‘Superhero’ microbiome bacteria protect against deadly symptoms during infection
In a paper published October 30, 2015 in Science, Ayres’ lab reported finding a strain of microbiome Escherichia coli bacteria in mice capable of improving the animals’ tolerance to infections of the lungs and intestines by preventing wasting—a potentially deadly loss of muscle tissue that occurs in serious infections. If a similarly protective strain is found in humans, it could offer a new avenue for countering muscle wasting, which afflicts patients suffering from sepsis and hospital acquired infections (many of which are now antibiotic resistant).
The Salk team identified a population of laboratory mice that appeared resistant to muscle wasting. By comparing the makeup of the intestinal microbiomes of these mice to mice that lacked resistance, the team identified a strain of E. coli that was present only in the wasting-resistant mice. When normal mice were given an oral treatment of this beneficial E. coli strain, they gained the ability to maintain their muscle and fat mass during intestinal infections and pneumonia.
Collaborating with the laboratory of Ronald Evans, the scientists discovered that during an infection by the pathological bacteria, the E. coli left the gut and moved into the fat tissues to induce protective responses that nourish the muscles. Normally, mice with lung and intestinal infections see a drop in a hormone known as insulin like growth factor 1 (IGF-1), a molecule that signals the body to retain muscle mass. But the protective E. coli activated the IGF-1 pathway in the fat tissues, preserving normal IGF-1 levels and maintaining the animal’s muscle in spite of the pathogenic infections. The team will investigate how long this E. coli strain can hold off the pathogens; whether the body’s immune system will eventually eradicate the harmful bacteria completely; and if such a microbe exists in humans.
Read News ReleaseFeatured Stories
- To inspire and educate: Salk’s Education Outreach is on a missionMotivated by Jonas Salk’s admonition to “be good ancestors,” Education Outreach strives to inspire the next generation of scientists. By running programs like the Mobile Science Lab or High School Science Day among others, Education Outreach encourages scientific literacy, enthusiasm in science as a career, and awareness of the value of basic research.
- Deepshika Ramanan–From iguana poop to breastmilkRamanan, a new assistant professor and microbiologist by training, made a chance discovery about animal gut bacteria that led to her fascination with breastmilk immunity.
- New strategic plan provides roadmap for enhancing diversity, equity, inclusion, and belonging at SalkGroundbreaking scientific discoveries require talented people behind the scenes, and the more diverse those people are, the more groundbreaking their discoveries. At Salk, improving diversity, equity, and inclusion is a commitment to both scientific discovery and humanity.
- Trinka Adamson–Supporting Salk science through animal careAdamson, senior director of Salk’s Animal Resources Department, works to provide the highest quality veterinary medical care, husbandry, enrichment, and professional technical support to enable our scientists to conduct their animal research and make their bold discoveries.
- Melissa Hernandez–Horses, hot sauce, and human brain researchHernandez, a postdoctoral researcher in the lab of Professor Rusty Gage, journeyed up and down the west coast and turned from scientist to hot sauce entrepreneur and back before finally settling at Salk to study neuroscience.