Engineered yeast helps bees during pollen shortages

Honeybees face pollen shortages, and researchers engineered a yeast to produce pollen sterols to support brood production in pollen-scarce conditions.

Engineered yeast provides rare but essential pollen sterols for honeybees

Scientists used a yeast strain, Yarrowia lipolytica, to produce sterols typically found in pollen and integrated this biosynthetic pathway into a platform strain. The sterol-rich yeast was then added to a meridic diet for honeybee colonies in controlled trials. Colonies that received the sterol-enriched diet reared brood longer than those on diets lacking suitable sterols, suggesting the approach could compensate for pollen gaps during flowering dearth periods. The study also compared multiple yeast backgrounds, including a mixed-sterol strain ST12178 and a baseline platform strain, and examined production at different scales from small cultures to bioreactor fermentations. A pollen-starvation trial in a glasshouse setting tested whether sterol-supplemented diets could sustain brood when natural pollen was removed.

To address safety, the yeast biomass was heat-inactivated before use in the diet. Sterol content was quantified by gas chromatography–mass spectrometry in yeast, diets, and bee tissues, and the team conducted analyses on brood counts, hive weight, and patty consumption across several feeding trials. The work also included a real-world pollen-starvation experiment to gauge colony resilience under floral scarcity. While the results are promising, the authors emphasize the need for broader testing and careful oversight before any field deployment.

The paper reflects a trend toward nutrition engineering in pollinator health, using microbes to supplement what flowers cannot always provide. If validated at scale, sterol-enriched diets could lessen pollen competition among bee species and offer a buffer against climate-driven pollen gaps. Yet introducing engineered microbes into beekeeping raises biosafety, regulatory, and ecological questions that demand independent replication, transparent risk assessment, and clear labeling. The research design is robust—combining lab work, fermentation, and semi-field trials—but real-world adoption will depend on long-term studies and governance that balance innovation with safeguards.

Highlights

Ongoing field tests will determine if this microbial nutrition approach can reach practical use in beekeeping.