Sweetener tagatose could support oral and gut health.

Engineers at Tufts reprogrammed bacteria using an enzyme from slime mold to produce tagatose with reported yields up to 95 percent, and the sugar is already designated by the U.S. Food and Drug Administration as generally recognized as safe.

Researchers at Tufts University report a new method to make the rare sugar tagatose using engineered bacteria and an enzyme discovered in slime mold. Tagatose tastes and behaves like table sugar but has fewer calories and browns during cooking. It is absorbed only partly in the small intestine and is largely fermented in the colon. The team said the biosynthetic route can reach much higher yields than conventional methods. Key facts: - Engineers used genetically modified Escherichia coli as microscopic production hosts and introduced a slime mold enzyme called galactose-1-phosphate-selective phosphatase (Gal1P). - The modified pathway converts abundant glucose into galactose and then into tagatose, with reported yields up to 95 percent compared with typical chemical methods that achieve about 40–77 percent. - Tagatose is about 92 percent as sweet as sucrose and contains roughly 60 percent fewer calories than table sugar. - The U.S. Food and Drug Administration has designated tagatose as "generally recognized as safe." - Because tagatose is only partially absorbed and is fermented by gut bacteria, it has a minimal reported effect on blood glucose and insulin levels, and emerging evidence indicates it may inhibit some cavity-causing oral bacteria and support beneficial microbes. Summary: The development could make tagatose more feasible for wider use because the biosynthetic method yields substantially more product than prior approaches and the compound is already GRAS. Researchers said scaling the process for industrial production will be the next step to determine whether broader adoption and the production of other rare sugars are feasible.