate. O'Connor's work with plants makes her a rare exception. She doesn't believe one approach is better than the other, but one factor that drew her to engineer plants is that most plant synthetic pathways have not been completely revealed. "You can't reconstitute a whole plant pathway in bacteria unless you have all the genes," she said.

In previous experiments, O'Connor and her students induced periwinkle root cells to create novel compounds by feeding them slightly altered versions of their usual starting materials. In the new study, they engineered the cells to express genes that code for enzymes that attach chlorine or bromine to vinblastine precursors and other alkaloids.

The two new genes came from bacteria that naturally produce halogenated compounds. It's much more rare for plants to generate such compounds on their own, said O'Connor. It is also possible, though very difficult, to synthesize halogenated alkaloids in a laboratory.

To make alkaloids, plants first convert an amino acid called tryptophan into tryptamine. After that initial step, about a dozen more reactions are required, and the plants can produce hundreds of different final products. In the new genetically engineered plants, a bacterial enzyme called halogenase attaches a chlorine (or bromine) atom to tryptamine. That halogen stays on the molecule throughout the synthesis.

In future work, the researchers hope to engineer full periwinkle plants to produce the novel compounds. They are also working on improving the overall yield of the synthesis, which is about 15 fold lower than the plant's yield of naturally occurring alkaloids. One way to do that is to introduce the halogen further along in the process, said O'Connor.


'/>"/>

Contact: Jennifer Hirsch
jfhirsch@mit.edu
617-253-1682
Massachusetts Institute of Technology
Source:Eurekalert

Related medicine news :

1. VA names UCI orthopedic biomedical engineer a senior research career scientist
2. Ming Hsieh donates $50 million to establish a USC institute for research on engineering medicine for cancer
3. Researchers engineer microbes for low-cost production of anti-cancer drug, Taxol
4. Confectionery and chocolate engineering: Principles and applications
5. Engineering shorter wait times in the ER
6. Natural lung material is promising scaffold for engineering lung tissue using embryonic stem cells
7. Ellsworth Adhesives Announces New International Engineered Sales Representative
8. Surgeon-engineer team produce training software for robot-assisted surgery
9. Tissue engineers create a new way to assemble artificial tissues
10. UCLA engineer invents worlds smallest, lightest telemedicine microscope
11. University of Miami College of Engineering to develop new methods for data analysis
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/5/2016)... ... December 05, 2016 , ... The new knee compression sleeves ... to buy neoprene knee sleeves for lifting and any sport that requires ... on two main aspects to provide a higher quality knee sleeve performance. Firstly it ...
(Date:12/5/2016)... , ... December 05, 2016 , ... ... today that they have teamed up with The American College of Surgeons (ACS) ... ACS’s Committee on Trauma, the “Bleeding Control Basic” course is a pilot program ...
(Date:12/4/2016)... ... December 03, 2016 , ... ... and many more tools allowing FCPX editors to create professional looking video in ... , Perfect Harmony contains a beautifully designed 3D environment for placing in ...
(Date:12/4/2016)... ... December 04, 2016 , ... "Pro3rd Displace ... animation styles with unique displacement design elements," said Christina Austin - CEO of ... Choose from a variety of design styles that include both left aligned and ...
(Date:12/2/2016)... ... 2016 , ... Halfway through its partnership with First 5 LA, Western University ... than 15,900 children 5 years old and younger and treatment services to more than ... of five years to Western University of Health Sciences, UCLA and USC, beginning March ...
Breaking Medicine News(10 mins):
(Date:12/5/2016)... , December 5, 2016 PharmaBoardroom today releases ... . ... This report offers companies, investors, policymakers, and stakeholders crucial insight ... of Europe , home to some of the world,s ... pharmaceutical companies in Novartis and Roche, and with a number one ranking ...
(Date:12/5/2016)... VIENNA and TAIPEI, Taiwan , ... 12 months of treatment ropeginterferon alfa-2b showed non-inferiority to hydroxyurea ... demonstrated a significantly better safety and tolerability profile of ropeginterferon ... data from PROUD-PV and the ongoing long-term follow-up trial CONTINUATION-PV ... PharmaEssentia intends to present this data to the ...
(Date:12/4/2016)... ORLEANS , Dec. 2, 2016  Former Attorney General ... Jr., Esq. , a partner at the law firm of ... commenced an investigation into Lannett Company, Inc. (NYSE: ... Bloomberg published an article titled "U.S. Charges in Generic-Drug ... "antitrust investigation by the Justice Department, begun about two years ...
Breaking Medicine Technology: