Life

Cows’ methane burps may be fueled by a newfound organelle in gut microbes

The newly dubbed hydrogenobody is found in ciliates living in cows’ first stomach

Fluorescent microscope images of three ciliate protozoa from the rumen (first stomach) of cattle. The one on the left is egg-shaped and covered in waves of green, yellow and red hairlike cilia. In the center a clear, red goblet-shaped organism is topped by a bright orange shock of cilia. On the right is a green and yellow microbe that resembles an oval Koosh ball with a blue-green oval in the center. The center oval is the nucleus. These organisms have a newly discovered organelle that makes hydrogen and spurs other microbes to produce methane.

Single-celled microbes called ciliates make up about a quarter of the organisms that help cud-chewing animals break down plants. Scientists have now cataloged 65 ciliate species, including Isotricha prostoma (left), Entodinium caudatum (center) and Dasytricha ruminantium (right) shown here in 3-D fluorescent microscope images.

Chuanqi Jiang, Jinying He, and Che Hu/Institute of Hydrobiology/Chinese Academy of Sciences

By Tina Hesman Saey

A newly discovered organelle may hold the key to how much methane cattle burp out.