NIH Record - National Institutes of Health

NIH Scientists Identify Nutrient that Helps Prevent Infection

Klebsiella pneumoniae interacting with a human neutrophil
Colorized scanning electron micrograph shows Klebsiella pneumoniae interacting with a human neutrophil.

Photo:  NIAID

Scientists studying the body’s natural defenses against bacterial infection have identified a nutrient—taurine—that helps the gut recall prior infections and kill invading bacteria, such as Klebsiella pneumoniae (Kpn). The finding, published in Cell by investigators from five NIH institutes, could aid efforts seeking alternatives to antibiotics.

Microbiota—the trillions of beneficial microbes living harmoniously inside our gut—provide some defense against bacterial infections. Scientists have been searching for natural treatments to replace antibiotics, which harm microbiota and become less effective as bacteria develop drug resistance.

The scientists observed that microbiota that had experienced prior infection and transferred to germ-free mice helped prevent infection with Kpn. They identified a class of bacteria—Deltaproteobacteria—involved in fighting these infections, and found taurine triggered Deltaproteobacteria activity.

Taurine, found naturally in bile acids in the gut, helps the body digest fats and oils. The scientists believe that low levels of taurine allow pathogens to colonize the gut, but high levels produce enough hydrogen sulfide—a poisonous gas byproduct of taurine—to prevent colonization. 

During the study, the researchers realized that a single mild infection can prepare the microbiota to resist subsequent infection, and that the liver and gallbladder—which synthesize and store bile acids containing taurine—can develop long-term infection protection.

The study, led by NIAID, was a collaboration with researchers from NIGMS, NCI, NIDDK and NHGRI.

The NIH Record

The NIH Record, founded in 1949, is the biweekly newsletter for employees of the National Institutes of Health.

Published 25 times each year, it comes out on payday Fridays.

Assistant Editor: Eric Bock (link sends e-mail)

Staff Writer: Amber Snyder (link sends e-mail)