Malaria infects as many as 500 million people a year, and kills more than 1.5 million, mainly in Africa and Asia.
US researchers have created a yeast which can churn out large quantities of a related chemical, which can be easily converted into the drug. Writing in Nature, they say their work may eventually help slash the cost of artemisinin, which is currently to expensive to manufacture. It is currently extracted from a plant called Artemisia annua (commonly known as sweet wormwood), grown by farmers in Asia. But natural supplies are limited, and synthesizing the drug is very expensive.
A team from the University of California, Berkeley, succeeded two years ago in engineering bacteria to make a chemical precursor of artemisinin.
They have now gone one step further by developing a strain of yeast that can churn out large quantities of artemisinic acid - a chemical just one tiny change away from the drug itself. In theory, it should be now be possible to manufacture the drug much more cheaply.
The Berkeley team now hope eventually to drive down costs still further by using a similar process to stimulate bacteria to produce artemisinic acid. Bacteria grow much more quickly than yeast, and so could potentially offer a much more productive source of the chemical.
The researchers say it could still be several years before a microbe-produced version of artemisinin will be widely available.