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1 .This is Scientific American 60-Second Science. I'm Karen Hopkin. This'll just take a minute.
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2 .Yeast.They already participate in producing some of the most popular pain-killing substances around: beer and wine.
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3 .Now, scientists have engineered yeast that can also make one of the most powerful analgesics: morphine.
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4 .Their work is in the journal Nature Chemical Biology.
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5 .Opiates like morphine and codeine are essential for treating severe pain.
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6 .But making these meds isn't easy.
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7 .All are derived from opium poppies, and tens to hundreds of thousands of tons are needed to meet global needs.
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8 .The crops can also be affected by climate, disease and even political turmoil in the countries where the plants are grown, which further limits commercial production.
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9 .To get around these potential challenges, researchers have turned to yeast, an organism that can be grown easily on industrial scales.
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10 .The scientists inserted into yeast cells a handful of genes isolated from the opium poppy.
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11 .These genes encode the enzymes the plants use to produce opiates.
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12 .After tweaking the system to adjust the relative amounts of the enzymes, the researchers could feed their yeast a precursor chemical called thebaine, and get pure morphine in return.
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13 .The yeast can't yet make opiates from scratch.
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14 .But with a bit more effort and a few more enzymes, yeast may produce painkillers that are prescription strength.
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15 .Thanks for the minute, for Scientific American 60-Second Science. I'm Karen Hopkin.
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