Scientists have discovered an enzyme used in nature to make powerful chemicals from catnip to a cancer drug, vinblastine. The discovery opens up the prospect of producing these chemicals cheaply and efficiently.
They are produced naturally by some plants such as the medicinal Madagascar periwinkle, but faster-growing plants could be used to produce them. With synthetic biology, improvements could also be made to them.
The study, to be published in Nature on Thursday, was led by scientists from the John Innes Centre, an institute on Norwich Research Park strategically funded by BBSRC.
"Thousands of chemicals are derived from the enzyme we have called iridoid synthase," says senior author Dr Sarah O'Connor from the JIC and the University of East Anglia.
"We can start to use it to come up with new-to-nature structures with biological activity of benefit to both medicine and agriculture."
Many aphids, often important agricultural pests, produce sex pheromone chemicals that are identical to or that closely resemble the iridoid synthase product. Strategic use of these iridoid chemicals could be used to disrupt the aphids' breeding cycle or to repel them from crops.
The anticancer ingredient vinblastine sulphate is currently derived from the Madagascar periwinkle plant. The iridoid synthase is an essential step in the production of this compound. But vinblastine is produced in just very low levels and the drug has many side effects. The hope is to find a way to produce it more cheaply, easily and with a chemical structure that lessens side effects.
"We need to identify more enzymes to see the entire pathway used in nature to make this potent compound," said Dr O'Connor.
"But the enzyme we have discovered is also the basic scaffold for many other iridoid chemicals and we can start to experiment with building new chemical structures with biological activity."
The backbone of all iridoids consists of two fused rings and scientists have been trying to track down what makes this ring system. Experiments showed that iridoid synthase is the enzyme responsible.
Scientists already knew the enzyme preceeding iridoid synthase and how the gene encoding it is expressed. The lead author, Dr Fernando Geu-Flores from JIC, therefore looked for enzymes that are encoded by genes expressed in a similar way and narrowed down their search to 20 enzymes.
Research published in the 1980s indicated that the missing enzyme is dependent on a particular compound called NADPH, which narrowed the search down to two enzymes.
O'Connor and her co-workers will also investigate whether the enzyme is important in a simple chemical reaction used by chemists for nearly 100 years. Scientists are trying to identify which enzymes catalyse a reaction called the Diels-Alder reaction, named after the Nobel prize-winning scientists who discovered it. A better understanding of how the iridoid synthase works could open up new ways to make pharmaceutical compounds using synthetic biology.
Norwich BioScience Institutes: http://www.nbi.bbsrc.ac.uk
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
A sophisticated prediction software ran tens of thousands of scenarios and picked one team to win 60 percent of the time
The Insurance Institute For Highway Safety tested more than three dozen late-model vehicles to see if new safety features are preventing deaths. Chip Reid reports on the results.
Physicist Charles Townes died Tuesday. He was a key inventor of the laser and won the Nobel Prize for his discovery in 1964. But his career didn't end there.
In order to learn how lava travels before spurting out in an eruption, researchers designed a small rolling robot that can go deep inside a volcano and send live images to the surface.
It may not sound like the most useful of scientific endeavours, but the methods used to turn a hard-boiled egg back into its liquid state could bring major benefits to areas as diverse as cheese-making and cancer research
The science behind how water releases the funk from all the yeasts and bacteria hiding in your dog's fur.
The oldest rocky planets yet are 11.2 billion years old, just a little younger than the universe - meaning the galaxy made an early start on planet building
It's usually only possible to see the spot where a laser lands rather than its path, but now an ultrafast camera has caught those photons mid-flight
A team of Indian physicists has made a mathematical model that purports to explain why ants don't have traffic jams. NPR's Joe Palca explains as part of his series, Joe's Big Idea.
On a fall morning in 2009, a team of three young physicists huddled around a computer screen in a small office overlooking Broadway in New York. They were dressed for success—even the graduate student’s shirt had buttons—and a bottle of champagne was at the ready.